OK I bought a 1986 SE with a 2.8. Hard start stumble, stumble, stumble. Sounds and feels like vac leaks galore. I have questions as in there are 1/2 inch hard metal pips that look like to be a brake booster line, but NOTHING attached to them. Also a few visibly bad connections or missing vac connections. See Photos. I am asking for help identifying missing connections, and bad connections, so I can learn about this motor. Anything Iron Duke I am the master but 2.8 nope. So please look at the photos and help me identify these.
Also the tail lights kinda work. They are Very Very Very Very dim. I can see the bulb filament slightly glow orange. One bulb socket was crimped on with blue crimp connectors. I'm wondering if one socket is bad or has a bad connection with it dim the entire system in the rear?
Thanks folks!
Curly
What is this entire module? It has like 5 bad vac connections on it.
Random not connected to anything electrical connector....What is it for?
What is this hardline for? Where does the vac line fit to the motor?
Same with this one? What for and where?
It's been a long time since I had a car with cruise. Are these vac line nipples or just bleed off openings? I forget.
Awesome....Thank you. This explains a lot. Just picked up a bunch of vac line. I'm going to replace everything that is rotted. There is a larger line that comes off the EGR solenoid, and runs to the fire wall. That thing is crumbling to dust.
Ok and cap that large tube. SO both large metal tubs shown are recall lines?
Yep. Those are it. Ok so plug em up. I Changed the lines from the EGR solenoid. Found some of the molded plastic lines broke. Coupled the breaks with some tubing. It almost looks like the hard lines against the trunk wall are rusted and have pin holes. When I pinch off the rubber tubing going to them the engine idle lowers. Plus they are really really rusty. I might need to find replacements for those.
At the dealership during recall repairs, this particular task was dealt with a couple of different ways (from what I've discovered on my own and other people's Fieros). The left side end of that tube connects to the filtered side of the air filter canister. In most recalls, it appears that the tube was left attached to the canister, and the right side end of the tube was capped. Sometimes though, it appears that the tube was disconnected at the canister, and the canister itself was plugged/capped. In this situation, then sure, the right side end of the tube could remain open, as the tube was no longer connected to anything. However, never assume that this is the method that has been utilized when you see an uncapped tube, because if the tube is still connected to the air filter canister, then filthy unfiltered air is being drawn directly into the intake system.
It almost looks like the hard lines against the trunk wall are rusted and have pin holes. When I pinch off the rubber tubing going to them the engine idle lowers.
I suspect those metal tubes along the trunk wall are usually overlooked when vacuum leaks are being searched for. With these cars getting older, and often rustier, pinholes in engine bay metal tubes will no doubt become more commonplace.
Any thoughts on the very very dim tail lights? Almost like there is some resistance somewhere.
Yes, check the harness ground located in the passenger side rear wheel well. You'll need to loosen the plastic wheel well cover to gain access. The ground harness is screwed to the upper frame rail, but it often gets corroded there and the harness then no longer grounds properly.
But hey, you should've known that, as it's the same rear harness that a Duke powered Fiero has.
quote
Originally posted by Curlrup:
My 4th Fiero... Anything Iron Duke I am the master...
[This message has been edited by Patrick (edited 03-28-2021).]
Random not connected to anything electrical connector....What is it for?
If you can unwrap the wire loom a bit and clean up the wires you will be able to see what colors the wires are. That should help you identify where it is supposed to go.
I can do that. Seems odd that a pretty decent size plug is taped up and hanging on the backside of the plenum. I should get a multi meter on the pins to see if there was s voltage.
Ok....Whew....Yep that ground was loose. I now have tail lights!. Also, amazing how that ground probably helped it run better. It ran better after new vac lines, I also did a quick fix and sprayed the hard vac lines with flex seal. Temp fix just to see if there is improvement by quickly plugging any and all pin holes. Yep , it starts better, runs smoother, less stumble, and no hesitation now. Question though. If it runs for a while, you shut it off, Let it sit for a few minutes, then come back it does not want to start until you try it a few times then it just pops off and purrs like there was no issue. Very strange.
Also mystery plug has been unwrapped please see photos.
