well for a while now i've had a bad MAF sensor, car running like shjt...so i know this guy who has an 86 iroc just like mine cept his in ****ty condition and undrivable, so i ask him if he will sell me his MAF. he ends up selling me his whole car for $200 bucks ( a veyr good deal considering a new MAF alone is over $260)

So i buy it and it just so happens that the engine runs perfectly its just a rusty body and a trashed tranny...so i switch out the MAF's and the car runs fantastic and the SES light goes off. so i drive it a while and then stop at the gas station to get a pop. come out start my car up and the SES light comes back on....what could the problem be? the car is still running perfect after the MAF switch...so im stumped....maybe some of the more experienced people can help me

 

Pull the codes and see what you get. Sounds like it could be a MAF burn-off relay/circuit issue (code 36 I believe).

 

Yeah it's possible that there are multiple problems and you fixed the main one. Pull the new code to verify what it is

 

I am guessing you already have done it but have you disconnected your battery oncce you installed the maf?

 

i dont have the thing that pulls the codes, i had the shop check out what the prob was when i was getting a new heatercore\blower motor and they told me it was the MAF...so i bought the dudes old iroc for $200 with a perfectly running motor (btw anyone need any parts let me know )

and btw update...today my SES light went off again...tomorrow i'll check it and if the light comes on i'll dc the battery and see what happens.

 

There is a way to check your codes with a piece of wire and your cars ALDL (I think that is the right name for it) that is located under the dash on the drivers side. Looks like a computer interface and you can strip the ends of the wire, insert them into the top two on the right hand side and turn on the ignition DO NOT START the car, just turn it to the ON position not START and the SES light will blink and you count the blinks for the codes. First you'll get a blink, pause then blink, blink for 12 about three times (maybe four) then the next series will be your trouble. You will always get a 12 when doing this, it is normal.

Anyway, if it is still MAF (code 34 I think) it is probably the MAF relay which is like $10 and it should be the relay closest to the side of the car on the drivers side firewall. Mine did the same thing you are saying, so I replaced the MAF and it still did the same thing, so it turns out I didn't need the MAF anyway, just a relay. And yes, my relay would work some and not some. Hope this helps (If you're not tired of reading by now. *L*)!

 

thanks a lot yea thats helps a ton...i'll try what you said and see what happens.

 

codes 12, 33, 34, & 36...

 

i know 34 is MAF, but what are the other 3?

 

https://www.thirdgen.org/faq/thirdgen.shtml#misc

12. No reference pulses to Electronic Control Module (ECM).
33. High voltage (low vacuum) at mass air flow sensor (or MAP sensor)
36. Burn off at mass air flow sensor OR
Problem in transmission shift OR
Fault in direct ignition system OR
Missing pulses in electronic spark timing signal

Brian

 

ok now i know the problems, how do i go about fixing them?? a friend said his moms car ran 8 codes 1 time and she fixed the first code and all of the rest of the codes were fixed by just fixing the first code. does this sound right?

 

im gonna go dc my battery quick and see what happens.

 

i dc'd the battery and now its only running codes 12 and 36, so im assuming the MAF is working properly now...how do i fix codes 12 and 36 anyone know??

 

wise man once say "change the burnoff relay"

 

BTW,you will always get a 12 dont worry about it though

 

ok cool so now im down to just a code 36, so i switch the burn off relay and that should solve the problem?? where is the burnoff relay located? maybe i could try the relay off my parts car and see what happens.

 

can someone that has experience changing one of these shed some light on it for me?

 

As far as?

 

If you open your hood it will be on the firewall on the right. it looks like this

It is the farthest to the right. There are two right next to eachother. It is about 8-9 bucks at autozone or kragens. It just has two screws holding it to the firewall. Unscrew them and plug in the new one and put it back on the firewall. Thats it. It is VERY EASY

Brian

 

ROFL..thnx a lot..i'll go to autozone tomorrow and pick one up. i'll update you when i get finished.

 

When diagnosing a MAF problem it is best to start with the relays. In the event that you replace them and they are not at fault you have not really "wasted" any money as you now have new relays which also helps eliminate culprits in the diagnostic tree.

Below is a sample location on an 86 T/A. The 2 outer relays (Power and Burnoff) are interchangable which is a good diagnostic tool. Don't quote me on these codes but for example if one is bad and you are getting a 36 then by switching the relays your code should change (to a 34 I believe). At any rate AFTER switching the relays and disconnecting battery and retesting for codes your code number will change if a relay is bad.

 

thnx for all the help guys, its cold as hell out right now so imma wait a bit before i go out and change that.

 

well....not so good news...i took the burn off relay off my parts car put it in and reset the computer, then got codes 33, 36, and 45. when i originally only had 36...now what do i do. i put the original burn off relay back on and i'll just buy a new one and see what happens? or what??