I don't know what's wrong with my car. Recently it lost a lot of power. It misses and cracks. We replaced the: mass air flow sensor, coil pack, we put in new spark plugs and spark plug wires in it.
If you unhook the mass airflow
sensor it runs smother but not as
usual. If it's hooked up it's missed
very bad. Going into gears it shakes
like crazy until you get over 3500
rpms. It can barley pull it's self
the sensor tells the computer what to do, bad sensor=bad input while no sensor=no input and computer goes into a kind of default mode which lets the car run but not efficiently. You pretty much have pinned down the problem area and now you need to see if sensor is just blown or is it detecting a problem that needs correcting.
Ie; new sensor could be defective ( ever screwed in a brand new light bulb and had it blow as you were screwing it in?) but more likely the air filter is your culprit.
Not necessarily the sensor is damaged maybe the problem has to do with fuel mixture which is affected by this sensor, check the fuel pressure to see if it is correct and read the codes also to look for more clues. In a live data capable equipment you can see the measure of the sensor to determine if it is the problem. I personally don't think it is...
one always hopes that it is just a bad sensor because if it is okay then that means that something has been detected that the PCM doesn't like. The air flow can be restricted due to clogged up air intake, it can be affected by a leak in the intake,it can be affected by a misfire that temporarily reverses the air flow. You hope for the best and work your way towards the worst.
Looking for a Used Golf in your area?
CarGurus has 2,801 nationwide Golf listings starting at $1,995.
Search Volkswagen Golf Questions
Are you a UK consumer? CarGurus now has a discussion forum in the UK.
Volkswagen Golf Experts