Starts but won't stay running.
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Joined: Jul 2013
Posts: 78
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From: Buffalo, NY
Car: 1987 Iroc Z28
Engine: 305
Axle/Gears: 3.73
Starts but won't stay running.
I have a 87 305 tpi. I bought this car with the motor out of it that was supposed to have been rebuilt. From the looks of the heads and the motor itself I believe it had been. That being said, before I put the motor back in the car I put all new components on it. Dist, plugs, wires, fuel injectors (South Bay 19lb), knock sen, oil pressure sen and switch, coolant temp sen and switch. I also converted it over to a serp setup with new alt, water pump, power steering pump and belt.
I dropped the motor in the car and got everything hooked up. The car wouldn't start and with the help of vetto on here narrowed it down to the fuel pump. Replaced that along with a new filter. There was a little gas left tin the tank so I put 10g of 91oct in and a bottle of stable in. The car fired right up bet then died often a out 5 sec.
After doing some double checking that the motor was at top dead center and that all the wire were in there correct spot I started it again. It did the same thing. Now if I keep my foot on the gas it will stay running but is very rich. I have tried to advance and retard the timing ( by turning the dist) but nothing is working. I have unplugged the esc and that doesn't work either. I can't get a idea of where why trimming is because I can't keep it running long enough to use the timing light.
The only thing that I can think of is that maybe my injector wires are mixed up? How would I go about checking this? Not firing in the right order?
The A.I.R system and heat/ac has been removed.
9th injector/ cold start has been removed.
EGR has been blocked off
The TB has the coolant bypass. There are only the 2 vac lines hooked to the TB
There are 2 vac line on the back of the plenum one closest to the from of the car goes to the FPR and the other goes to the T by the brake booster.
Not sure where to go from here. I checked for codes with a paper clip and the service engine light will only flash 12 once. Computer problem? I have not had any new chips burned for the mods that I have done yet. Could this be the problem?
I believe this is as much info as I can think to give so far.
Thanks for any help in advance
Keith
I dropped the motor in the car and got everything hooked up. The car wouldn't start and with the help of vetto on here narrowed it down to the fuel pump. Replaced that along with a new filter. There was a little gas left tin the tank so I put 10g of 91oct in and a bottle of stable in. The car fired right up bet then died often a out 5 sec.
After doing some double checking that the motor was at top dead center and that all the wire were in there correct spot I started it again. It did the same thing. Now if I keep my foot on the gas it will stay running but is very rich. I have tried to advance and retard the timing ( by turning the dist) but nothing is working. I have unplugged the esc and that doesn't work either. I can't get a idea of where why trimming is because I can't keep it running long enough to use the timing light.
The only thing that I can think of is that maybe my injector wires are mixed up? How would I go about checking this? Not firing in the right order?
The A.I.R system and heat/ac has been removed.
9th injector/ cold start has been removed.
EGR has been blocked off
The TB has the coolant bypass. There are only the 2 vac lines hooked to the TB
There are 2 vac line on the back of the plenum one closest to the from of the car goes to the FPR and the other goes to the T by the brake booster.
Not sure where to go from here. I checked for codes with a paper clip and the service engine light will only flash 12 once. Computer problem? I have not had any new chips burned for the mods that I have done yet. Could this be the problem?
I believe this is as much info as I can think to give so far.
Thanks for any help in advance
Keith
Member
Joined: Jun 2002
Posts: 181
Likes: 0
From: Bluegrass State
Car: 85 Trans Am
Engine: LB9
Transmission: Finally Fixed (T5)
Axle/Gears: 3.27
Re: Starts but won't stay running.
The injectors are batch fire on these, so its doubtful that you've got the wiring messed up. Did you put new injectors in? If yes, were they different sized than the original that were in the car? If, again, yes, then you maybe over fueling the car when it starts (esp if you went from 19# to 33# or something like that).
Thread Starter
Junior Member
iTrader: (4)
Joined: Jul 2013
Posts: 78
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From: Buffalo, NY
Car: 1987 Iroc Z28
Engine: 305
Axle/Gears: 3.73
Re: Starts but won't stay running.
I did buy new injectors but I went with new 19# for now. I got them from South Bay! The only thing I haven't replaces is the o2 sensor. I do have a new one just didn't put it I yet. Was going to wait for the new exhaust.
Joined: Apr 2005
Posts: 7,736
Likes: 14
From: Not in Kansas anymore
Car: 82 Z28
Engine: 383 SP EFI/ 4150 TB
Transmission: T400
Axle/Gears: QP 9" 3.73
Member
Joined: Jun 2002
Posts: 181
Likes: 0
From: Bluegrass State
Car: 85 Trans Am
Engine: LB9
Transmission: Finally Fixed (T5)
Axle/Gears: 3.27
Thread Starter
Junior Member
iTrader: (4)
Joined: Jul 2013
Posts: 78
Likes: 0
From: Buffalo, NY
Car: 1987 Iroc Z28
Engine: 305
Axle/Gears: 3.73
Re: Starts but won't stay running.
Yes I will do that next. I believe I found part if not the whole problem. I checked valve lash today and it was way out. When doing so I noticed that there is no oil going to the heads. I'll be installing a new oil pump tomorrow and finishing the valve lash.
Thanks
Keith
Thanks
Keith
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