Logan Bryant

When I start it, it won't want to idle. It will want to bog down. I will unplug the maf sensor and the idle will go up to about 800-900 rpm. Also when I go and drive it, with the sensor out, it will want to bog down while trying to get on the gas. Once it reaches about 200F it will run right. I just changed the fuel filter and nothing changed. The only thing I want to know is if I should try and clean the maf, or just replace it.

TylerSteez

iTrader: (3)

No check engine light? You can try and clean the maf with maf cleaner before shelling out the $$$ for a re manufactured one but I wouldn't get my hopes up on it.

vinny R

Does it act the same with the sensor plugged in? at 200 does it run right?
I had a problem with my ECM not coming out of start mode. I would have to wait until the temp came up and had to shut the car off and start it up again. This would restart in normal operation as the temp would be up. I would not get a Check Engine light as start mode is a normal operation. I don't think the MAF sensor is your problem, There is a Idle Air Control sensor that does get crappy, you may want to clean that one also.

Logan Bryant

The check engine light has always been on due to having headers and not putting the o2 sensor back on. Once it reaches 200F it I'll run perfect. No bog or anything.

TylerSteez

iTrader: (3)

thats your problem

mcquigg

The O2 sensor needs to be hooked up. The ECM relies on the MAF and O2 input to operate the motor effectively.

Steve Mack

iTrader: (5)

Dude the O2 sensor is your main controller for your fuel system.

SbFormula

I find it interesting that your set up can work without an 02 sensor hooked. It is beyond my understanding! Your AFR must be inaccurate because your ECM can not correct the AFR under normal cruise and idle. In WOT and open loop it won't matter but in normal drive you can be too rich or too lean which will have consequences on your spark plugs, engine temperature and cat converter.


Regards

Logan Bryant

So.... Went and looked at the headers again and found the o2 sensor down by the collector. The owner told me that is why the check engine light was on, when I bought it. So I guess it leaves one thing left....

Logan Bryant

I checked the codes and i got a code 34, and I also changed to toast new Bosch maf sensor.

mcquigg

If your still getting code 34 after the MAF was changed it may be the burn-off relay, 85 was the last year GM used the combined power/burn-off unit.