Hey i got a gta with a 350 and an iroc with a 350 and both cars do the same thing, in the extreme cold weather when i start the cars on occasion they start right when i turn the key, but now thats its summer (cars have done this since i have owned them) i have to hold the key for a bit................then it starts up poorly most of the time, sometimes by pumping the gas it helps but usually it starts up putting to life then roars to idling perfectly while in the process realeases a huge cloud of smoke out the back. only time car stats right away is if i have just turned it off and start it within 2 min. does anyone else have this problem and if so how it can be fixed?? thanks

 

Sounds like you've never cleaned or replaced your fuel injectors...are they 20 years old? Possible you don't have the fuel lines primed and adequate pressure, either. Could be one of those, or both, in my opinion. A fuel pressure guage would answer the 2nd possibility.

 

try letting the pump prime first ... next maybe check the fuel preausre when primeing , etc

 

thanks im going to hook up a fuel pressure guage up soon to test my problem so see if in fact that is it, i have been told by my mechanic who was a gm trained one that it could also be a vacume leak, have u ever heard of this problem? Also when i check the pressure and if its low, what should i do, get a new fuel pump, a new fuel pressure regulator? i do use lucas fuel injector cleaner every so often and i recently checked the voltage on all the injectors and the read between 16 to 18 which i know is good. Problem really confuses me because both mine and my dads iroc do it

 

at this point it's only guessing ..so dont rush out and buy anything .

could be a leaky injector .... I don't think it's the regulator . Next time you go to start the car .... just turn the key ahead untill you har that relay click . Then the system is primed. See if it starts better after that ...

 

A lot of people will say this type of situation is normal. But it doesn't have to be. Install a fuel pressure guage and let the car sit for a while, or overnight. You'll probably see the pressure drop...and eventually it'll reach a pressure of 0. The fuel could be "leaking" one of three places as far as I know: fuel pump, pressure regulator, one or more injectors.

Checking the pressure with a guage is simple. Since some of the fuel lines are rubber in places (from pump, and return line), you can "crimp" them and try and hold the pressure to see if that "fixes" the leakdown. Then you'll have an idea of where the leak is occuring. Taking the fuel rail with injectors out, priming, and simply watching them leak or not is how I would go about checking that part.

I wouldn't hesitate to change the injectors. Yours are probably the type that can be rebuilt and cleaned cheaper than buying new http://www.cruzinperformance.com. If the leak is occuring via the pump, you could always rig up a check valve in the fuel line from the pump instead of going through the headache of replacing that piece.

Do some Searches...I'm sure many have had this same situation before.

I don't know anything about Lucas injector cleaner solvents. I wouldn't put anything like that in my cars. Sometimes, those solvents are not even compatible with certain injectors. Injectors are not cheap items...but they are an important part of the combustion process on these cars. A 20 year service life is doing well, I think.

 

I've got the same problem with my 88 GTA. The fuel pump was replaced before I bought it and I just replaced the fuel pressure regulator last weekend. Problem still exists. I checked the pressure and it's down. I'm starting to believe it's a injector due to the exhaust smelling like it's running rich. It's just a toy I bought and I'm just playing with it so it will be a while before I put new injectors in it.

 

I just went out and got a fuel pressure guage, im going to put it on soon once the car cools down a little, i am considering replacing the injectors soon because i know they are orignal. Which injectors would be best to use, go with factory delco injectors or aftermarket ones. i appriciate the help!

 

did a pressure test, left the guage on overnight and had a fuel pressure of pretty much 0!, injectors?

 

just did another pressure test and this is what i gather so far, i hooked up the guage the purged the system of pressure until the pressure was at 0. when i turn the key on i hear the pump turn on and the pressure jumps to about 19 to 21psi with just they key on, should this be a higher number? then i started the car after waiting seconds then it started and pressure was at 35 initially then jumped to 39 to 41 psi. is this the correct pressure or should it be higher? i do want to change the injectors because i believe they are the cause of my problems and i have been told by my mechanic who was gm trained that its the cause. what injectors are best to use and will be a direct fit while not costing a lot of money. While im doing this would it be a good idea to change the regulator to an adjustable one or would to stock one be just fine? i would appriciate any feedback to this thanks!

 

i'm having the exact same problem on my '88 GTA. i turn the key and always let the fuel pump build pressure through the lines before i even attempt to start it. usually to get it started i have to pump the gas even though it is fuel injected! if i cut the car off to run inside the store to get something then run right back out it will crank fine. ummm can we kinda find whats causing this so i can fix it on mine to? i'm thinkin of just gettin new Injectors but what size shoudl i get for a factory motor. should i go ahead and get bigger injectors due to future mods?

 

im pretty sure its injectors but while im at it ill prob replace the regulator as well. The injectors for a 350ci are 24lbs injectors. im still deciding on which ones to get tho

 

the injecotrs for a 350 are only 22lb's . Check the preasure again... after it's all up around 40ish and higher ... let it sit ( car off ) and see how long the preasure holds . If it drops right away , you may have a leaky injecotr or aleaky regulator.

 

You can isolate where the bleed down is occuring. Have you tried that yet?

From the sounds of it, probably the injectors, but a few methods can better determine that. Did you try those from my earlier post (crimping the lines)? Basically...once primed the fuel pressure will be in the mid to high thirties with all vacuum lines connected. If the drawdown occurs fast enough, you can watch the pressure drop on the gauge. May take 30 seconds, may take 30 minutes or what have you, but it will bleed down. Crimp both of the rubber fuel lines. If it still bleeds down. Then at least one or more injectors are leaking. If not...then its either the fuel pump, or fuel regulator. Uncrimp the line from the pump to the fuel rail. If it bleeds down...then at least the fuel pump is to blame. DO you see the picture??

You can have the injectors cleaned and rebuilt at the link I provided you previously. Cheaper than buying new, and as good as new. If you want new...I suggest the SVO Ford Racing Injectors.

 

thanks, im goning to do ur suggestion about crimping the lines tonite and see what happens. ill post the results soon

 

i crimped my fuel lines yesterday, watched pressure increase for 2 sec then within 20 min pressure was at 0 again.