'04 GTO into '91 FBIRD starts, wont run?
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Car: '91 Formula LS1
Engine: 04 GTO LS1, slp maf/k&n cai
Transmission: built 700r4, 3500/10" hughes
Axle/Gears: moser, 3.73, eaton posi
'04 GTO into '91 FBIRD starts, wont run?
Hi,
Ive been reading alot of stuff about this swap & still cant get this to run, could it be wiring or something else i overlooked?
Does any one have any tips on wiring the '04 GTO into the '91 harness?
I have the '91 stock 700r4 built for racing w/ all the upgrades & the "Bowtie Overdrives" "tv made easy" kit instaled & on the intake is a K&N cold air kit w/ SLP 5 wire maf/iac, everything should be ready to go but its hard to start & when it starts it revs up to about 1800 orso for afew and then dies & i'm getting some interm. backfiring from the exhaust (black smoke) that smells really rich.
Ive tried afew ideas from posts on this site & others but still no luck, any help would be greatly appreciated!
Ive been reading alot of stuff about this swap & still cant get this to run, could it be wiring or something else i overlooked?
Does any one have any tips on wiring the '04 GTO into the '91 harness?
I have the '91 stock 700r4 built for racing w/ all the upgrades & the "Bowtie Overdrives" "tv made easy" kit instaled & on the intake is a K&N cold air kit w/ SLP 5 wire maf/iac, everything should be ready to go but its hard to start & when it starts it revs up to about 1800 orso for afew and then dies & i'm getting some interm. backfiring from the exhaust (black smoke) that smells really rich.
Ive tried afew ideas from posts on this site & others but still no luck, any help would be greatly appreciated!
Last edited by 91FBIRDLS1; 01-24-2010 at 04:42 PM. Reason: more info
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Re: '04 GTO into '91 FBIRD starts, wont run?
Have you tuned the VATS out of the PCM? and have you bypassed the car's VATS?
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Car: '91 Formula LS1
Engine: 04 GTO LS1, slp maf/k&n cai
Transmission: built 700r4, 3500/10" hughes
Axle/Gears: moser, 3.73, eaton posi
Re: '04 GTO into '91 FBIRD starts, wont run?
The pcm was just done by "wait4meperformance" no vats on the car itself, the motor starts & runs rough for few & then dies, I forgot to say that I dont have the o2 sensors in yet because i hafto get the bungs relocated, would that be part of the problem here?
I was told LS1's have a "limp home" mode incase you loose your o2's on the road, & that they will run w/o them for a while, is this true?
I was told LS1's have a "limp home" mode incase you loose your o2's on the road, & that they will run w/o them for a while, is this true?
Last edited by 91FBIRDLS1; 01-24-2010 at 04:49 PM. Reason: moe info
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Re: '04 GTO into '91 FBIRD starts, wont run?
I'm not sure on the O2's, IIRC the engine will run without them but i'm not 100% sure. Have you checked fuel pressure?
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Car: '91 Formula LS1
Engine: 04 GTO LS1, slp maf/k&n cai
Transmission: built 700r4, 3500/10" hughes
Axle/Gears: moser, 3.73, eaton posi
Re: '04 GTO into '91 FBIRD starts, wont run?
I thought it woudnt start at all if the vats was on, but he said thats one of the first things they did when they reprogramed it.
I havent checked the fuel pressure, but its a new walbro set-up in the tank & steel braided lines upto the rails so it s/b good there.
I havent checked the fuel pressure, but its a new walbro set-up in the tank & steel braided lines upto the rails so it s/b good there.
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Re: '04 GTO into '91 FBIRD starts, wont run?
O2 sensors dont cause the engine to die. Mines arent plugged in yet and the engine runs almost flawlessly... VERY rich but great idle.
Im guessing VATS too.
Im guessing VATS too.
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Re: '04 GTO into '91 FBIRD starts, wont run?
The car will start with VATS in, but it will shut off after about 5 seconds when it runs out of gas due to the fuel pump not running.
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Car: '91 Formula LS1
Engine: 04 GTO LS1, slp maf/k&n cai
Transmission: built 700r4, 3500/10" hughes
Axle/Gears: moser, 3.73, eaton posi
Re: '04 GTO into '91 FBIRD starts, wont run?
does that still apply if its a "stand alone" pump, not pcm controled?
