Ok, I know this subject has a number of threads. But What I have found has raised more questions, without answers.

What I have:
86’ SE 2.8 V6
Auto Trans.

The problem I am trying to correct:
The car has 150,000 + miles on it, but has been very well kept. A few weeks ago my oil pressure took a dive when warm at idle. I check it with a mechanical gauge, hoping it was just the sending unit (not). When warm at idle I get about 10 to 15 psi. When cold or above about 900 to 1000 rpm everything is normal.

In reading a lot of threads, it looks like I may have spun a rod bearing and or it could be my oil pump. So I got a new high flow oil pump, new rod bearings, pan gasket and main bearing (more on this later). Also, I know it’s time to replace all trans and engine mounts. So I got those as well.

Now reading threads here, it does not look like I need to pull the engine to do all of this work.

Questions:
1. The of the threads tell how to remove the pan, but you have to rest the engine on a 2x4 with the front pulley. If I do that how do I turn the crank to get to all of the rod bearings?
2. One of the threads tells how to replace the mains by just backing off the main bolt, but not removing them. But the crank will have a lot of weight from the trans on it. How do you get the bottom half of the bearing out & the new ones in?
3. Would it be better to do the bearings, oil pump & pan gasket before I replace the trans & motor mounts? That way the engine may move around a little more when removing the pan.

I am trying to get this done over the Christmas shutdown where I work. (It’s my daily driver!)

Thanks for your help.
Chuck

In the meantime, change the oil for a heavier weight. That should keep the pressure higher when warm.

quote Originally posted by ChuckRock: Questions: 1. The of the threads tell how to remove the pan, but you have to rest the engine on a 2x4 with the front pulley. If I do that how do I turn the crank to get to all of the rod bearings?

After the pan is removed, raise the engine and the block. Allow the engine to rest on the mount.

quote Originally posted by ChuckRock: 2. One of the threads tells how to replace the mains by just backing off the main bolt, but not removing them. But the crank will have a lot of weight from the trans on it. How do you get the bottom half of the bearing out & the new ones in?

Loosen all the main cap bolts a couple of full turns. Replace main bearings one at a time but be sure to get each cap fully seated and snug (finger tight) before rotaing to do the next one. Use a good quality assembly lube or STP on the bearing surface.

quote Originally posted by ChuckRock: 3. Would it be better to do the bearings, oil pump & pan gasket before I replace the trans & motor mounts? That way the engine may move around a little more when removing the pan. I am trying to get this done over the Christmas shutdown where I work. (It’s my daily driver!) Thanks for your help. Chuck

I would replace the rubber mounts after I did the other work.
Make sure to use some plasti gauge or measure the crank prior to final assembly.
Rember to be sure to have the proper clearance for the pickup screen from the bottom of thee pan and that the tube is seated good in the oil pump as well. Refill crank case with 5w30.
Have fun!

[This message has been edited by Indiana_resto_guy (edited 12-12-2006).]

quote Originally posted by Indiana_resto_guy: ....

what he said

If you spun a bearing you will be wasting your time replacing the bearings in most cases. Usually if a bearing spins it will chew up the crankshaft and wear it down a bit causing excessive clearance issues and when you start it with the fresh bearings you might spin the bearings again.

If it's not knocking, I would say it's excessive clearance in either the main bearings or the cam bearings and not a spun bearing. Just my observations from previous engines I have had to rebuild.

I second what fieroluv said. So its just low pressure when hot at idle? Not low pressure when hot at cruise? Is it knocking loudly?

Replacing the rod bearings is fairly stop-gap, all the wear in the cam bearings is likely what's contributing to the low pressure. Thicker oil may make it worse. Why? Because the oil pressure guage reads the pressure as it pushes against the oil passages, not the pressure at the other end of the oil passages where the bearings are. Thicker oil is harder to push through the oil passages so the guage reads higher pressure when in fact the pressure at the bearings may very well be lower, expecially when cold and the oil is thick. When the engine is cold you'll experience less initial oil flow, translating into a greater risk of even faster bearing wear.

