MAF Sensor Unplugged ??
Homer_Homer
12-18-2005, 05:26 PM
I am troubleshooting a rough idle problem and I unplugged the MAF sensor to see if it would make a difference. It didn't and I did not get a check engine light. Is this normal?
Blackbeetle
12-20-2005, 08:04 PM
I am troubleshooting a rough idle problem and I unplugged the MAF sensor to see if it would make a difference. It didn't and I did not get a check engine light. Is this normal?
A few things
1)rev it up with the maf plugged in and unplugged and see if it makes a difference , if it does try cleaning the MAF sensor with electric contact cleaner. (go easy on the little wire , just give it a gentle burst)don't spray the stuff full force on the sensor wire , just give it enough to clean it off.
whatever you do don't use a tissue or q-tip , just the liquid.
also
2)Try unplugging the oxygen sensor - (pre cat) and see if the idle remains the same. She might be in open loop and if it stays the same the O2
sensor probably needs changing.Perhaps the sensor heater has failed.
3) check the vacuum tube on the fuel pressure regulator on the fuel
rail , if you see fuel on the vacuum side the regulator is bad.
4) don't forget to check the coil , spark plugs and wires.
5) the coolant temp sensor can also cause a rough idle.
6) this should have been the first point - check for vacuum leaks:cool:
A few things
1)rev it up with the maf plugged in and unplugged and see if it makes a difference , if it does try cleaning the MAF sensor with electric contact cleaner. (go easy on the little wire , just give it a gentle burst)don't spray the stuff full force on the sensor wire , just give it enough to clean it off.
whatever you do don't use a tissue or q-tip , just the liquid.
also
2)Try unplugging the oxygen sensor - (pre cat) and see if the idle remains the same. She might be in open loop and if it stays the same the O2
sensor probably needs changing.Perhaps the sensor heater has failed.
3) check the vacuum tube on the fuel pressure regulator on the fuel
rail , if you see fuel on the vacuum side the regulator is bad.
4) don't forget to check the coil , spark plugs and wires.
5) the coolant temp sensor can also cause a rough idle.
6) this should have been the first point - check for vacuum leaks:cool:
Blackbeetle
12-30-2005, 07:00 PM
I am troubleshooting a rough idle problem and I unplugged the MAF sensor to see if it would make a difference. It didn't and I did not get a check engine light. Is this normal?
Quote:Originally Posted by Homer_Homer
Here are a few things that I have done,
When I rev the engine it has hesitations and rough spots.
I have unplugged the MAF and revved the engine, no difference.
The exhaust smells rich.
Homer
My exhaust smelled rich as well. I went to the VW dealer today and
bought a new MAF (they call it a Air meter) which comes with the new housing , screens and sensor for 83 bucks cdn.
WOW what a difference , she runs like new.
I thought you would like to know.
Also
I found one spark plug boot that was arcing a little
Check your plug wires.
The car ran a little better after that but not a lot.
You can see it really well if you are in a dark garage.
I didn't change it , it was only a little loose ,I pushed it down onto the plug with a long screwdriver.
It was only when I changed the MAF that she started running well.
good luck
Blackbeetle
Quote:Originally Posted by Homer_Homer
Here are a few things that I have done,
When I rev the engine it has hesitations and rough spots.
I have unplugged the MAF and revved the engine, no difference.
The exhaust smells rich.
Homer
My exhaust smelled rich as well. I went to the VW dealer today and
bought a new MAF (they call it a Air meter) which comes with the new housing , screens and sensor for 83 bucks cdn.
WOW what a difference , she runs like new.
I thought you would like to know.
Also
I found one spark plug boot that was arcing a little
Check your plug wires.
The car ran a little better after that but not a lot.
You can see it really well if you are in a dark garage.
I didn't change it , it was only a little loose ,I pushed it down onto the plug with a long screwdriver.
It was only when I changed the MAF that she started running well.
good luck
Blackbeetle
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