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Roy Belding
Roy Belding, ASE Certified Technician
Category: Buick
Satisfied Customers: 5860
Experience:  Master ASE since 1980
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Need some help, 86 buick grand national v6 vin code 7, no

Customer Question

good morning
JA: Hello. What do you want help with?
Customer: need some help
JA: What is the model/year of your Buick?
Customer: 86 buick grand national v6 vin code 7
JA: Just to clarify, what's the exact code? And have you tried to reset it?
Customer: no codes car quit, has spark,,,no fuel pump relay or inj pulse also, ck eng light will not light did all wiring tests as per alldata...back probing etc... can make eng light come on by back probing circuit 419 to grd
JA: Are you fixing your vehicle yourself? What have you tried so far?
Customer: also, can ground term D of ALDL DOES have power, and bulb is good replaced ECM twice from Auto zone still suspecting faulty ecm
JA: Anything else you want the mechanic to know before I connect you?
Customer: thats about it
Submitted: 3 months ago.
Category: Buick
Expert:  Roy Belding replied 3 months ago.

Hello, my name is ***** ***** I will be glad to assist. Please allow me a moment to gather some information.

Expert:  Roy Belding replied 3 months ago.

ok, I have had many issues with re man ecms. I worked at pepboys in the past and they use the same ecms as autozone. we go to gm for the correct ones.

the only thing is that you need the original ecm, a gm unit for a core, when you get one there. they always have come through.

anyway, did you verify power to the ecm??

also, did you replace the prom as well???


Customer: replied 3 months ago.
we have an OEM core we can give to Gm, that is the unit that was in the car when it quit. at this point, i am very displeased with reman ecm's from autozone, the first one we obtained looked like a CORE itself, dirty, with raised traces on circuit board.IN all the years i was a mechanic, i also had some bad ecms from NAPA. we are using the same PROM that came with the car, it looks like an aftermarket prom, maybe a hypertec brand? i wonder if it could be the prom ? if it is bad, could this keep the ecm from turning on the check eng light even IF the ecm was ok?? all grds and power feeds seem to agree with alldata specs in troubleshooting charts. i would normally suspect a cam sensor with no injector pulse, but the check eng light keeps me from moving forward. i cannot draw any codes to go by....this car was being driven after having an alternator and battery replaced and died along the road., one more thought i had, i could not verify which wire was supposed to be the IGN 1 ( if this model has an IGN1 & IGN 2,limited wiring details for ign switch) we also replaced the ignition switch with no change. i have also checked every fusible link at the starter, all are ok. grounds at rear of right cyl head are also tight. is there anything i could be missing, before we order a GM ecm? i am working on this car for a friend, i want to be careful how i spend his money...thanks
Expert:  Roy Belding replied 3 months ago.

yep, the prom will keep the light from not coming on. try to get a new one from gm. they are still available. it is cheap enough to try with the original ecm. if that does not work then replace the ecm.


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