Purple/white stripe, and orange is what the wires look like.
Also. My new to me Red SE and Juliet, my 88 Iron Duke Fiero I rebuilt.
Question though. If it runs for a while, you shut it off, Let it sit for a few minutes, then come back it does not want to start until you try it a few times then it just pops off and purrs like there was no issue. Very strange.
Something that's quite easy to check on the 2.8, but often ignored is fuel pressure. Not only do you want to see what the fuel pressure is while running, but you also want to see how quickly it drops when the fuel pump stops. The pressure should hold steady for quite awhile. If it starts dropping immediately, then perhaps an injector or two is leaking.
Good thing I have a guage. Ok. Time to check that next. Thank you sir! My 88 iron duke just runs and runs and runs since I rebuilt it. I worked out all of f the kinks. So my trouble shooting skills have lapsed. Coupled with an engine I'm not familiar with and I'm scratching my head a lot.
Also....it was converted to an R134a A/C system in 2002. Just found the sticker under the hood explaining that. So maybe the mystery plug is A/C related?
I believe the "mystery plug" is for the cold start injector.
The reason there's some confusion on the unplugged tube running along the firewall, is there were two different designs. The early design the metal tube plugged into the intake snorkel. The later design plugged into the side of the air filter canister.
During the recall, if memory serves, the early design snorkel was replaced with a new snorkel that had no inlet for that metal pipe. Thus the pipe was open on either end and didn't need to be capped.
The later design that plugged into the air filter was ignored and not capped off as well even though it fed directly into the filtered side of the air filter canister thus allowing unfiltered air into the engine. For that design, the best way to handle it is to put a rubber cap on the air filter canister in place of the rubber hose that went from the canister to the abandoned metal pipe.
Personally I removed the pipe when I used to have a post-recall Fiero but all of my current Fieros are as they were created Pontiac and remain uncut.
Interesting. So question. Do I need the cold start injector? I just did some searching and it looks to be something people delete since it's a pain in the arse sometimes. More and more I think that plenum will be coming off to see whats going on under it. My smoke machine is coming next week to hunt down any more vac leaks. Figured with twice as many vac lines as an 88 Iron Duke I needed a way to quickly find vac leaks.
Thanks folks I'm learning a lot here on this motor I have ZERO experience with.
Another thought on the start-stop-won't-start-again-for-a-while is the ignition module inside the distributor. IIRC the 4-bangers are entirely different in this regard, but the V6 is famous for issues with these. I'd pop the cover off the dizzy, unscrew the module, clean and apply new silicone heatsink grease from your local computer store, then careful tighten again. Also make sure its connector (connectors? I forget if they're combined) are nice and tight. If any of the above shifts due to thermal stress you won't get spark. Many owners carry a spare module, and recommend the Delco branded replacement vs. random house brand.
Another thought on the start-stop-won't-start-again-for-a-while is the ignition module inside the distributor. IIRC the 4-bangers are entirely different in this regard, but the V6 is famous for issues with these. I'd pop the cover off the dizzy, unscrew the module, clean and apply new silicone heatsink grease from your local computer store, then careful tighten again. Also make sure its connector (connectors? I forget if they're combined) are nice and tight. If any of the above shifts due to thermal stress you won't get spark. Many owners carry a spare module, and recommend the Delco branded replacement vs. random house brand.
-- A
That was next on my list. Spare ignition module. I ALWAYS keep a spare with. On a non distributor Iron Duke I can change them out by feel. Done it a few times, in the rain, and the dark, on the side of the road across the two 88 iron dukes I've owned.
The reason there's some confusion on the unplugged tube running along the firewall, is there were two different designs. The early design the metal tube plugged into the intake snorkel. The later design plugged into the side of the air filter canister.
During the recall, if memory serves, the early design snorkel was replaced with a new snorkel that had no inlet for that metal pipe. Thus the pipe was open on either end and didn't need to be capped.
I believe you're mistaken.
