Im sure you know this as you have experiance with tuning and turbo cars, but whatever you do make sure its tuned very well. Since you've gone through the trouble of going to indiana to Darth's place before and putting the car on a dyno, combine the two and have Darth dyno tune it. I was going to do that last summer but I battled other issues with my car all last summer and never got the time and money.
Well tommorow is the day (hopefully). After 5 years of sitting, por-15 on everything, one 4 cylinder rebuild that then turned into a 2 1/2 year swap. Withe the help and guidance of this thread as well as others. Plus advice from several members and thier ideas and hard work, I will be attempting to start the beast from it's long slumber. She turns over quite nicely, now she needs to be fed. wish me luck. updates to follow.
dan
[This message has been edited by bonaduce (edited 03-08-2008).]
no luck today, got her to fire once back through the throttle body but that was it. will try again when i get a veiw minutes of time to spare.
dan
Dan, Heads up. I just wanted to let you know that there appears to be a intermittant problem with initial startup of the DOHC from those of whom I have built harnesses for. It involves the crank sensor polarity. I have had a 2 customers that had problems firing up due to the "fact" that the crank sensors on the DOHC may in some instances have reverse polarity. I wire them up as per factory specs but sometime it appears that the crank sensor polarity is reversed. A fix would be to simply swap out pin A wire and assign it to pin B on the crank sensor connector and vise versa. If you need more guidance, please PM me.
Hey B, I had the same issues with fire up, lilferrai, shared the crank sensor issue with me and sure enough after reversing those wires she fired right up. Erik built my harness and other than the polarity issue all seems fine.
by battery, I mean my battery I was useing is toast. I was trying to use that battery plus a 200amp booster. and there just isn't enuff battery there anymore.
Round 2, started this a.m. with a quick battery replacement, turn vehicle over, man is this engine tight. drew the battery down quickly. So set her back on charge and off to the yard to grab some fiero goodies. When I got back tried to start her again. still no joy. I have fuel, compression, and spark. question is would I still have spark if the crank sensor wires were reversed? as stated in previous post. I don't want to start tearing into the harness if I don't have to.
Round 2, started this a.m. with a quick battery replacement, turn vehicle over, man is this engine tight. drew the battery down quickly. So set her back on charge and off to the yard to grab some fiero goodies. When I got back tried to start her again. still no joy. I have fuel, compression, and spark. question is would I still have spark if the crank sensor wires were reversed? as stated in previous post. I don't want to start tearing into the harness if I don't have to.
thanks
dan
Yes..but the spark will be out of sync. Does the engine try to start at all? Have you confirmed the injectors are firing? I would try some starting fluid just to check that it's not the injectors. If it runs then, you should check your injector fuse. Make sure its a 10amp too
tried starting fluid to no avail, I did switch all the fuses but i will check them again (have to c if i can find that list to change). As for wanting to start, only got the one pop back through the intake last saturday. thanks for the help erik.
I read it as closely as I could, so may have missed this question, but....
I'm swapping a '92 DOHC into an '86 fiero platform - the fiero tranny outputs a sine wave from the VSS - is the '92 ECM expecting the same sine wave, or do I need to modify/buffer/whatever it before feeding it in?
It'd be nice if I could just make a simple parallel run from the VSS into the speedo buffer, and the stock '92 ECM!
Thanks.
------------------ 88 White Formula Auto - stock 87/88 Med Met Red V6 5spd "FormulaGT" Turbo 86 Black GT 4spd - stock
tried starting fluid to no avail, I did switch all the fuses but i will check them again (have to c if i can find that list to change). As for wanting to start, only got the one pop back through the intake last saturday. thanks for the help erik.
dan
Dan, I would try reversing the crank sensor wires. Its just a matter of cutting both crank sensor wires A and B a few inches fromt he crank sensor plug and just temporarily switching wires. If that works then just put an inch or two of shrink wrap on each wire, solder each wire and button up with a blowdryer or heat gun. Of course if you want to try a few other things first I would make sure you have the engine really grounded good to the chassis and of course you will want to have a direct ground from the battery to the engine as well.
I read it as closely as I could, so may have missed this question, but....
I'm swapping a '92 DOHC into an '86 fiero platform - the fiero tranny outputs a sine wave from the VSS - is the '92 ECM expecting the same sine wave, or do I need to modify/buffer/whatever it before feeding it in?
