Service Engine Soon Light of DOOM

I own a 2.8L 89 firebird and recently the SES light goes on and there is a loss of power (i have to be in 5th to get it up to 50 km/h. The weird thing is that it goes off and on randomly and whenever it is off it runs normally. I took it to a local shop to run it on the computer and they said they couldn't get it to set off.

Any suggestions would be greatly appreciated...

Oh and i want to get it painted....Any suggestions would be great

might be the smog pump, most likely.

What do you mean by set off?. Do you mean they couldn't read it or couldn't get it to flash codes?. The process to reading codes on OBD 1 early systems is quite simple.

Turn ignition switch to OFF position
Locate Data Link Connector (DLC), see image below.
Jumper the A&B terminals(a paper clip or a jumper wire work ok)
Turn Ignition switch to ON position.
Count the flashes on the "CHECK ENGINE" or "SERVICE ENGINE" light.
FLASH, pause, FLASH, FLASH = code 12

http://www.troublecodes.net/gmobd.gif

Hi FormulaLT1,

It blinked once, paused, then blinked twice, then repeated itself. So you were right, it is code 12...what does that mean?

It's a good thing they didn't charge me anything

Thanks

Code twelve is just a check code that means the ECM is functioning properly. Did it flash any code after it flashed code 12 three times?. If so, whatever number that was. That is the code you had in the computers memory.

It read Code 42

A website said it's a Bypass or EST problem

http://iroczone.com/specs/ECMTroubleFBody.htm

Its a ignition module code. You need to check the connection on that and then most likely replace it.

Thanks for all your help Formula

No problem. Good luck

John

i need help... i just got the SES light this morning..and i did the jumper, i saw the 1:2, 1:2, 1:2 and then it flashes 3:6 ?!!? is this a special case? whats up with this.. after it flashes 3:6 three times, it goes back to 1:2, 3 times, then back to 36...whats an error 36?!?! is my car screwing with me?!

its a 1988 5.7L TPI WS6 formula..

Thats a MAF code. Check the connections to the MAF and if those check out. Then your going to check the MAF itself.

ohh, thanks! i have a spare MAF..it came w. the car so maybe ill try swap it and see..

hey LT1! thanks :) i finally changed the MAF and the code wouldnt go away..so i was pretty bummed cuz i thought i had to buy another one...

after tonight tho, it worked! wooo. :)

a code is stored in the ecm memory til the ECM is reset , either via disconneting the battery for 10 minutes or via a scan tool. Glad it worked though.

Hi it's me again Formula,

I replaced the ignition module but the light still comes on randomly... could it be the ECM itself, glitching. Also i did the test again and it read 32, then i turned it off then did it again. It didn't do code 12, but went to code 42 again.

Huh, you should test the signal coming into the ICM. It may be a wiring problem but it could also be the ecm as well.