Like he said, after pulling off the pan you put the mount back on and the wood under the mount, then you can rotate the crank.

You should do a visual inspection of the rod journals for any kind of scoring, if you see some but the bearing's not spun then you can use 400 emory cloth strips to polish out the scoring before installing the new bearing. Be sure to clean off all sanding debris if you do this.

James

Be absolutely sure that you have the pick up tube fastened securely to the oil pump. I'm passing along that little tip from experience, mine fell off, had to pull the pan again, machanic at work gave it a little tak weld for me, fine now except for the embarrasment at the time.

I replaced rod bearings about 5 years ago, it's been fine ever since. I caught it early, just started making noise while hot at above idle at the end of an oil change cycle.

it really is just time to have the engine rebuilt. Even after replacing the bearings, you still have the worn rings and cylinder walls, possibly a damaged crank, etc. You could have the crank and block taken to a machine shop and checked out, bored out/ground down to the next size if neccessary, maybe have the heads rebuilt at the same time. I know the pain you're going through, I spun a rod bearing on my duke, just happened without warning. The car has been 100X more reliable and running better since I had the rebuilt engine put in. I would have loved to have done it myself if I'd had the tools, time, etc.

------------------

1984 Fiero SE

I don't understand you purchasing new rod and main bearings not knowing what size you need. What I mean is you surely will put the standard size back in. You need to plastic gauge the bearings and see what the clearance is. For example if the clearance was 10 thousand then you surely would not want to put a standard size back in. this bearing clearance is very important. If it were me and it had 10 to 15 pounds pressure on idle when warm then I would switch to a heavier weight oil. 10W/40 is a good starting point. The oil light should not come on with 15 pounds pressure. Just my thoughts I just don't like to see good money thrown after bad. With 150,000 miles it needs a complete overhaul.
Don

Wow! That was some fast responces! Thanks, to all!

I may not have a spun bearing (please,please,please,...).

I other cars I've worked when a bear has spun with would start making lots of noise and then motor no more workie!

The engine sounds strong and no other sounds than a puring engine even when I put my foot in to it (alot!). So, I am hoping it's just the oil pump on it's way out. Like I said it's been very well maintained. Fresh oil & filter, ever 3 to 4k. I have not and don't like to use heavier oil for the reason JazzMan said. I had a 81' Ford Ranger that had a bad know, most likely rod bearing. I tried thicker oil and it ran ok for about a year. Then loader noise and motor no more workie! Hey it was a $100 truck!

Back to my question on replacing the mains. Isn't there not a lot of weight on the mains with the torque converter mounted to the flywheel or is most of that weight being supported by the trans?

Also, doesn't the oil pickup bolt to the oil pump?

And thanks again for the help!
Chuck

On the pump pickup, no, it just presses into the pump housing. A tack weld ensures it stays there too!

quote Originally posted by JazzMan: Replacing the rod bearings is fairly stop-gap, all the wear in the cam bearings is likely what's contributing to the low pressure. Thicker oil may make it worse. Why? Because the oil pressure guage reads the pressure as it pushes against the oil passages, not the pressure at the other end of the oil passages where the bearings are. Thicker oil is harder to push through the oil passages so the guage reads higher pressure when in fact the pressure at the bearings may very well be lower, expecially when cold and the oil is thick. When the engine is cold you'll experience less initial oil flow, translating into a greater risk of even faster bearing wear.

My point was that older engines can benefit from higher weight oil because their clearances are greater than when they were new. If the pressure is higher at where its read, its going to lose just as much pressure as a lighter weight oil, thus a net increase of pressure.

If you had a spun bearing, you would know it, trust me.

When you say the oil pressure is low, how low? Minimum specs from GM are very forgiving, something like 15psi at 2000 RPM, though I think it might be even lower than that. Is the oil light on? I drove one with the oil light flickering on at idle for a LONG time. It did finaly die, but my younger brother was driving it at the time, so I doubt it was so much about the oil pressure....

You can take the oil pan off, then put the front mount back on to support the engine so you can turn the crank.