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Re: '04 GTO into '91 FBIRD starts, wont run?
+1 for VATS
O2s are not even registered until the engine is warmed up. Even unplugged/missing they shouldnt cause it to stall out
O2s are not even registered until the engine is warmed up. Even unplugged/missing they shouldnt cause it to stall out
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Car: '91 Formula LS1
Engine: 04 GTO LS1, slp maf/k&n cai
Transmission: built 700r4, 3500/10" hughes
Axle/Gears: moser, 3.73, eaton posi
Re: '04 GTO into '91 FBIRD starts, wont run?
ok, so what about the rough/ crazy idle & backfire?
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Re: '04 GTO into '91 FBIRD starts, wont run?
you can be able to get that engine to run without the 02's and the maf. it wont run good without the maf. but it will run. as for backfiring that is another issue.did you do anything to the engine before you put it in. yes there is a limp home mode but it would keep running. vats i dont think will cause a rich backfire issue. have you tried to see if you loose spark or power to the pcm. sounds as though there is an issue with fuel or timing.
Last edited by one92rs; 01-24-2010 at 08:07 PM.
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Car: '91 Formula LS1
Engine: 04 GTO LS1, slp maf/k&n cai
Transmission: built 700r4, 3500/10" hughes
Axle/Gears: moser, 3.73, eaton posi
Re: '04 GTO into '91 FBIRD starts, wont run?
I only changed the oil pan & maf nothing else
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Car: '91 Formula LS1
Engine: 04 GTO LS1, slp maf/k&n cai
Transmission: built 700r4, 3500/10" hughes
Axle/Gears: moser, 3.73, eaton posi
Re: '04 GTO into '91 FBIRD starts, wont run?
its plugged in but how do you know if its bad or not?
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Re: '04 GTO into '91 FBIRD starts, wont run?
Try replacing it with another one, if it doesn't fix it then just take it back to the store and keep trying other things.
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Re: '04 GTO into '91 FBIRD starts, wont run?
What are you using as your ECM? And where did you get your tune from? The description below...
...sounds to ME like the tune is off. "Hard to start"/"backfiring" sounds like timing. "Revs to about 1800" and "(black smoke) that smells really rich" sounds like either the fuel curve or injector constant is outta whack. The only thing that would affect both (unless I'm missing something - which could be, it's kinda late) is the tune/ECM.
It wouldn't be a bad idea to double-check the fuel pressure at the rail as well, just to be sure.
Good luck.
but it's hard to start & when it starts it revs up to about 1800 or so for a few and then dies & i'm getting some interm. backfiring from the exhaust (black smoke) that smells really rich.
It wouldn't be a bad idea to double-check the fuel pressure at the rail as well, just to be sure.
Good luck.
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Car: '91 Formula LS1
Engine: 04 GTO LS1, slp maf/k&n cai
Transmission: built 700r4, 3500/10" hughes
Axle/Gears: moser, 3.73, eaton posi
Re: '04 GTO into '91 FBIRD starts, wont run?
I have the orig. '04 GTO harn. moded for stand alone wich (I think) is hooked up right according to my instructions from the seller also I just called "wiat4meperformance" who did pcm & they said its deff. not the vats or the fuel/ spark curves, they stand by their tunes 100% so they said to re-check all grounds & wiring, pull off the maf & get the o2's in, so thats whwt I'll try next I guess. iduunno, feels like I'm just graspin at straws here?
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Re: '04 GTO into '91 FBIRD starts, wont run?
Originally Posted by 91FBIRDLS1
also I just called "wiat4meperformance" who did pcm & they said its deff. not the vats or the fuel/ spark curves, they stand by their tunes 100%...
![doh](https://www.thirdgen.org/forums/images/smilies/doh.gif)
![Frown](https://www.thirdgen.org/forums/images/smilies/frown.gif)
I don't suppose you know of anyone fairly near you who has EFILive (or something similar) & could look at the program in the ECM?
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Re: '04 GTO into '91 FBIRD starts, wont run?
CRAP. I KNEW you were going to mention that name...