It'd be nice if I could just make a simple parallel run from the VSS into the speedo buffer, and the stock '92 ECM!
ok, started this am by switching the crank wires, now i am getting puffs of smoke out the exhaust, but still doesn't want to fire. I have used an entire can of starter fluid over the last to days. also disengaged the fp just in case of flooding. now og to search alldata to see if i can figure out if the injectors are actually firing. round three goes to the engine. if this was a boxing match, I would be getting my ass kicked. lol
Any reason the high and lows are reversed though? (it shows the VSS high going to the C203 as usual, then the VSS low from the ECM going to the same pin and vice versa on the other side)
Any reason the high and lows are reversed though? (it shows the VSS high going to the C203 as usual, then the VSS low from the ECM going to the same pin and vice versa on the other side)
Yeah high and low are reversed on the ECM. Hook it up like it is in the diagram.
Well today I got some diag tools from work, to dig a little deeper into the no start situation. Following the flow chart from alldata, step 1: disconnect cam sensor, did this no change. step 2: install fuel pressure gauge and read. Well here's where it gets interesting. I get 45 lbs when key is first turned to on position, then it slowly (over 2-3 seconds) drops to 10 lbs, and stays there. Turn key back off, retest, same thing. Turn engine over, retest, stays at 10 lbs. obviously a fuel related issue. Decided I might as well test the injectors, just in case. 2, 4, 6 all flash the noid, install gm tester j39021 and test ohms at injectors, all with in spec. Didn't test 1, 3, 5. couldn't find correct adapter harness, plus i assume if 3 are good, others should be also. So I am guessing that the fuel pressure regulator is most likely bad. fuel pump is new, 2.8 application was used. more to follow.
there is a thick rubber hose that is used as a dampener bewtween the fuel pump and pressure line coming out of the sending unit that can leak and cause loss of pressure
also if the injector(s) are leaking they can wash oil off the cylinder walls and cause loss of compression. What is your compression?
[This message has been edited by Erik (edited 03-17-2008).]
will have to check compression tommorow, another item i need to borrow from work. As for the "damper" hose, if it's the one i think it is, the one in the take, that was just replaced when i put the pump in. more to follow.
Don't get too wrapped up in testing the fuel system. If it doesn't start with a little quick spray of start fluid (1 to 2 seconds of spray, start the car within 15 seconds). Something is definatly messed up. I bench start all my engines with this method.
So, lets make sure that you have at some point addressed the quirky items on this engine:
Just to reaffirm, because the engine has coil packs, and the firing order may still be 1 2 3 4 5 6, however, the wiring on the coils is NOT 12 34 56! If you have the coils with the wire towers upright, from left to right they are 14 63 52, You can switch the wires on the individual coils with no effect. 14 can be 41 ect...
Cam timing must be set where the flats come up level on the banks 360 degrees of crank rotation away from eachother. In other words, when the front cam banks flats are up, the rears are down, and vice versa. Many people have made the mistake of having all four flats set straight up at the same time. The engine will run however, just not all that well.
You are getting a check engine light right? Have you run a scan on the car yet? I feel that as a requisit of doing a harness, you must get some form of scantool going. It's the most effective way of checking your harness for little mistakes. Big mistakes are easy to find, just look for smoke when you connect the battery Do you have VATS? is it disabled?
Im just trying to throw some ideas out there for you to make sure you covered these items.
quick question guys what size are the male fittings at the end of the fuel rail, fuel lines? Im going to be getting some braided flexible lines to go from my hard lines at the strut tower to the rail, so just gotta know what sizes im needing
Thanks for all the advice guys, I was looking for something complicated, and it turned to be something so simple I didn't even consider it. Thanks to fierobsessed who suggested th look at the wires on the coil packs, ALLDATA has listed as 1,4,3,6,2,5. switched wires to 1,4,6,3,5,2. two turns of the starter and she fired right up and ran. Again my thanks go out to Eric, for the harness and guidance; Lilferrari for providing me with schematics for his mounts and pulleys; Darth for burning me the chip; Blueshift, who i copied his original exhaust. And any others who have made this madness happen. And yes my fiero is a workbench, isn't yours?
Originally posted by bonaduce: Thanks to fierobsessed who suggested th look at the wires on the coil packs, ALLDATA has listed as 1,4,3,6,2,5. switched wires to 1,4,6,3,5,2. two turns of the starter and she fired right up and ran.
