So close to driving it, help w/ running rough
04-20-2005, 03:34 PM
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Car: Depends on the day!
Engine: the kind that runs on money
Transmission: One that holds up, I hope
So close to driving it, help w/ running rough
When cold, very hard to start. Cranks up and dies off. Once I can get it running- after making it idle until warm up- idles fine. Some searching but not much. Giving it gas from a stop it stumbles/like a miss until it gets going then revs fine. I have a snap-on mt 2500 scanner but I really dont know what to look for. I did notice that the egr solenoid duty cycle never goes off of 0%.
04-21-2005, 09:25 PM
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Car: Depends on the day!
Engine: the kind that runs on money
Transmission: One that holds up, I hope
when I put the engine back in I put a brand new gm egr on. the egr solenoid has not been replaced. Wouldn't a clogged fuel filter be more of a problem in the higher rpm range?
04-21-2005, 09:52 PM
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Car: '86 Berlinetta
Engine: 350
Transmission: 700R4
Yes, it would be a problem in the higher RPM ranges, or when you are suddenly giving it gas (idling at a stop sign, then romp on it).
Also, what is the word on the fuel pump's reliability?
and to add to the list... what is your base timing set at (when you disconnected the EST connector to set your timing)
Also, what is the word on the fuel pump's reliability?
and to add to the list... what is your base timing set at (when you disconnected the EST connector to set your timing)
04-21-2005, 09:56 PM
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Car: Depends on the day!
Engine: the kind that runs on money
Transmission: One that holds up, I hope
base timing is on 6 degrees, that has been double checked. fuel pump not sure of, I have a fuel pressure gauge on it and it stays around 40 psi when running. I did notice that it drops some when I rev it up. I will put a new fuel filter on it and go from there.
04-21-2005, 10:14 PM
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Car: '86 Berlinetta
Engine: 350
Transmission: 700R4
After you shut the car off, how long does it take for the fuel pressure to bleed out?
The more I read your post over, the more I think about it being a leaky injector.
The more I read your post over, the more I think about it being a leaky injector.
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04-21-2005, 10:22 PM
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Car: Depends on the day!
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Transmission: One that holds up, I hope
If I turn the key on w/o cranking it the pressure goes to about 35 or 37. Turn the key off and go back to it in 20 or 30 minutes and it is about the same. Maybe a 2 - 3 psi drop. What is the norm on that if there is one?
04-22-2005, 10:36 AM
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Car: 88' IROCZ
Engine: 388 TPI Motown 350 Race block
Transmission: 700R4
Axle/Gears: 2.77
Originally posted by Notplayn
If I turn the key on w/o cranking it the pressure goes to about 35 or 37. Turn the key off and go back to it in 20 or 30 minutes and it is about the same. Maybe a 2 - 3 psi drop. What is the norm on that if there is one?
If I turn the key on w/o cranking it the pressure goes to about 35 or 37. Turn the key off and go back to it in 20 or 30 minutes and it is about the same. Maybe a 2 - 3 psi drop. What is the norm on that if there is one?
04-22-2005, 11:54 AM
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Car: Depends on the day!
Engine: the kind that runs on money
Transmission: One that holds up, I hope
I clocked the pressure drop this morning after changing the fuel filter. FP reading 40 psi, after an hour it was down in the low 20s.
I still dont know why when its cold it will crank, idles up and then comes down and cuts off. It will do this unless I hold the accelerator up around 1500 rpms. Once it starts to warm up it will idle, a little rough, but idles.
I still dont know why when its cold it will crank, idles up and then comes down and cuts off. It will do this unless I hold the accelerator up around 1500 rpms. Once it starts to warm up it will idle, a little rough, but idles.
04-26-2005, 10:51 PM
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Car: '86 Berlinetta
Engine: 350
Transmission: 700R4
take your injectors out by the rail after you pressurize the system (turn it on, then turn it off). Then find out which of the injectors leak unusually fast.
You can also turn the car on (keep spray away from the distributor!) to see the spray pattern. If some are spraying extra hard, in weird ways, etc... then you found the injector that is bad.
If none come up bad then you can go from there. There's a lot to the fuel system, yet not that much ... it's weird
You can also turn the car on (keep spray away from the distributor!) to see the spray pattern. If some are spraying extra hard, in weird ways, etc... then you found the injector that is bad.
If none come up bad then you can go from there. There's a lot to the fuel system, yet not that much ... it's weird
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