There is a certain amount of force on the crank at all times, Ive never bothered trying to figure out exactly what offsets what, but as long as you only remove one main at a time you will be fine.

You may encounter some trouble getting the mains to "roll" out of the block. I had a couple stuck tight. I took an old main and cut it in half, chamfering the edges, then put it against the crank and drove the original bearing out with it.

As far as clearances, you do not need about oversized bearings, if the crank has worn enough to fit a .010" oversized bearing, you have much bigger problems. You could plastiguage it, but its just going to depress you if you do find anything, its not like every journal is going to be exactly .011 over and even across the bearing. If you were doing a rebuild and long haul, plasiguage is an absolute neccesity, but in this case, being you wont have the engine out, its just going to be something to bum you out and make you paranoid (or reassure you if its good) at any rate, unless you are ready to pull the engine and replace the crank, its not going to help.

You will likely find some scratches and scoring on the crank. Rule of thumb (or finger :P ) is that if you can run your fingernail over it and not catch, its ok. Not that you could do anything if this was the case anyway. Your only option is to smooth out any realy bad scores with some sandpaper. You will want to take 1000 grit, cut it into long strips and oil it. Then pulling it over the crank as to cover 180* of crank, count the number of swipes you take, then reverse sides and do the exact same number of swipes. The actual effectiveness of this can be debated, but it makes me feel better to know I tried, lol.

Make sure you keep the rod caps pointing the right direction as well, and make sure the rod caps get put back on the rod they came off of. Dont forget assembly lube.

[This message has been edited by 86GT3.4DOHC (edited 12-12-2006).]

As a couple of people have mentioned, it's highly unlikely that it's actually a ROD bearing, and actually a crank MAIN bearing. Those typically are what go out first on a Fiero. If a ROD bearing goes out, the engine is very unforgiving and you usually don't have much time. I have an engine I pulled out of a 5-Speed Fiero where one of the entire pistons and connecting rods basically desintegrated into a bunch of ity bity pieces that I hear strewn all over the inside of the oil pan.

The ONLY way you can really do this right, is if you remove the engine. Lucky for you, the Fiero V6 is actually really easy to remove when you have an automatic transmission. All you need to do is disconnect everything from the motor, remove the starter, get under the car, and remove the bolts that attach the flywheel to the torque converter. Once everything is disconnected, you CAN EASILY remove the engine from the top with the cyl heads and intake manifold still bolted on. Once it's on the engine hoist, you can drop the pan, and get to work on it.

This CAN be done on the cheap, but simply replacing the main bearings doesn't always work, and you're usually back in the same situation after a couple of weeks. You don't have to remove the pistons, but you will have to remove all the main caps. You should have just enough clearance (by pulling the crank down) that you can slip the main bearing caps off the block, and put new ones in. MAKE SURE you clean the crank journals VERY well with some alcohol, wipe them with a soft rag. You'll then want to put assembly lube ALL over the main bearings and the crank journals.

Your big problem is that some wear may have been taken on the crank journals. Hopefully, it's just the bearing that's taken all the beating.

I'd like to see a motor where ALL of the bearings are roller bearings. How cool would that be?

10,000 rpms in a street motor!

------------------
Todd,
2006 Pontiac Solstice
2004 Volkswagen Beetle Convertible (Wife's Car)
2002 Ford Crown Victoria LX
1987 Pontiac Fiero SE / V6 (3.2) 5-Speed
1984 Pontiac Fiero 2m4 SE
1984 Porsche 944 5-Speed
1981 Pontiac TransAm (Olds 455BB)
1973 Volkswagen Type-2 Transporter

ok, let me put on my "House" persona and correct a few glaring misconceptionse stated here about bearings and what you can and cannot do. I know some of the previous posters may not like it, but truth hurts, and here we go:

1. bearings are marked with their sizes. if you pull them off and plasti-guage them, you won;t find .010 under or any other convenient off the shelf size. if they are marked .010, .020 etc, the crank has already been refinished. You cannot plastiguage the old bearings, you must put in stock (or stamped sized) bearings to test them. if it exceeds the book specs, you will need to have the crank redone, or slap the same size in up the oil weight and HOPE it lasts til you are ready for your rebuild/replace.