From what I understand, the now non-utilized metal tube on the firewall used to connect the filtered side of the air canister to the front valve cover of the 2.8 engine. This acted as the air intake for the PCV system. The problem is that under certain conditions, air flow temporarily goes the other way. There was a fear of oil collecting in this tube and eventually creating a fire hazard (due to the cat being located immediately below.) The recall eliminated the firewall tube from the equation, and instead, a shorter replacement metal tube is used to connect the front valve cover to a redesigned snorkel with an inlet just ahead of the throttle body. This allows any oil vapors (which are temporarily going the "wrong" way) to more easily be drawn directly into the intake system and burned in the cylinders.
Reinhart, if you have any links which contradict what I've stated, I'd honestly appreciate being corrected.
At the dealership during recall repairs, this particular task was dealt with a couple of different ways (from what I've discovered on my own and other people's Fieros). The left side end of that tube connects to the filtered side of the air filter canister. In most recalls, it appears that the tube was left attached to the canister, and the right side end of the tube was capped. Sometimes though, it appears that the tube was disconnected at the canister, and the canister itself was plugged/capped. In this situation, then sure, the right side end of the tube could remain open, as the tube was no longer connected to anything. However, never assume that this is the method that has been utilized when you see an uncapped tube, because if the tube is still connected to the air filter canister, then filthy unfiltered air is being drawn directly into the intake system.
[This message has been edited by Patrick (edited 03-30-2021).]
What's your explanation for the OP's post-recall picture with the metal firewall tube that dead ends at the snorkel?
It's not the best picture that the OP posted of that tube, but I already offered an explanation Here.
It is possible that the tube we're seeing is the end of the now unused firewall tube, but even so, that doesn't necessarily change anything I've stated in regards to what was modified for the recall. There would've originally been a rubber elbow attaching the firewall tube to the air filter canister.
Curly, can you please tell us where the other end of that tube goes?
quote
Originally posted by Curlrup:
What for and where?
[EDIT] Curiosity has gotten the best of me, and I've come across this diagram... supposedly of a pre-recall Fiero 2.8 PCV system. I have never ever (in 22 years of being here) seen a photo (rather than an illustration) of this type of setup where the firewall tube connects to the underside of the snorkel. Very strange. My '86 GT has the firewall tube (now capped on one end) connected to the filter canister. It was never at any time attached to a snorkel. It's nowhere near where the metal tube pictured above is located. Perhaps there were two different styles of pre-recall metal firewall tubes?
[This message has been edited by Patrick (edited 03-31-2021).]
[EDIT] Curiosity has gotten the best of me, and I've come across this diagram... supposedly of a pre-recall Fiero 2.8 PCV system. I have never ever (in 22 years of being here) seen a photo (rather than an illustration) of this type of setup where the firewall tube connects to the underside of the snorkel. Very strange. My '86 GT has the firewall tube (now capped on one end) connected to the filter canister. It was never at any time attached to a snorkel. It's nowhere near where the metal tube pictured above is located. Perhaps there were two different styles of pre-recall metal firewall tubes?
I can't get a good angle to get a good photo. However, the two hardlines I speak of are actually ONE tube. It runs along the firewall, behind the air cleaner, then makes a sharp bend around the air cleaner can and comes out the other side. So the two photos I posts were just the two ends of the same tube. Nothing is connected to the air cleaner or snorkle. So exactly like the illustration shows.
[This message has been edited by Curlrup (edited 03-31-2021).]
So the two photos I posts were just the two ends of the same tube.
Yes, it's the firewall PCV tube that's no longer used. The surprise (for me anyway), is that there appears to have been two different styles of these metal tubes. They both originally connected to the front valve cover, but on the other end, one originally connected to the air filter canister while the other apparently connected to the underside of the snorkel.
quote
Originally posted by Curlrup:
Nothing is connected to the air cleaner or snorkle.
Correct, sort of. That firewall metal tube is no longer connected to anything, because your engine has had the recall work done. But the replacement PCV tube pictured above now goes from the front valve cover to the replacement snorkel.
Update of sorts. Just had it out for a decent run. Running...decent. At low speeds, say 20 mph when you hit the throttle it hesitates and backfires. If I remember right that is a rich running condition. It also smells very exhausty. Is that a thing? exhausty? Smells rich
Yes the cold start injector has been deleted. There is a huge bolt threaded into the fuel rail.
