Trouble code ?
Thread Starter
Burning Brakes
Joined: Nov 2003
Posts: 844
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From: Cape Cod Ma
Trouble code ?
85' that i've been trying to get to run right after engine build.
I've got the car running very well when it wants too. When the car runs good, no code. Bad then a code light would come on. The problem is a bad missfire. Now the car (overnight) has trouble keeping an idle and it backfires out the exhaust very badly.
I have a 12 that i dont know what it is.
A 42 wich is a EST(electronic spark controller)
A 43 Knock sensor circuit
And a 54 wich is a fuell pump circuit ( low voltage )
The car was'nt runing when these were pulled..so that MAY solve the fuell pump problem. The pump is a new AC delco.
This stuff kinda points me in the direction that i have to replace the ECM or theres somthing wrong with it. But im not 100% on this so if someone can point me in the right direction that would be great.
I've got the car running very well when it wants too. When the car runs good, no code. Bad then a code light would come on. The problem is a bad missfire. Now the car (overnight) has trouble keeping an idle and it backfires out the exhaust very badly.
I have a 12 that i dont know what it is.
A 42 wich is a EST(electronic spark controller)
A 43 Knock sensor circuit
And a 54 wich is a fuell pump circuit ( low voltage )
The car was'nt runing when these were pulled..so that MAY solve the fuell pump problem. The pump is a new AC delco.
This stuff kinda points me in the direction that i have to replace the ECM or theres somthing wrong with it. But im not 100% on this so if someone can point me in the right direction that would be great.
Team Owner
Joined: Dec 2000
Posts: 90,675
Likes: 304
From: SE NY
Cruise-In II Veteran
A bad ECM is possible even though you are not getting either a ECM nor CalPac bad code.
The "12" is just an indicator of the start & end of the real trouble codes.
You might test the fuel line pressure to see if the pump is getting power throught the oil pressure switch at the rear of the intake base.
You could replace the EST module to see if that solves the other problems.
These would be cheaper than replacing the ECM, just in case it's ok.
The "12" is just an indicator of the start & end of the real trouble codes.
You might test the fuel line pressure to see if the pump is getting power throught the oil pressure switch at the rear of the intake base.
You could replace the EST module to see if that solves the other problems.
These would be cheaper than replacing the ECM, just in case it's ok.
Thread Starter
Burning Brakes
Joined: Nov 2003
Posts: 844
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From: Cape Cod Ma
Its dark and raining now so i couldnt check the pump power at the relay. When i turn the key on ( not run ) the pump dosent pressurize the system..making it very hard to start the car. All it did was spuddeer and that was it. Then i got a horable smell when i got out of the car.
More and more i look into this it leads to the ecm
More and more i look into this it leads to the ecm
Thread Starter
Burning Brakes
Joined: Nov 2003
Posts: 844
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From: Cape Cod Ma
I do have a Helms manual. And that may be one of the problems being the relay being that its intermitenly not suppling enough power to the fuell pump. That could be the code. But having all these other problems that are pointing to the ecm, all of a sudden, the ecm got fried and im thinking the problems with the spark i've been having, the ecm musta been week or working improperly reading the esc.
I will check he relay out tomarrow, just incase.
I will check he relay out tomarrow, just incase.
Race Director
Joined: Sep 2000
Posts: 17,298
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From: The Top of Utah
Originally Posted by redfast
I do have a Helms manual. And that may be one of the problems being the relay being that its intermitenly not suppling enough power to the fuell pump.
RACE ON!!!
Thread Starter
Burning Brakes
Joined: Nov 2003
Posts: 844
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From: Cape Cod Ma
My main problem is that when the cars running. Which it dosent now. It did a sort time ago. Is it missfires badly. And when it does it throws a code. And sometimes it will run great and not missfire. I brought these codes up and the ones listed are the ones it gave me. Its very wired. If i were to go out and start the car it may run fine...and it may not. It has a mind of its own. Thats why I pulled up the codes. Thanks for the replies
Team Owner
Joined: Dec 2000
Posts: 90,675
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From: SE NY
Cruise-In II Veteran
Since you have a Helms, locate the ALDL pin to which to apply +12Vdc to power the fuel pump; then check at the fuel rail to see if it's primed.
If not and the fuse is ok, pull the pump and clean the three bras contacts just under the mounting flange. These can become corroded and cause intermitent pump failure.
If not and the fuse is ok, pull the pump and clean the three bras contacts just under the mounting flange. These can become corroded and cause intermitent pump failure.
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Melting Slicks
Joined: Jun 2004
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Originally Posted by 65Z01
Since you have a Helms, locate the ALDL pin to which to apply +12Vdc to power the fuel pump; then check at the fuel rail to see if it's primed.
If not and the fuse is ok, pull the pump and clean the three bras contacts just under the mounting flange. These can become corroded and cause intermitent pump failure.
If not and the fuse is ok, pull the pump and clean the three bras contacts just under the mounting flange. These can become corroded and cause intermitent pump failure.
On an 85, a fuel pump is cheap and one of the easier projects to take on.... Sounds like it isn't holding fuel pressure...
Thread Starter
Burning Brakes
Joined: Nov 2003
Posts: 844
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From: Cape Cod Ma
I said the pumps a new ac delco...I replaced the fuell pump relay and the pump after the engine build when it was running fine. This morning I checked everything out and if jumped the pump would work.
It held fuell pressure and worked fine 35 hours ago while i was tring to fine tune the AFPR. This was before evrything else decided to take a dump. The engine was missing very badly, now it wont run.
I forgot to mention that when i took the car down to my mechanic to see if he knew of the problem why my car wasnt starting on the 1st crank of the key. He said that he hooked the car up to a scanner and the scanner didnt read anything, he double checked everything and again nothing. This was acouple weeks ago. Would this be a sing that the ecm is junk?
It held fuell pressure and worked fine 35 hours ago while i was tring to fine tune the AFPR. This was before evrything else decided to take a dump. The engine was missing very badly, now it wont run.
I forgot to mention that when i took the car down to my mechanic to see if he knew of the problem why my car wasnt starting on the 1st crank of the key. He said that he hooked the car up to a scanner and the scanner didnt read anything, he double checked everything and again nothing. This was acouple weeks ago. Would this be a sing that the ecm is junk?