Umm.. you do realize that 1/4 3/6 2/5 is exactly the same as 1/4 6/3 5/2, right? It's a wasted spark system. Each coil is hooked up to two spark plugs and when it fires they both spark. It doesn't matter which poles they're on as long as they're on the right coil. Maybe you had them mixed up on the wrong coils and when you started over you got 'em right. Otherwise, it was a coincidence ;-)
[This message has been edited by Steven Snyder (edited 03-19-2008).]
Yes i realize that they fire the way you say. but as all I switched around was 3,6 coil and 5,2 and it fired right up. yeah it may be a coincedence, but i didn't change anything else that i have been trying for the last few days of trying to start. so i am chalking it up to that.
Even though it's a wasted spark system there is a correct way and a wrong way to hook up the leads as the current is flowing one way on one half cycle and the other on the other half so if you have them the wrong way around the current will be flowing the wrong way for the cylinder on it's compression stroke. In theory it should not make much difference but I guess it does.
Either way, way to go, bet you had a grin <------------------------this wide------------------------>.
Originally posted by ltlfrari: In theory it should not make much difference but I guess it does.
It doesn't make any difference. The polarity doesn't get reversed when it fires the coil the second time. One is ALWAYS going to be fired one way and the other on that coil is going to get fired the other way, regardless of compression stroke or otherwise. Remember, there is no cam position sensor involved in ignition control. The ICM has no idea which cylinder is on which stroke, and it has no way of knowing. The crankshaft position is 100% ambiguous in regard to compression vs exhaust strokes.
[This message has been edited by Steven Snyder (edited 03-19-2008).]
Interesting that that was the solution. My car has them wired 14 36 52. Specifically so that the wire routing is symmetrical...
Can you do us a favor and swap a pair of wires on one coil and test fire it again. I've swapped wires on individual coils lots of times and never had a problem, so I'm a little confused as to why that was the solution.
Originally posted by Fierobsessed: I've swapped wires on individual coils lots of times and never had a problem, so I'm a little confused as to why that was the solution.
I would guess that he redid the wires from scratch and probably just had a couple mixed up on the wrong coils before (maybe was looking at the diagram upside down; I've done that!). The poles don't make a difference because they don't switch; one is always going to fire one way anyway. The ICM has no per-cylinder control, only pairs..
as requested I did go outside this evening and switch the wires around again, first 3,6 then 2,5. and yes it started and ran fine as I was told it would do. so chalk that up to coincidence. maybe it was something else i missed and the wires had nothing to do with it. I will be the first to admit if i made a mistake in putting the wires on wrong, however I know for a fact that the wires were put on individually by cylinder and coil. You know what, I'm not gonna say anything else about this, the engine runs, sounds good, and hopefully by the end of the weekend will move under it's own power, so I can take it work and put it on a lift to work on. I'm getting to old to climb underneath. nuff said
Yes, that is a 4" plenum. It did change the sound a little. It's a little deeper and smoother. The old one was more raspy and higher pitched but not by much. On initial WOT the old intake was more responsive but from about 2800 to 3000 rpms you can tell a slight difference. However when you get to about 4K rpms it really picks up. I wanted to do this just to see if the TB was the main restriction of power for this motor. It is from 4K and up.
I had heard that the LQ1 was initially a 275hp engine and it was restricted due to possible trans failures at the time of development. So I was wondering what did GM do different to bring the power down? I need to get it to the dyno and see if there is a difference. I ran one before but I've done so much since that I couldn't say this alone could make all the difference.
I'm thinking about changing the cam timming again because I think I lost some power from last time but reliability was an issue. I don't know yet if I will or not, but I am curious to see.
Anyway I am looking into getting the Computer changed and tuned...I'm still running the stock OBDII computer.
Congrats on getting the car started!! I had on heck of a time too!
On another note I just found the impossible! a 92 3.4L DOHC California 5 sp grand prix!! It has a tranny problem, but I am gonna buy it anyway! If nothing else I'll have a spare engine, complete wiring harness, stock AIR pump (YAHOO), 5 speed stock e-prom. I know the refs will ask what the donor car was/is.
Not sure yet, the lady said the "plug" came out of the tranny and something happened to it. I won't be able to pick the car up until next Monday, or even see it for that matter. She has to leave town for a funeral. RUNDLC
Do you have VATS? is it disabled?
