1988 iroc starting problem
#1
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Car: 1987 IROC Z-28
Engine: L-B9
Transmission: 700R-4
1988 iroc starting problem
i have already changed the fuel pump and chack the fuel presure, it is fine but the car will not start without giving it some throttle, unless it hasnt been shut off for long, i changed the fuel pump relay and still no change, any ideas to what the problem is, i would like to fix this problem. it does throw the check engine light on occasion but nont often, also what work would be needed to put a 9.5.1 350 in place of the 305, i am not going for all out power just a bit more and maintain drivability. thanks
steve 704 796 1110 if you know what is wrong
steve 704 796 1110 if you know what is wrong
#2
Re: 1988 iroc starting problem
If you need to open the throttle to start the engine the problem may be flooding, not lack of fuel. Monitor fuel pressure while running and for several minutes after shutdown. If the pressure falls off to zero within 15-20 minutes there may be leakage from an injector(s) or the FPR. It's also possible the pump check valves are leaking but that is less likely with a new pump.
#3
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Re: 1988 iroc starting problem
Vader is on the right track. If it always starts faster if you give it throttle, it sounds like your engine is flooded. How much throttle are you giving it? Try holding it to the floor and starting it when you know it's not going to start good. If it starts much faster, then I'd say for sure you have leaky injectors/FPR.
My car only had 2-3 leaky injectors. And it was enough to have to give it two long cranks to start it, then it would stumble a bit from being flooded, and then idle ok.
Anyway, here are my fuel pressure readings when I turned the car off with leaky injectors:
My car only had 2-3 leaky injectors. And it was enough to have to give it two long cranks to start it, then it would stumble a bit from being flooded, and then idle ok.
Anyway, here are my fuel pressure readings when I turned the car off with leaky injectors:
#4
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Car: 1988 GTA
Engine: 305 tpi (LB9)
Transmission: WC T-5
Axle/Gears: 3.45 posi
Re: 1988 iroc starting problem
[quote=IROCThe5.7L;4522898]Vader is on the right track. If it always starts faster if you give it throttle, it sounds like your engine is flooded. How much throttle are you giving it? Try holding it to the floor and starting it when you know it's not going to start good. If it starts much faster, then I'd say for sure you have leaky injectors/FPR.
My car only had 2-3 leaky injectors. And it was enough to have to give it two long cranks to start it, then it would stumble a bit from being flooded, and then idle ok.
Mine is doing the exact same thing and I know for a fact that at least some of my injectors are leaking. The starting issue is exaclty what you're describing as but the car idles fine and runs great after the initial stumbling. I bought a set of Bosch III's that I'm going to put in whenever I get a free weekend. I was just curious what effects you saw overall after replacing the injectors. Any noticeable difference while driving or at idle, or just improved starts?
I'm not trying to hijack this thread, just curious about your results. Thanks!
My car only had 2-3 leaky injectors. And it was enough to have to give it two long cranks to start it, then it would stumble a bit from being flooded, and then idle ok.
Mine is doing the exact same thing and I know for a fact that at least some of my injectors are leaking. The starting issue is exaclty what you're describing as but the car idles fine and runs great after the initial stumbling. I bought a set of Bosch III's that I'm going to put in whenever I get a free weekend. I was just curious what effects you saw overall after replacing the injectors. Any noticeable difference while driving or at idle, or just improved starts?
I'm not trying to hijack this thread, just curious about your results. Thanks!
#5
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Re: 1988 iroc starting problem
I sent all 8 to be cleaned and flowmatched. I honestly couldn't tell a difference in idle or performance. But it started much better.
#6
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Car: 1986 IROC
Engine: 305 TPI
Transmission: 700R4
Re: 1988 iroc starting problem
if it still starts hard and there is a check engine light it may be a bad ECT sensor.
#7
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Car: 1987 IROC Z-28
Engine: L-B9
Transmission: 700R-4
Re: 1988 iroc starting problem
thakns guys i think i will just change all the injectors and the FPR and take care of it all
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