Mass Air Flow sensor problem
 

Hi,
I'm new to the forum and the Bonneville - my Aunt gave it to me when she moved into a nursing home. It has 107K miles and is stumbling at idle and when accelerating. It runs ok once it gets going. I got the error code - 34 - MAF Sensor-voltage too low (thanks to a posting on this forum!), and am wondering if this is enough to cause the stumbling. I was thinking it could be a fuel pump issue as well, but changing this would be much easier than changing the fuel pump.

Any suggestions or other ideas would be greatly appreciated!!

Thanks!
Tom

Well, stumbling at idle.. this sounds like you have an erratic idle, but not an idle which goes from 900 to 1200 rpm instantly, correct? This could be several things.. but they all have to do with data the MAF sensor reads. The thing that gave mine the erratic idle, is when I removed the MAF screen. It is located right after the accordian tube to the MAF body. It takes just a minute and a screwdriver. If there is a honey comb type thing in there [and doesn't appear too damaged] then chances are your MAF sensor is giving poor data. Try unplugging the MAF sensor plug [black rectangle located on MAF sensor body, with a three wire plug on it]. It will set a code, don't worry about that, but see if that fixes the idle.

Also, before Bill hounds you for not having your year and trim model in your sig, i'll politely ask you t do so ;).


-justin

Dirty TB and IAC passage. In addition to a possible dirty MAF.

I belive the dirty TB causes a high idle, and IAC causes a drunken slosh of an idle. MAF sensor could be at fault.. which I believing is the fault in this situation.


-justin

Yeah man its really easy and fairly quick just to pull the TB, yank all the sensors and clean everything up. It'll probably feel like a new car. Get a bottle of carb cleaner and a bottle of electrical/sensor cleaner. With $5 and ~20min your car will feel much better.

Bill is going to disagree with you on the carb cleaner.. ;). Just be careful with the removal, my car is especially prone to breaking, and anything plastic that can break, has broken. The throttle body doesn't have too much as far as plastic goes.. but there are some clips on there.. that if they are handled rough, will break.


-justin

No carb cleaner? Why?

I'll second this question.

carb cleaner made for an effective bug spray for ants in my backyard, lol

Bill and I went at it.. here.


-justin

If any residue remains in the MAF passage after cleaning, it can wipe out your MAF sensor. Also, some guys like to spray it in. Bad news for plastic intakes.

If done CAREFULLY, it can be used, but it's much simpler to just simply explain that it shouldn't be used. Intake-safe cleaner is just as effective, and doesn't have the same dangers to your sensors and such as Carb cleaner.