2. If they appear scored, you are screwed. polishing them twith crocus clothe? gimme a break. any visible scoring is deep enough for a minimum .020 grind. you are not going to "polish" that out with crocus cloth. you will never get them perfectly round.
there is a reason there are machine shops for this stuff. it is a precision fit. don;t fool yourself or waste your time. your best bet is replace the bearing, up the oil weight, shim the regulator valve on the oil pump to increas your pressure and start planning your rebuild/replace in short order. or have the crank refinished, and do it right.

the sudden change in oil pressure in your case , with no obvious noise can be the result of the oil pump regulator sticking.
a spun bearing crank/rod will make noise. sudden changes in pressure with no noise usually indicate some type of oil system issue. clogged pickup screen, reg failure, seal failure.
if you do trace it to a bearing issue, it can also be cam bearings, wear there are more impacting to oil pressure that crank/rod bearing failure, and there is less noise indication. they are the first stop on the oil path.

now on the issue of oil wieght and pressures. replacing the stock 5w30 with ridiculously high wieght oil is not the proper response either. you need the cold temp flow, and high temp resiliency. simple multi viscosity change of one step is not going to
cause a major issue. going to 10w30 or 15w30 are minimal increases that may help the issue without needless and fruitless stop-gap mechanical work.

in short, you could try a hi volume oil pump, and fresh bearings on the lower half, all relatively easy short term fixes if you are intent on working on your back for a few days. you may get another year out of it, or just a day or a week, especially if you find scored bearings or ones worn into the copper. that is the nature of trying to work around the correct fix. I learned long ago, there are no cheap fixes, only the right fix or wasitng time and money.

Being 18 and cheap, ive replaced bearings on 2 motors to fix knock issues and a low pressure issue on a different motor. 1st time didnt work, I was even so cheap to just replace the one rod that I thought was bad, it did get rid of some of the noise, i should of replaced more than just that one. Second motor, a 87 3.8, was starved of oil on its first start-up. It had low oil pressure because wear on the main bearings, right down to the brass. I replaced ALL of them and made it much more quiet at idle but right around 2,000rpm driving it was louder than hell, sounded like a diesel. I drove it no probs at all for 2,000 miles like this. I took the motor out to do a ecotec swap, otherwise id still be driving it.

quote Originally posted by tjm4fun: ok, let me put on my "House" persona and correct a few glaring misconceptionse stated here about bearings and what you can and cannot do. I know some of the previous posters may not like it, but truth hurts, and here we go:

Just to add to what you've said...

As far as CRANK main bearings go, for whatever reason, all the motors I've seen that have had them go bad, it's usually the upper bearing cap that has failed (the bearing on the block itself, not the main cap). I don't know why that is, you'd think it would be the bottoms???

Maybe it's just a co-incidence, but I thought I'd mention it.

You CAN actually have a main bearing cap go bad, slowly... (typically from a period of overheating). It MAY drive totally normal with no loss of power under normal driving conditions. But over time (usually a matter of a week or two), the engine will begin to make noise at it's higher rpms. This will gradually go further and further down in the rpm range until it's doing it at idle.

With a ROD bearing, you hear it at ALL rpms...

------------------
Todd,
2006 Pontiac Solstice
2004 Volkswagen Beetle Convertible (Wife's Car)
2002 Ford Crown Victoria LX
1987 Pontiac Fiero SE / V6 (3.2) 5-Speed
1984 Pontiac Fiero 2m4 SE
1984 Porsche 944 5-Speed
1981 Pontiac TransAm (Olds 455BB)
1973 Volkswagen Type-2 Transporter

quote Originally posted by tjm4fun: 2. If they appear scored, you are screwed. polishing them twith crocus clothe? gimme a break. any visible scoring is deep enough for a minimum .020 grind. you are not going to "polish" that out with crocus cloth. you will never get them perfectly round.

