91 z28 can someone help me
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Car: 1992 convertible camaro 1992 z28
Engine: 305 tbi 5.0 tpi
Transmission: 700r4 700r4
Axle/Gears: 2:73 2:73
91 z28 can someone help me
Okay I have a 91 z28 with a 350 swapped t5. Old owner put in some ford 19lb injectors.fuel pressure is bumped up to 54 psi I'm running rich or maybe lean cause there's a strong gas smell coming out of the exhaust failed smog. Also on a cold start it doesn't idle high or fast just idles at 650 with a slight surge. Also going 15 miles it jerks.higher speeds it runs good. What could cause it not to idle high on cold starts all my other camaros did it also my buddies z28 does it but this won't doesnt idle high on cold starts any help would be great
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Car: 1992 convertible camaro 1992 z28
Engine: 305 tbi 5.0 tpi
Transmission: 700r4 700r4
Axle/Gears: 2:73 2:73
Re: 91 z28 can someone help me
I put on new wires, spark plugs and coil also has a new distributor new cts a month old 02 sensor
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Car: 1992 convertible camaro 1992 z28
Engine: 305 tbi 5.0 tpi
Transmission: 700r4 700r4
Axle/Gears: 2:73 2:73
Re: 91 z28 can someone help me
Switched iac with my buddies still no change. Also switched tps with him same thing
#6
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Car: 1992 convertible camaro 1992 z28
Engine: 305 tbi 5.0 tpi
Transmission: 700r4 700r4
Axle/Gears: 2:73 2:73
Re: 91 z28 can someone help me
Both computers are for a 350 the car is a stock 350 car just the tranny and injectors are different. Yes no code. Well when I drove it back from a 3 hour trip the check engine light came on after I shut the car off and turned it on but went off after a couple of miles it was for the egr but the egr and solenoid are brand new the ses light hasn't came on anymore
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Car: 1989 Firebird Formula
Engine: 383 Stealth Ram
Transmission: 700R4
Axle/Gears: 3.73 9 bolt Posi
Re: 91 z28 can someone help me
I agree. Get the correct fuel injectors in there and lower the fuel pressure to about 43psi. Pull the battery to reset the computer, plug it back in, and then see how it behaves. You shouldn't start with something messed up and try and to compensate for it.
#9
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Car: 1992 convertible camaro 1992 z28
Engine: 305 tbi 5.0 tpi
Transmission: 700r4 700r4
Axle/Gears: 2:73 2:73
Re: 91 z28 can someone help me
I've searched on this forum and seen people running 19lb ford yellow top injectors with high fuel pressure. Something about those injectors tested at lower pressure I think it was 37 or 38 and gm is at 43.5
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Car: 1989 Firebird Formula
Engine: 383 Stealth Ram
Transmission: 700R4
Axle/Gears: 3.73 9 bolt Posi
Re: 91 z28 can someone help me
What is the duty cycle of your 19lb injectors running at 54psi?
#12
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Car: 88' IROCZ
Engine: 388 TPI Motown 350 Race block
Transmission: 700R4
Axle/Gears: 2.77
Re: 91 z28 can someone help me
Ford & GM PCM fuel programming is not the same, couple that with how they rate injector flow @ 85% duty cycle at different psi and you'll see why it necessary to raise/lower the pressure, but that can affect other things such as spray pattern.
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Car: 1990 G92 IROC Z Miniram
Engine: 388cu 6.4 Liters
Transmission: G-Force T5
Axle/Gears: 3.73 Gears
Re: 91 z28 can someone help me
Install the 22lbs injectors. Get a chip for the 350 with the torque converter lockup turned off. This is the right way to go without trying to short cut it. Its searching for an automatic trans.. Make sure the knock sensor and EGR are for 90-92 TPI.
What year of car did the engine come out of?
What year of car did the engine come out of?
Last edited by VincentZ28; 01-01-2013 at 09:02 AM.
#14
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Car: 1992 convertible camaro 1992 z28
Engine: 305 tbi 5.0 tpi
Transmission: 700r4 700r4
Axle/Gears: 2:73 2:73
Re: 91 z28 can someone help me
It's the stock engine only thing that was changed was the fuel injectors and the automatic transmission was swapped for a stick
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Car: 91' Firebird SOLD
Engine: 350 TPI +bolt-ons
Transmission: 700r4
Axle/Gears: 3:42
Re: 91 z28 can someone help me
The Ford injectors are rated the same as the GM, I have been through this many,many times. I know for a fact my Ford 24lb blue injectors are TRUE 24lb/hr just like GM. He needs a chip for a 350 with a five speed conversion. The injector size can be adjusted in the chip. The timing tables are also different between auto and stick, many differences there.
Last edited by ninetyone; 01-01-2013 at 04:44 PM.
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Car: 91' Firebird SOLD
Engine: 350 TPI +bolt-ons
Transmission: 700r4
Axle/Gears: 3:42
Re: 91 z28 can someone help me
Okay I have a 91 z28 with a 350 swapped t5. Old owner put in some ford 19lb injectors.fuel pressure is bumped up to 54 psi I'm running rich or maybe lean cause there's a strong gas smell coming out of the exhaust failed smog. Also on a cold start it doesn't idle high or fast just idles at 650 with a slight surge. Also going 15 miles it jerks.higher speeds it runs good. What could cause it not to idle high on cold starts all my other camaros did it also my buddies z28 does it but this won't doesnt idle high on cold starts any help would be great
#18
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Car: 1990 G92 IROC Z Miniram
Engine: 388cu 6.4 Liters
Transmission: G-Force T5
Axle/Gears: 3.73 Gears
Re: 91 z28 can someone help me
Since you live in California like I do, do it right so you can pass smog..
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