Still waiting on my smoke machine to hunt down all vac leaks. There has to be more vac leaks.
Other than that it goes great on some hard pulls. Just low speed, it hesitates.
Also if you get on the gas at 55 mph it feels like it's running on a rough road. It's odd. Off the gas smooth. Get on it. it's rumbly. The whole car is rumbly like it's on gravel. More to come as I work through this thing.
More data. It was on a half tank after 48 miles of driving....topped it off to see how much it actually used. 5.5 gallons. So it's getting 8.72 MPG....something is boned. It's running rich for sure right?
***edit to say O2 sensor ordered****
[This message has been edited by Curlrup (edited 04-01-2021).]
I don't understand the significance of HTTPS... but I notice the images all open just fine if "Open image in new tab" is selected.
Because the site is now HTTPS browsers will refuse to load insecure or HTTP content that is trying to be displayed on the site. This is done so you do not have privacy leaks in your secure section. This is called mixed content. https://developer.mozilla.o...ck-all-mixed-content
Just did a pressure test on the fuel system. 45 PSI on key on (pump kick in) 37 PSI running, then leaked down to 25 PSI slowly over the course of 30 minutes, then I had to make dinner so I just unhooked everything and put it away.
When I attached the gauge on the fuel rail it was spraying fuel everywhere and it had been sitting for hours at that point so there was pressure there. By the time I got the gauge on it read 10 PSI. One click of the key and it shot up to 45 PSI and stayed there until I started it.
Apologies to Curly for going off on a bit of a tangent here, but this is something that's now affecting us all and needs to be resolved.
This is a bit over my head... but is making the PFF image server somehow "secure" a solution to this issue?
Interesting that the image in This post still displays just fine, even though it's also hosted at a non-secured site.
Yeah Sorry Curly.. however good post publicity
I was looking at that image and it occured to me that i am noticing the warning about insecure items in my browser. So perhaps im off base or it depends on browser settings. It loads fine on my laptop. Could be some redirect issues in the code as well? Im sure Cliff is on it and is more than capable of sorting it.
If you try to open an image as HTTPS it bricks. Tech is my thing so i like playing the wild speculation game while someone else is trying to solve the actual issue.
Probably should just move this to a different thread.
[EDIT] Curiosity has gotten the best of me, and I've come across this diagram... supposedly of a pre-recall Fiero 2.8 PCV system. I have never ever (in 22 years of being here) seen a photo (rather than an illustration) of this type of setup where the firewall tube connects to the underside of the snorkel. Very strange. My '86 GT has the firewall tube (now capped on one end) connected to the filter canister. It was never at any time attached to a snorkel. It's nowhere near where the metal tube pictured above is located. Perhaps there were two different styles of pre-recall metal firewall tubes?
Um you adamantly told me I was wrong when I said that in my first post. Now you're saying "*perhaps* there were two different styles of pre-recall metal firewall tubes" even though it has been confirmed by the 22P?
Me: "The reason there's some confusion on the unplugged tube running along the firewall, is there were two different designs. The early design the metal tube plugged into the intake snorkel. The later design plugged into the side of the air filter canister.
During the recall, if memory serves, the early design snorkel was replaced with a new snorkel that had no inlet for that metal pipe. Thus the pipe was open on either end and didn't need to be capped.
You: I believe you're mistaken. "
The only thing I was unsure of was how the recall handled the two designs. I wasn't unsure about the fact there were two designs.
[This message has been edited by reinhart (edited 04-02-2021).]
Ok. Used my fancy fancy scanner. Friend gave me. No codes. Stayed in open loop for a long time. Longer than a 4 cylinder. Then was popping in and out of closed loop a lot, then settled down. Again 4 cylinders running good don't do this. At least I haven't seen it. This scanner is new to me so it could be that too.
Once warm O2 sensor voltage was staying between .45 and .60. According to the manual a properly running engine should be jumping between .200 and .800.
Gonna PB blast all the plugs and redo all of the ignition this weekend.