You would be suprised how small a mark you can see You can see the distortion on the bottom of a burnt CD, and that is nothing more than microscopic pockets in the material, far less than .010. The idea behind polishing a crank is not to perfectly resurface it, its to take off the extreme high ridges in a damanged crank, or just remove very light scoring in a good crank. Most all machine shops that turn cranks (though almost none really do, they all send them out to be done) also polish the less damaged ones. By using a very light abrasive, with careful usage, you can refinish the surface. You're not going to resize a journal to .010 under with sand paper, but you can clean up the worst of a damaged journal. The worse the damage, the more material is going to have to come off the bearing before it seats, and thats just more material thats going to be in there. To do it properly you need to have a set of micrometers to measure the crank when done, though you shouldnt me taking off enough to be measured.

As far as this guy is concerned, if you're just trying to keep an engine running for a little while longer, rolling in new bearings is an acceptable option. It should only take a couple of hours, I think like 2.5 last time I did it, and alldata calls for less than that. It is good to mention that you will want to check the back of the original bearings for markings, most likely you will find a 4 digit code representing the date of manufacture back in the 80's, but if you do find a 3 digit 0X0 oversize stamping, you will have to replace the bearings with the same oversize.

I think the main concern in this issue, is determining if the oil pressure actualy is low enough to warrant concern, or he is just being paranoid (which we all do). If you're not triping the oil light, you're fine. Even if you are, its not neccesarialy too low, like I said the GM specs are very forgiving. I sure would not go tearing into the engine if its not below minimum specs. There is a chance of catastrophic failure here, and a good chance that the new bearings will not last as long as the current ones would, then again if you are careful it might last another 150,000 miles.

most of the above concerns are all valid. there may be a spun bearing. there may be bad cam bearings.
but, for as little work as swapping in new rod & main bearings - go ahead and do it. all other choices involve motor removal. I've had rod bearing wear down, yet not spin. it did wreck my oil pressure. I did polish that journal & replace the bearing. it was fine. worked great. lasted.

also - for the guy talking about oversize bearings - this only happens when you get the crank machined for oversized. this size change is NOT caused by wear - and if it is - theres something VERY wrong. and, if the crank was machined previously for oversized - it is marked.

plastigaging lets you select bearings for a more close match among a group of same size bearings. while everybearing "should" be exactly the same - they are not. if you are doing 6 rod bearings - buy 10. they are cheap, and this way you can match them up.

Hmmm, now it’s sounding more and more that it may not be a spun bearing. I am still going to replace the oil pump.

But should I pull any of the bearing out to check for scoring?

If there is not should I just put the old ones back?

Or at that point is just better to replace them with the new ones, even if I don’t find anything wrong?

I think I can return the new bearings I just got.

Thanks again,
Chuck

I would only do that on a car I was intending to sell soon. The whole bottom end (block) should be done to do it right for a reliable keeper. Then with a new bottom, its not a good idea to put the heads back on without rebuilding them too. For the work involved, its not much more in labor and expense to do the whole job right in the first place. For example, lots easier to tear down the crank assembly out laying on the floor or a bench than crawling around underneath with 2x4s and prybars.

quote Originally posted by ChuckRock: Hmmm, now it’s sounding more and more that it may not be a spun bearing. I am still going to replace the oil pump. But should I pull any of the bearing out to check for scoring? If there is not should I just put the old ones back? Or at that point is just better to replace them with the new ones, even if I don’t find anything wrong? I think I can return the new bearings I just got. Thanks again, Chuck

yes, drop the pan and look. you will know which bearing(s) it is really quick - they will be the "loose" rods, which have wiggle to them. and, replace them all anyways - they are cheap, and it dont take long. the main bearings cost a little more.

quote Originally posted by ChuckRock: Hmmm, now it’s sounding more and more that it may not be a spun bearing.

