First off the car starts and runs rough. Also i hear a whistle coming from engine somewhere, maybe vaccum leak or something. I have been searching and reading up on here today. I found it has a code 34 "34. Low voltage (high vacuum) at mass air flow sensor (or MAP sensor)". I have been reading that i should start with the relays. I cant run to the parts store tonight so i took of a the mass air flow and the throttle body for a look.

I plan on cleaning them both tomorrow, and replacing the relays and the IACV.

Can some one just clarify for me how to adjust those, havent gotten that far in my search yet.

The little square of wire in the mass airflow looks to be broken, would this cause the 34 code. heres a pic


Also the back of the throttle body blades were pretty gross too.



Any help is much appreciated

 

I think you found the problem. Generally, code 34 is caused not by the MAF itself but in this case the MAF is clearly damaged. I would not even bother with the IAC or relays and go straight to replacing the MAF and cleaning the carbon off the throttle body and replacing the throttle body and upper plenum gaskets. You can get a rebuilt MAF from Autozone for about $165.

Also please list the details on your car. Year, engine, etc. Fill out your profile info.

Thanks and welcome to thirdgen.org.

 

This one is a 1987 iroc 305 TPI auto trans.

I would fill it out in my profile but its not my main one. I get a lot of these cars to fix up and make a little money and stuff.

 

i agree with burnout, that MAF is clearly damaged and probably not functioning at all. i would also take a look at the harness that plugs into that just to make sure it isn't damaged in anyway.....i had one short on me once and burnt the ground wire up from the MAF right back to the ECM

 

ill let you guys know how it all plays out tomorrow night

 

I wish my code 34 was that simple. My car has been haunted with this code since the previous owner. Receipts show 2 Maf sensors installed an ECM, relays replaced. I just replaced every gasket on the engine when it was rebuilt and the code just came back today after a year with no problem. Today I replaced every vaccum hose besides the heater controls and the pieice that goes to the resivoir in the fender which Is good because it hissed for a while when I took it off. Also did a continuity check on the wires to the ecm, ok.

Cleared the light and drove it a short distance without a problem but I know it will be back either tommorow next month or next year. I wish it would die completely so I have to find the cause and know it was fixed.