Up Date (Cross Fire Help)
Thread Starter
Racer
Joined: Oct 2003
Posts: 376
Likes: 0
From: NE PA PA
Up Date (Cross Fire Help)
A friends 82 won't start. New fuel pump-new EST in dist.-new ECM (computer) - new prom chip in computer. Voltage at injector coil is good. Will not cycle. Note-- check engine lite does not come on when key is turned. :banghead:
Race Director
Joined: Dec 1999
Posts: 16,945
Likes: 9
Re: Up Date (JBR)
the ECM is new? Weird
Does the fuel pump run? (it runs for a few secs, but when you don't crank it goes off again, when cranking it comes back on) The CEL might just be burnt out. Check that. Read out the ECM (scanner) and look if the ECM actually sees a rpm/cranking signal. Maybe the wiring is messed up somewhere.
Is the prom installed correctly? There's a tab that has to line up with a notch in the carrier, if the other way around the prom is junk and will get very hot.
[Modified by Twin_Turbo, 7:28 AM 1/12/2004]
Does the fuel pump run? (it runs for a few secs, but when you don't crank it goes off again, when cranking it comes back on) The CEL might just be burnt out. Check that. Read out the ECM (scanner) and look if the ECM actually sees a rpm/cranking signal. Maybe the wiring is messed up somewhere.
Is the prom installed correctly? There's a tab that has to line up with a notch in the carrier, if the other way around the prom is junk and will get very hot.
[Modified by Twin_Turbo, 7:28 AM 1/12/2004]
Thread Starter
Racer
Joined: Oct 2003
Posts: 376
Likes: 0
From: NE PA PA
Re: Up Date (JBR)
Thanks Twin_Turbo. Yes the ECM is new.
Per my friend the prom chip carrier can only go in one way,might be wrong.
Also he will check if the CEL is burnt out.
One other piece of info. The fuel pump only runs when cranking. Which this seems strange, I thought it should run shortly when the key is in the on position, to build pressure then shut off. :cheers:
Per my friend the prom chip carrier can only go in one way,might be wrong.
Also he will check if the CEL is burnt out.
One other piece of info. The fuel pump only runs when cranking. Which this seems strange, I thought it should run shortly when the key is in the on position, to build pressure then shut off. :cheers:
Race Director
Joined: Dec 1999
Posts: 16,945
Likes: 9
Re: Up Date (JBR)
yes, have someone listen at the rear, when the key is in the on pos. the pump should run for 4-6 or so seconds, then shut down and come back on when cranking.
the prom carrier only goes in 1 way yes but it's perfectly possible to position the prom in the carrier the wrong way around.
the prom carrier only goes in 1 way yes but it's perfectly possible to position the prom in the carrier the wrong way around.
Thread Starter
Racer
Joined: Oct 2003
Posts: 376
Likes: 0
From: NE PA PA
Re: Up Date (Twin_Turbo)
We have listened for the pump to turn on at the tank. with switch in the on pos. It will not . It only turns on when cranking. The prom chip is in the carrier from the factory and has not been removed from that position. How can one tell if it is in the wrong pos. in the carrier, from the factory :confused:
Race Director
Joined: Dec 1999
Posts: 16,945
Likes: 9
Re: Up Date (JBR)
as I said, the carrier has a notch and so does the prom, the 2 have to line up.
But, the problem is probably not the prom. It sounds as if something is cutting off the pump, it's either a bad relay, bad wiring or maube the oil pressure sender.
But, the problem is probably not the prom. It sounds as if something is cutting off the pump, it's either a bad relay, bad wiring or maube the oil pressure sender.
Racer
Joined: Nov 2002
Posts: 364
Likes: 0
From: Potomac MD
Re: Up Date (JBR)
JBR, is there a middle metal contact in your new distributor cap from the coil where the three wires connect to distributor? I was missing the middle ground. Also check water temp sensor.
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