Myself personally, I wouldn't give a squirt of cold urine for one of his tunes - or his "customer service". I know that a number of people have come away with cars that run OK after having that outfit do the tune, but from everything I've read, it's pretty much a crapshoot. ![Frown](https://www.thirdgen.org/forums/images/smilies/frown.gif)
I don't suppose you know of anyone fairly near you who has EFILive (or something similar) & could look at the program in the ECM?
![doh](https://www.thirdgen.org/forums/images/smilies/doh.gif)
![Frown](https://www.thirdgen.org/forums/images/smilies/frown.gif)
I don't suppose you know of anyone fairly near you who has EFILive (or something similar) & could look at the program in the ECM?
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Car: 91 Formula ex-1/4 mi. car
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Re: '04 GTO into '91 FBIRD starts, wont run?
SO WHAT YOUR TELLIN ME IS THAT I JUST GOT SCREWED ON THAT TUNE JOB & I SHOULD PAY SOMEONE ELSE TO DO IT AGAIN!
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Car: 91 Formula ex-1/4 mi. car
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Transmission: built 700R4 w/ 10" HUGHES 3300stall
Axle/Gears: MOSER AXLES, 3.73 w/ posi
Re: '04 GTO into '91 FBIRD starts, wont run?
i had a good friend who went to wiat4meperf. & his was great! thats the only reason I went there.
so i should send it back to be redone or find someone else & pay more? i dont get it why is it so hard to find someone to program a pcm right?
so i should send it back to be redone or find someone else & pay more? i dont get it why is it so hard to find someone to program a pcm right?
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Re: '04 GTO into '91 FBIRD starts, wont run?
yes a pcm can be locked. they do that so someone else cannot read there tune. i used to tune my 02 silvy with hp tuners. i was taught by some that still tunes today and is pretty darn good at it. yes they lock them. from my experience on another board which was performancetrucks.net he had a bad wrap.
no it doesnt mean you got a **** tune at all. but i would send it back and have them check it. all they know is at the end of loading it says tune was succesful. they did not test it.
no it doesnt mean you got a **** tune at all. but i would send it back and have them check it. all they know is at the end of loading it says tune was succesful. they did not test it.
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Car: 91 Formula ex-1/4 mi. car
Engine: LS1/LS6 SLP maf K&N cai 3" exh
Transmission: built 700R4 w/ 10" HUGHES 3300stall
Axle/Gears: MOSER AXLES, 3.73 w/ posi
Re: '04 GTO into '91 FBIRD starts, wont run?
I agree that it sounds like the tune is off sum how, too much fuel not enough spark or sometin along those lines, but I really dont want to send this back again! WTF!
should i just go back to stock w/ the fuel & spark parameters or do I need it tuned for altitude?
I'm still gonna check fuel pressure@ the rails & see if thats off any, it shouldnt be cuz i have a new walbro pump, but none the less I wanna do it just to know 4 sure.
should i just go back to stock w/ the fuel & spark parameters or do I need it tuned for altitude?
I'm still gonna check fuel pressure@ the rails & see if thats off any, it shouldnt be cuz i have a new walbro pump, but none the less I wanna do it just to know 4 sure.
Last edited by THADURTYBIRD; 01-25-2010 at 09:37 PM. Reason: more info
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Re: '04 GTO into '91 FBIRD starts, wont run?
Originally Posted by THADURTYBIRD
I agree that it sounds like the tune is off sum how, too much fuel not enough spark or sometin along those lines, but I really dont want to send this back again! WTF!
should i just go back to stock w/ the fuel & spark parameters or do I need it tuned for altitude?
I'm still gonna check fuel pressure@ the rails & see if thats off any, it shouldnt be cuz i have a new walbro pump, but none the less I wanna do it just to know 4 sure.
should i just go back to stock w/ the fuel & spark parameters or do I need it tuned for altitude?
I'm still gonna check fuel pressure@ the rails & see if thats off any, it shouldnt be cuz i have a new walbro pump, but none the less I wanna do it just to know 4 sure.
![Wink](https://www.thirdgen.org/forums/images/smilies/wink.gif)
(Yes, I KNOW you can also do a speed-density tune, but that's just a "semi-educated" guess, & not especially helpful up here where you can go from 5,000' to 11,000' in a couple of hours or less...)
