MAS replaced........car still idles a bit rough, what could it be?
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From: Saytown
2000 C280 Sport
MAS replaced........car still idles a bit rough, what could it be?
I just noticed my car idles a bit rough (misses) after the check engine light informed me of a bad MAS, which I had replaced. Got my car back, and it still idles rough........rougher than it did before the check engine light appeared. What could it possibly be?
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From: Boston
'05 A4 1.8TQM6
bad/rough idle could be O2 sensor as well. I had a idle that shook the car at times at stop lights...dealer diagnosed to a O2 sensor, but it didn't throw any codes. Probably starting to go bad. After it was replaced, idle was much better.
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From: Saytown
2000 C280 Sport
Took my car in this morning.........service manager believes the idle is set too low on my car.......when he rev'd the engine up just a teeny bit, it smoothed out. My idle is down around 500-700 rpm and it need to be around 1000 I believe.
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From: Boston
'05 A4 1.8TQM6
Originally posted by lebomb
Took my car in this morning.........service manager believes the idle is set too low on my car.......when he rev'd the engine up just a teeny bit, it smoothed out. My idle is down around 500-700 rpm and it need to be around 1000 I believe.
Took my car in this morning.........service manager believes the idle is set too low on my car.......when he rev'd the engine up just a teeny bit, it smoothed out. My idle is down around 500-700 rpm and it need to be around 1000 I believe.
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From: Boston
'05 A4 1.8TQM6
Originally posted by lebomb
It actually idles around 500 and they are gonna bump it to about 700.
It actually idles around 500 and they are gonna bump it to about 700.
Atleast your's isn't the case
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Did you clean out your throttle body? I did that to my car and it boosted the RPM up a bit. Actually its a bit over 10 when i start it and when i am driving and at a stop its about 7-800. Worked out a lot better than 500. Now i just need the 02 sensors replaced and my MAS= $$$$
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From: San Diego
1995 C280
i just got my car back a week ago because it was surging (rpm's up & down) around 500 to 1000rpm. parking lot speeds. it turned out to be an air leaky hose somewhere in the transmission. car runs better than ever now.
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From: Milton/Westport, MA USA
me: 2015 SL400 & 2015 ML400; wife: 2022 GLC Coupe; daughter: 2017 GLC SUV
lebomb, what did that MAS replacement cost you (I assume you went to a dealer)? I just bought one on ebay for $40 and I'm hoping that's MY problem as well. and GDawg, did you have the O2 sensor done at the dealer (Hatch)? with all the DIY stuff you do, I'd be surprised.....
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From: Boston
'05 A4 1.8TQM6
Originally Posted by eddieo45
lebomb, what did that MAS replacement cost you (I assume you went to a dealer)? I just bought one on ebay for $40 and I'm hoping that's MY problem as well. and GDawg, did you have the O2 sensor done at the dealer (Hatch)? with all the DIY stuff you do, I'd be surprised.....
haha, yeah, I had the O2 sensor done at a dealer (before I knew about hatch) and it was $210. It was done at Foreign Motors West in Natick.
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From: Boston
'05 A4 1.8TQM6
Originally Posted by mufeed
Where is the 02 sensor located on a 1999 c280, does anyone know?
Do a quick search in the w202 forum and there are a few posts on this I believe from a while back
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From: Milton/Westport, MA USA
me: 2015 SL400 & 2015 ML400; wife: 2022 GLC Coupe; daughter: 2017 GLC SUV
$210 doesn't sound bad for Foreign Motors! I search for MAF's all the time, and I was the only bidder on this one. When you changed yours, were there any other adjustments necessary (I think it was blackmercedes who told me that when the CEL goes on, the fuel trim setting changes, and it has to be reset with the new MAF)?
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From: Boston
'05 A4 1.8TQM6
Originally Posted by eddieo45
$210 doesn't sound bad for Foreign Motors! I search for MAF's all the time, and I was the only bidder on this one. When you changed yours, were there any other adjustments necessary (I think it was blackmercedes who told me that when the CEL goes on, the fuel trim setting changes, and it has to be reset with the new MAF)?