Don't even waste your time with just installing a new pump as you will still have low pressure caused from normal wear in the rest of the engine.
You can pull caps if you want but one or two won't cut the mustard they all need to be inspected. So as long as the caps are off already install new bearings it is not much trouble to do so. I have done several higher mileage engines (in my own cars) with this treatment and oil pressure went from 6-7 lbs. @ idle (flashing gauge) @ normal operating temprature (lowest acceptable according to GM) to 20 + under the same conditions. Two I still have are running strong at 3 plus years and normal maintainance. I run them moderate to heavy accelleration and no problems. It is very important to measure the crankshaft to make sure it is within specs.
Digital calipers are cheap enough and well worth a few bucks. Just make sure that when you measure to measure the whole thing, both sides and the middle, watch for the oil hole that will mess you up big time.
When installing the new pump do not forget to prime it properly. I use STP oil treatment to fill the pump with and a vasiline plug so it will not make a mess.

If you have ANY scoring, (if it were me) replace the crankshaft as it will have a good chance of being out of round. A remaned crankshaft will come with new bearings. Quite a bit more work, but doable in an automatic tranny car.

quote Originally posted by AP2k: My point was that older engines can benefit from higher weight oil because their clearances are greater than when they were new. If the pressure is higher at where its read, its going to lose just as much pressure as a lighter weight oil, thus a net increase of pressure.

That does't apply to our motors because on our blocks the oil passages to the crank bearings comes off of the cam bearing saddle, so any wear at the cam bearings reduces flow directly to the mains and rods. The sum of the oil flow stays the same, more just goes out the cam bearings and less to the bottom end. The newer 3.4 and other motors have a dedicated passage for the bottom end instead of siphoning it from the cam bearings.

James

Chuck,

I think you need a paradigm shift.

Don't half ass rebuild the engine. For the cost of what you're considering, you can find a decent second hand motor at one of the many excellent wrecking yards in the Vanc./Portland area. Probably somewhere between 3 and 5 hundred bucks, the better yards do an oil pressure check and compression test on their engines, and will provide some sort of guarantee. Look for a Chevy 2.8/173 cu. in. motor of about the same vintage as yours. If it doesn't have a distributor, look for a metal plate where the distributor should be--it should be adaptable. Or even a 3.1 will work.

If you want to come down to Reno and help me pull an engine, I have a good running 2.8 (long block with everything but the plenum) that you can have for the price of a good meal in one of the casinos (well a really good meal!) It needs some seals, but is otherwise a good engine.

[This message has been edited by Brian Lamberts (edited 12-13-2006).]

Brain, I know it’s not the best way to go about it. But, like I said I plan on doing a 4.9 swap in a year or so. So I just want it to get to and from work until then. I’ve already have a high volume oil pump & pick-up tube from The Fiero Store. I’ll most likely go ahead replace at least the rod bearings. The idea I have is to just keep this going for while I build a Caddy 4.9, which a co-work is going to give to me. It has 80k on it and he got hit in the rear. But, I want to do it that right and dress it up nice. I don’t want to have to hurry up and get it done so I can drive to work. I’ll have to pass driving down to Reno, sorry! Thanks for the offer

When I get the current engine out, I am hoping it not total shot. I was thinking about rebuilding it and selling it.

quote Originally posted by Brian Lamberts: Probably somewhere between 3 and 5 hundred bucks,

What he's talking about will cost about $30. Unless he does the pump too, then $30 more.

You still havent answered any of the questions about the oil pressure.

What does it make cold?

What does it make hot at idle?

What does it make hot at 2000 RPM?

What does it make hot on the road?

... Have you tried changing the oil, or when was it done last. I've had oil break down and drop the pressure, not too much, but enough that when I changed it the pressure went up a noticable amount.

quote Originally posted by 86GT3.4DOHC: What he's talking about will cost about $30. Unless he does the pump too, then $30 more.