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Car: 91 Formula ex-1/4 mi. car
Engine: LS1/LS6 SLP maf K&N cai 3" exh
Transmission: built 700R4 w/ 10" HUGHES 3300stall
Axle/Gears: MOSER AXLES, 3.73 w/ posi
Re: '04 GTO into '91 FBIRD starts, wont run?
I just thought of this, could it be the stock 3rd gen. 5.0 fuel filter under the car ? gonna remove it & make a shunt to fill the gap that threads on in its place & drain the old gas at the same time, since its been sittn for over 2 years now
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Re: '04 GTO into '91 FBIRD starts, wont run?
A blocked filter/bad gas will not cause it to run rich
Clogged filter will cause a lean condition, and bad gas will make it run like poo. You will be able to smell it
Clogged filter will cause a lean condition, and bad gas will make it run like poo. You will be able to smell it
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Car: '91 Formula LS1
Engine: 04 GTO LS1, slp maf/k&n cai
Transmission: built 700r4, 3500/10" hughes
Axle/Gears: moser, 3.73, eaton posi
Re: '04 GTO into '91 FBIRD starts, wont run?
yeah i agree it would/ could cuase it to be hard to start & or stall out due to lack of gas though & I also think that its not only a bit redundant but not rated for the press. of the walbro.
I'm thinkin that its stallin out for those reasons(maybe others?) but then theres raw gas left in the system & the next time it starts it backfires a bit too & ifso thats poss. why its smellin so rich aswell? just a guess at this point
I'm thinkin that its stallin out for those reasons(maybe others?) but then theres raw gas left in the system & the next time it starts it backfires a bit too & ifso thats poss. why its smellin so rich aswell? just a guess at this point
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Re: '04 GTO into '91 FBIRD starts, wont run?
Lets put the threads together so we dont cover the same info twice
http://www.ls1tech.com/forums/conver...ont-run-2.html
Ok, you need a filter, two wont hurt, but you only need one. The second wont impede flow that much to make any difference unless its the original with 200,000 miles on it. Its unlikely the pressure rating of the filter has any effect on operation. That filter was used in all 3rd gens, CFI, V6, carb, TBI, TPI along with a slew of other GM vehicles of both high and low pressure systems
Im still leaning to a bad tune, but install a ALDL connector and pull the codes. We need to have something to work with
http://www.ls1tech.com/forums/conver...ont-run-2.html
Ok, you need a filter, two wont hurt, but you only need one. The second wont impede flow that much to make any difference unless its the original with 200,000 miles on it. Its unlikely the pressure rating of the filter has any effect on operation. That filter was used in all 3rd gens, CFI, V6, carb, TBI, TPI along with a slew of other GM vehicles of both high and low pressure systems
Im still leaning to a bad tune, but install a ALDL connector and pull the codes. We need to have something to work with
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Car: 91 Formula ex-1/4 mi. car
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Axle/Gears: MOSER AXLES, 3.73 w/ posi
Re: '04 GTO into '91 FBIRD starts, wont run?
cool I'm workin on gettn codes, if any? I'll post 'em up here, in the mean time i gotta finish up my trans pan & other loose elect. ends before i can go any further here.
should be good to go by this w/e
should be good to go by this w/e
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Re: '04 GTO into '91 FBIRD starts, wont run?
Quick question, did you have the PCM tuned for an auto or manual?
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Car: 91 Formula ex-1/4 mi. car
Engine: LS1/LS6 SLP maf K&N cai 3" exh
Transmission: built 700R4 w/ 10" HUGHES 3300stall
Axle/Gears: MOSER AXLES, 3.73 w/ posi
Re: '04 GTO into '91 FBIRD starts, wont run?
they were supposed to del. the trans. in order to run my 700r4 that was set up for racing w/ the last motor i had in the car(used to be a 12sec. 1/4mi. car)
now im wonderin what they really did after hearin all the bad publicity about the "wait4meperformance" guys, i heard they were really good before i got mine dun.
figures!
now im wonderin what they really did after hearin all the bad publicity about the "wait4meperformance" guys, i heard they were really good before i got mine dun.
figures!
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Re: '04 GTO into '91 FBIRD starts, wont run?
When I was wiring up mine i noticed some of the wires were pretty close to a heat source. When I cleaned up the wiring and moved them away the car ran perfectly! Heat causes resistance in the wires which in turn will throw false codes if not properly handled and installed.
