I have a 1994 850 which keeps sputtering and stalling at stop signs and red lights and when I first sart it. While driving it runs perfecrtly. The shop told me I needed to replace the tps sensor and the mass air flow meter. He told me $550 parts and labor. Any help is greattly appreciated.

Coops

 

He is probably right. You can test the MAF to know for sure. If you unplug the MAF and start the car and it runs and drives better, it is the MAF.

Make sure you only buy the OEM (Bosch) sensors.

 

where is the MAF and how do you unplug it. If thats the problem what does it cost to repair, parts wise. does it need a software upgrade I found a dealer with to 1999 s70 and 70xc both idle like crap. the 70xc sputters, like its not firing then it fires down the line like a fire cracker dud in the engine.

 

The MAF (Mass Air Flow Sensor) is located on top of the air box between the air box and the turbo. There is an electrical connector that you can unplug and then start the car.

 

first things first, is there a check engine light?


a maf replacment is a do it your self job (i think). it is right in the open, and there is only two screws holding it in. just need to be careful with matierial handling slightly (with the new one). then i usualy do power drain on the system (dissconect battery, turn to start it for 5 seconds or so, connect battery). the power drain isnt needed, but i like to do it for good measure.


FCP is exactly right to. unplug the maf, if there is a change in idle the MAF is good. if there is no change in idle the MAF is bad.

i would be suprised if your TPS was bad, i dont see those go a whole lot on 850's....

its "possable" that you just have a bad vacume leak.


if your MAF is indeed bad go buy it from fcp and do it your self, dont let the shop charge you for two screws and 5 min of their time.

 

+1 for tony.

check those things first, and perhaps the IACv Idle Air Control valve needs a good cleaning. i had a irregular/almost stalling idle some months ago. pulled the IAC and carb cleaned the be-jeezis out of it and now the idle is smoothy-smooth

good luck!

 

last time i pulled out my IAC i forgot to plug it in before i started the car... haha. idled quite nice at 3 grand lol