I was thinking the exact same thing. The repair he want to do is only about 60 bucks total with gaskets and everything and you guys want him to go out and drop 500 bucks on a junk yard motor that still might not last a year. Well if your gonna go out and spend 500 go out and do it right and spend an extra 400 and get a 3800 SC.. LOL.

quote Originally posted by 86GT3.4DOHC: What he's talking about will cost about $30. Unless he does the pump too, then $30 more. You still havent answered any of the questions about the oil pressure. What does it make cold? What does it make hot at idle? What does it make hot at 2000 RPM? What does it make hot on the road? ... Have you tried changing the oil, or when was it done last. I've had oil break down and drop the pressure, not too much, but enough that when I changed it the pressure went up a noticable amount.

What does it make cold?
At idle it’s about 40 psi & about 60 psi at around 2500 rpm.

What does it make hot at idle?
10 to 15 psi with the light going on and off some times

What does it make hot at 2000 RPM?
Right at 40 psi

What does it make hot on the road?
Just was looking at it this morning on my way in to work. At about 2500 rpm, it’s in the 40 to 45 psi mark

Have you tried changing the oil?
Yes, that was the first thing I tried

When was it done last?
Middle of November I took it to one of these Texaco oil change places. Where I had them/me put 10w/30w high mileage synthetic. I don’t normally go to these places but it just opened and I know the owner. He and I change the oil and filter. This was after the drop in pressure.

As an added note:
Two months before I had changed the oil using Mobel 1 high mileage synthetic and filter as I have for over a year now.

Also, my pressure up to this point has been around 20 to 30 psi hot at idle. Then one morning I when I got off the freeway and was stopped at a light I noticed my oil light flashing. When I check my oil I had lost any and it’s not smoking. My first thought was it’s my oil pump. But when I came out from work and started the car the pressure was back up. Get almost home the engine is hot now stop at a light and very low pressure. So I thought may be some dirt is plugging something up and so I change the oil again. Now I can watch the oil pressure drop as the engine warms up. Again no smoke, no knowing, I may just be worrying to much. I’ve been driving it everyday to and from work (29 miles round trip) for more than a month now.

Anyway thanks for the help,
Chuck

Maybe the oil pressure sending unit is going bad. Might try that first if it is not too expensive.

As far as your hot oil pressure, it is pretty close to my 1985 S10 Blazer with a 2.8L. 175K miles. It runs 40 psi cold, then drops to 10-15 psi at idle. I'm going to drive it until it gives up the ghost.

[This message has been edited by Hudini (edited 12-14-2006).]

You know, given that the oil light isnt constnatly on, and you have good oil pressure at running speeds, I would reccomend not touching anything.

Its highly likely the engine will continue to run like this for a long time. I have had 2 2.8L's with simular pressures. One I put lucas in, not a ton, but some, to keep the oil from thinning out so much when hot, and ran it for a very long time, at one point for 4 months I was driving it to and from work every day, at 100 miles a day. I put probably 10,000 miles on it before I sold it, with still the same pressures as when I started. The other also ran for a very long time, I did not do anything to it, just ignored the oil light when it flickered sometimes at idle.

I think your best bet at this time is to do nothing unless you start hearing knocking noises. Since you are planning on replacing it before too long, you are more likely to hurt it than help it over its current situation.

quote Originally posted by Hudini: Maybe the oil pressure sending unit is going bad. Might try that first if it is not too expensive. As far as your hot oil pressure, it is pretty close to my 1985 S10 Blazer with a 2.8L. 175K miles. It runs 40 psi cold, then drops to 10-15 psi at idle. I'm going to drive it until it gives up the ghost.

lol - you are right. not one person asked for mechacial guage verification of the oil pressure....
and Fiero gauage are famous for inaccuracy....

quote Originally posted by Pyrthian: lol - you are right. not one person asked for mechacial guage verification of the oil pressure.... and Fiero gauage are famous for inaccuracy....

They didn't have to, he stated it in his original post.

quote Originally posted by Chuckrock: The problem I am trying to correct: The car has 150,000 + miles on it, but has been very well kept. A few weeks ago my oil pressure took a dive when warm at idle. I check it with a mechanical gauge, hoping it was just the sending unit (not). When warm at idle I get about 10 to 15 psi. When cold or above about 900 to 1000 rpm everything is normal.