#36
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Transmission: built 700r4, 3500/10" hughes
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Re: '04 GTO into '91 FBIRD starts, wont run?
ok, so i got the trans pan on (hughes deep alum.) & finished up sum of the wiring stuff & its still really hard to start to the point it drains the batt. i hafta crank it 3-5 times before it starts, when it does it revs up to about 1500-1800 rpm then dies, but no more back firing or rich smellin exh. now its runnin smoother before it dies & it acts like this with & w/o the maf. not really any diff.
its like the timing is way off or sumthin should i send the pcu back to wait4meperf. to be put back to stock perameters, or what?
its like the timing is way off or sumthin should i send the pcu back to wait4meperf. to be put back to stock perameters, or what?
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Car: '91 Formula LS1
Engine: 04 GTO LS1, slp maf/k&n cai
Transmission: built 700r4, 3500/10" hughes
Axle/Gears: moser, 3.73, eaton posi
Re: '04 GTO into '91 FBIRD starts, wont run?
wich obdII code reader should i get for "04 gto swap?
#39
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Car: '91 Formula LS1
Engine: 04 GTO LS1, slp maf/k&n cai
Transmission: built 700r4, 3500/10" hughes
Axle/Gears: moser, 3.73, eaton posi
Re: '04 GTO into '91 FBIRD starts, wont run?
ok, I think I found the prob. or one of them? on the "C1" side of the harn. there are two orange wires #'s 19 & 20 my sheet says #19 goeas to "ign. 3 volt" & #20 to B+ so does #19 goto the 3rd gen ign. wire that geos to the coil from the key or to B+ ? right now I have it coming off the key'd ign. wire but I dont see any voltage when I turn the key, is this the prob here?
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Car: '91 Formula LS1
Engine: 04 GTO LS1, slp maf/k&n cai
Transmission: built 700r4, 3500/10" hughes
Axle/Gears: moser, 3.73, eaton posi
Re: '04 GTO into '91 FBIRD starts, wont run?
I was also wondering if the fuel pump needs to be "hooked into" the ls1 pcm? i have it running offf the 3rd gen harn. I was told that would work but ...?
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Car: 92 Firebird
Engine: Supercharged 6.0
Transmission: T56
Axle/Gears: 8.8 3.73
Re: '04 GTO into '91 FBIRD starts, wont run?
Not sure about the 4th gen body connectors
The 3rd gen fuel pump relay will run the LS1 pump from the LS1 PCM just fine. Relays dont care what controls them
The 3rd gen fuel pump relay will run the LS1 pump from the LS1 PCM just fine. Relays dont care what controls them
![Name: FuelControl.gif
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#42
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Car: '91 Formula LS1
Engine: 04 GTO LS1, slp maf/k&n cai
Transmission: built 700r4, 3500/10" hughes
Axle/Gears: moser, 3.73, eaton posi
Re: '04 GTO into '91 FBIRD starts, wont run?
thanx for the info but I already tried that too & yer right the fuel pump runs great regrd. of wich relay powers it, I dont think its a fuel iss. but I dont know what the psi is @ the rails yet.
I was wondering if the ls1 pcm needs to be able to "see" or "control" the fuel pump at all?
I was told that I hafto wire the pump into the ls1 harn. or it wont run (by the guy who sold it to me)
I was wondering if the ls1 pcm needs to be able to "see" or "control" the fuel pump at all?
I was told that I hafto wire the pump into the ls1 harn. or it wont run (by the guy who sold it to me)
Last edited by 91FBIRDLS1; 01-31-2010 at 11:44 PM.
#43
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Car: 92 Firebird
Engine: Supercharged 6.0
Transmission: T56
Axle/Gears: 8.8 3.73
Re: '04 GTO into '91 FBIRD starts, wont run?
The PCM gives 12v to engage the fuel pump relay. The relay takes care of the rest
You can engage it via toggle switch for testing purposes if need be, but if it primes at all (you can hear it clearly) then its doubtful your problem is there
Did you pull the codes yet?
You can engage it via toggle switch for testing purposes if need be, but if it primes at all (you can hear it clearly) then its doubtful your problem is there
Did you pull the codes yet?
