Question: Service engine soon light

[PAULIE B]

1987 VETTE YOU GUYS HAD THIS QUESTION BEFORE...TOOK THE VETTE OUT FOR A NICE 50 MILE RUN. ON THE WAY BACK, ON THE PKWY THE SERVICE ENGINE SOON LIGHT COMES ON. GOT HOME LET THE CAR COOL OFF HAD BREAKFAST AND CHECKED ALL FLUIDS. ALL OK. STARTED IT UP-LIGHT IS OFF. TOOK IT OUT FOR ANOTHER RIDE AND DIDN'T COME ON AGAIN. IS THERE ANYTHING I SHOULD BE CONCERNED WITH.
BTW WEDNESDAY IT'S GOING IN FOR INSPECTION AND ANNUAL SERVICE. THOUGHT BEFORE I BRING IT IN I WOULD HAVE SOMETHING TO SAY TO MY MECHANIC AND SOUND LIKE I KNOW WHAT I AM TALKING ABOUT. BTW HE HAS MANY VETTES TOO.


THANKS


DRIVE IT LIKE YOU STOLE IT!

 

[vetteboy86]

I would definitely retrieve the code and investigate.

 

[onedef92]

I would definitely retrieve the code and investigate.

Yuppers. Here's how...

Corvette C4 1984 - 1996 Electronic Control Module Recovering the Codes

 

[PAULIE B]

Yuppers. Here's how...

Corvette C4 1984 - 1996 Electronic Control Module Recovering the Codes

SHOULD I BUY A SCAN TOOL AND WHERE DO I GET ONE?:confused

 

[vetteboy86]

Don't need a scan tool. All that is required for retrieving the codes is a paper clip. With the key off connect the paper clip between terminals A and B on the ALDL connector. Turn the key to on, do not start. The service engine light will flash 12 three times, then will start flashing the codes.

You need to recognize that a code 12 is one flash, pause flash flash pause, repeated two more times. The trouble codes will flash in this same manner.

 

[boomdriver]

As others have explained, reading the codes is built in. Tuning and major diagnostics need a scan-tool. Below is a link to a scanner that seems to be what early C-4 owners would need for the OBD-1.

Equus 3140 Innova Diagnostic Code Scanner OBDI OBDII: eBay Motors (item 330456004203 end time Aug-27-10 22:49:11 PDT)

 

[PAULIE B]

WELL TOOK THE VETTE FOR THE INSPECTION AND ALL IS WELL. HOWEVER, MY MECHANIC SAID THE CODE CAME UP AND IS FOR AN ERG VALVE. HE SAID NOT TO WORRY ABOUT IT AND HE DID SAY IT IS AN EXPENSIVE PART. WHAT SHOULD I DO ? HOW DIFFICULT IS TO CHANGE OR SHOULD I JUST LEAVE IT ALONE?

THANX,
PAUL

 

[onedef92]

It's an emissions item and it is not terribly expensive. Runs about $60 bucks for your car at most auto parts stores, obviously higher at dealerships.

It's not hard to replace, (at least not on an LT1). Fix it yourself and save the labor cost. They typically fail due to the diaphragm on the valve deteriorating from engine heat, resulting in a vacuum leak and Code 32 popping up on your DIC.

 

[boomdriver]

It's an emissions item and it is not terribly expensive. Runs about $60 bucks for your car at most auto parts stores, obviously higher at dealerships.

It's not hard to replace, (at least not on an LT1). Fix it yourself and save the labor cost. They typically fail due to the diaphragm on the valve deteriorating from engine heat, resulting in a vacuum leak and Code 32 popping up on your DIC.

I think I paid about $75 for mine and had it done in less than 2 hrs. Hardest part is having the right tools for the EGR mounting bolts for a L-98. One side takes a socket and the other needs an offset wrench, I think it was...not a real big deal but inconvenient if you have to stop and go buy a tool in the middle of the work. Have some carb cleaner for the egr ports. Lots of "how to" stuff posted on doing this.
You DO want to test the EGR valve before changing. Often its just a broken vac line between the egr and the egr solenoid.