Slow 86z

86 305 tpi
well heres the story alright................
my car seems like its gotten really sluggish in the past two days and i cant figure out why. so i was bored and decided to find out why the check engine light never came on when i turned the ignition on with out starting it. (i had a feeling Somthing wasnt right, but the car has always ran well so i never really had a reason to wonder )
well i pulled the cover off and there it was no light bulb. well i pulled one out the seat belt light, and go figure it lit up about 5 seconds after i started the car.

alright long story short did the whole paper clip thing and pulled a code 34 out of it. I checked two places TGO and iroc-z.com and they both sound like it has to due with the same issue, mass air flow sensor.

TGO-----Low voltage (high vacuum) at mass air flow sensor (or MAP sensor)
or
iroc-z------Poor electrical connection, open or short in circuit; defective MAF sensor; defective ECM.

Now i have looked at a few other older posts and have read about people talking about maybe the throttle position sensor is out of adjustment. or it could also be the relay.

My question now is there any way i can narrow it down with out buying 10 different parts. or has anyone else expeinced this and how have they solved it. is there any way to test these items that they claim it might be faulty.
also im guessing that the light has probally been on since i bought it last year. i also smell fuel so im under the impression that it is running ruch.

any help would be great thanks,
Chris

aklim

Hook up scantool to see what the idle TPS voltage is. With the engine off and the key on, see what it reads when you push the pedal in slowly. It should show a gradual voltage increase. If there is a dead spot, you have a problem. I believe the TPS voltage should be around 0.54V till somewheres under 5V at WOT.

Also take out the TB and clean it throughly and also the IAC housing. Reassemble and set the IAC to about 20-30 counts and see if you get the code again.

IROC-T

As far as buying parts that aren't needed they can get expencive,but as far as relays they are cheap ($7-$15 depending where you get it)and all of them are the same,so why not keep one or even two around in case. Eventually one will go out and you'll have them.
Old Boy Scout trick : Be prepared.

Slow 86z

sorry this might sound dumb but what is a iac?
thanks Chris

Slow 86z

Wooooohooooo!!!!!!!!!!!! alright i bought 2 relays and wallaaa , it was fixed no more check engine light being on. now for another question,
how come when i still put the paper clip in to check for any error codes it still shows the code 34?

how do i reset it so it clears the code?

aklim

The code stays in there till X number of successful runs without any problem or if you disconnect the ECM fuse or battery cable for a few seconds.

lordmetalz28

what 2 relays did u buy slow 86

Slow 86z

the 2 relays that are located next to the brake booster. there is actually three relays there, but the two that have the same part # are the the ones related to the Maf sensor. one is a burn off relay and the other is MAF relay.

Chris

FruityOne

Yeah, Code 34 can often be attributed to "MAF Burn Off relay" as well. If the wiring is damaged there then it will throw the code. A bad connection up there by the relays can kill a MAF over time if the Burn-off relay isn't working as it should....


Ask me how i know......