#44
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Car: '91 Formula LS1
Engine: 04 GTO LS1, slp maf/k&n cai
Transmission: built 700r4, 3500/10" hughes
Axle/Gears: moser, 3.73, eaton posi
Re: '04 GTO into '91 FBIRD starts, wont run?
HOLY CRAP!!! I freekin fig'd it out & got it running, sounds F'n awesome! so this whole time it was the relay pack that was spliced into the '04 harness to get power to all the things that need it, like the fuel pump for instance & the fan for another.
so all this time ive been fighting bad electronics(relays) it turns out i dont even need the relays that were spliced into the haness at all & the stock 3rd gen fuel relay was shot(i guess) so i replaced it and ran a new batt+ w/ fuse holder to it & BAM! she roars like a tiger!
so the thing to take away from all of this is that not only does the stock 3rd gen. relay work just fine & you dont need abuncha crap added into & hanging off of the harness(like a big *** relay pack) BUT, the LS1 "PCM" needs "see" or "control" (so to speak) the pump in order to keep the motor going correctly or else it doesnt get enough fuel & the motor runs like *** & dies a few seconds after startin.
thanx again to every one for all yer help with this & I will most likely still be around here as I STILL have sum issues to work through yet! & I really kinda like this site!
so all this time ive been fighting bad electronics(relays) it turns out i dont even need the relays that were spliced into the haness at all & the stock 3rd gen fuel relay was shot(i guess) so i replaced it and ran a new batt+ w/ fuse holder to it & BAM! she roars like a tiger!
so the thing to take away from all of this is that not only does the stock 3rd gen. relay work just fine & you dont need abuncha crap added into & hanging off of the harness(like a big *** relay pack) BUT, the LS1 "PCM" needs "see" or "control" (so to speak) the pump in order to keep the motor going correctly or else it doesnt get enough fuel & the motor runs like *** & dies a few seconds after startin.
thanx again to every one for all yer help with this & I will most likely still be around here as I STILL have sum issues to work through yet! & I really kinda like this site!
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Car: 91 Formula ex-1/4 mi. car
Engine: LS1/LS6 SLP maf K&N cai 3" exh
Transmission: built 700R4 w/ 10" HUGHES 3300stall
Axle/Gears: MOSER AXLES, 3.73 w/ posi
Re: '04 GTO into '91 FBIRD starts, wont run?
so far it looks like the tune i got from wait4meprf. is gonna be ok afterall, the car seems to be runnin good in the shop but well see how it runs on the street? i'll hafta post sum pix of her on here.
CANT WAIT TO DRIVE THE OLD GIRL AGAIN!!!
CANT WAIT TO DRIVE THE OLD GIRL AGAIN!!!
#46
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Car: '91 Formula LS1
Engine: 04 GTO LS1, slp maf/k&n cai
Transmission: built 700r4, 3500/10" hughes
Axle/Gears: moser, 3.73, eaton posi
Re: '04 GTO into '91 FBIRD starts, wont run?
WTF! now my fuel pump wont run at all unless i "jumper" it, but the motor still wont start even with the pump hot wired & it doesnt look like theres any spark either.
is it poss. i fried the ecm or something?
is it poss. i fried the ecm or something?
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Car: 92 Firebird
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Re: '04 GTO into '91 FBIRD starts, wont run?
If you have to jumper the relay and it works, then the PCM is not sending the proper signal to engage
PCM damage is possible, but it will throw a code. Did you scan the codes yet?
PCM damage is possible, but it will throw a code. Did you scan the codes yet?
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Re: '04 GTO into '91 FBIRD starts, wont run?
Possible see what codes have set in the system and go from there.
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Car: Trailblazer EXT 4.2 (Firebird Form)
Engine: 5.1 4bbl
Transmission: 700R4 Mega Raptor Level 4
Axle/Gears: 2.73
Re: '04 GTO into '91 FBIRD starts, wont run?
too much to read, but did you hook up a scanner to see if there are any codes stored? you did upgrade everything right? the conversion is a complete OBII setup?
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Car: 92 Firebird
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Re: '04 GTO into '91 FBIRD starts, wont run?
too much to read
He hasnt reported back in nearly 3 weeks, so either he gave up or the issue was something simple and he figured it out
Since we were focusing on his fuel control circuit which was very simple, chances are good he figured it out