Rough Idle
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1967 Morris Cooper "S", 1983 911SC, 1997 Toyota Tacoma, 1999 HD FXSTB, 1998 C43
Rough Idle
Need some ideas for rough idle - NO codes, plugs are new I'm trying to avoid a trip to the $tealership. Car has 140K on the odo and is fastidiously maintained... Fuel injector clean up, coil pack issue, rrrelp!
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1967 Morris Cooper "S", 1983 911SC, 1997 Toyota Tacoma, 1999 HD FXSTB, 1998 C43
Wires are less than a year and plugs are new - you think the Oxygen sensor may be culprit? They have not been changed...
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1995 C36 AMG, 1998 C43 AMG
How new are the plugs? Seems like I've read all too many times on here something like this with new plugs or sensors or wires and the new parts were the culprit. Try some different/the old plugs maybe?
#6
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O2 sensors are used at idle and they are a normal wear part (and at 10+ years, they should be dead), so they are a prime suspect. When dying, they either produce low voltage and cause the engine to run rich, or they get coated so bad that they can't detect O2 and cause the engine to run lean (in search of more oxygen).
If you have a friend at a smog shop, ask them to check whether it's rich at idle. You don't need the whole smog test, just idle. It should take about two minutes. If it's rich, my guess is it's the sensors. If it's lean, go home, pull the sensors (after it's cooled down), clean them and retest.
If you have a friend at a smog shop, ask them to check whether it's rich at idle. You don't need the whole smog test, just idle. It should take about two minutes. If it's rich, my guess is it's the sensors. If it's lean, go home, pull the sensors (after it's cooled down), clean them and retest.
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#8
do you notice any jerkiness from your transmission?
if your o2 sensor is bad, you'll have jerky shifting between 1st and 2nd gear in D-mode if you make a fast start from stand still with your C43.
2nd gear wont engage, you'll have to let go off the accelerator lose speed and then 2nd gear will engage.
I had this prob on my car but us europeans don't have the CEL on our clusters therefore it was difficult to know what the prob was without a codereader.
try your car in D-mode from standstill and see if your transmission is acting strange
if your o2 sensor is bad, you'll have jerky shifting between 1st and 2nd gear in D-mode if you make a fast start from stand still with your C43.
2nd gear wont engage, you'll have to let go off the accelerator lose speed and then 2nd gear will engage.
I had this prob on my car but us europeans don't have the CEL on our clusters therefore it was difficult to know what the prob was without a codereader.
try your car in D-mode from standstill and see if your transmission is acting strange
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1967 Morris Cooper "S", 1983 911SC, 1997 Toyota Tacoma, 1999 HD FXSTB, 1998 C43
C43AMG - how goes it! Check your PM.
Marcus, I ordered 02 sensors all around and new MAF. Always appreciate your input. I will apprise progress...and Kowalski yes, sometimes on the symptoms you describe. We'll see what happens once I replace the parts...
Thanks for the help guys!
Marcus, I ordered 02 sensors all around and new MAF. Always appreciate your input. I will apprise progress...and Kowalski yes, sometimes on the symptoms you describe. We'll see what happens once I replace the parts...
Thanks for the help guys!
#11
C43AMG - how goes it! Check your PM.
Marcus, I ordered 02 sensors all around and new MAF. Always appreciate your input. I will apprise progress...and Kowalski yes, sometimes on the symptoms you describe. We'll see what happens once I replace the parts...
Thanks for the help guys!
Marcus, I ordered 02 sensors all around and new MAF. Always appreciate your input. I will apprise progress...and Kowalski yes, sometimes on the symptoms you describe. We'll see what happens once I replace the parts...
Thanks for the help guys!
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1967 Morris Cooper "S", 1983 911SC, 1997 Toyota Tacoma, 1999 HD FXSTB, 1998 C43
Dunno if I'm looking forward to removing those sensors, but I am looking forward to curing this rough idle This car is hardly abused by any stretch of the word.
#13
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On a CLK, they look tougher than they really are. The driver's side front is the toughest. That one is done from underneath. The passenger side front is the easiest and is accessed from under the hood. The two secondary sensors are both accessed from underneath, but are both very easy. On an ME 2.8 car (2001 and later), each sensor has a unique plug, so they can’t be mixed up. The plugs may be different on an earlier system.
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1967 Morris Cooper "S", 1983 911SC, 1997 Toyota Tacoma, 1999 HD FXSTB, 1998 C43
FOLLOW UP
Many thanks to all - esp. MarcusF and Kowalski! The car runs great It was an 'unfun' job. Car idles great and you're right Kowalki, the shift from 1st to 2nd is much smoother...I also replaced the MAF.
Pics of the 02 sensors below...I'm sure you can pick out the ones closest to the manifold, or pre-cat.
Uploaded with ImageShack.us
Pics of the 02 sensors below...I'm sure you can pick out the ones closest to the manifold, or pre-cat.
Uploaded with ImageShack.us
Last edited by StapleGun; 12-03-2011 at 11:58 AM.
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00 C200 & 00 C55 & 06 SLK55
Many thanks to all - esp. MarcusF and Kowalski! The car runs great It was an 'unfun' job. Car idles great and you're right Kowalki, the shift from 1st to 2nd is much smoother...I also replaced the MAF.
Pics of the 02 sensors below...I'm sure you can pick out the ones closest to the manifold, or pre-cat.
Uploaded with ImageShack.us
Pics of the 02 sensors below...I'm sure you can pick out the ones closest to the manifold, or pre-cat.
Uploaded with ImageShack.us
brought the car from Japan 3 years ago.......
ZAYED,,
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1967 Morris Cooper "S", 1983 911SC, 1997 Toyota Tacoma, 1999 HD FXSTB, 1998 C43
cm60k - maybe a Euro market?
Don't know what you have be a US Spec or otherwise since you're in UAE - all I know is you will spend some time removing the driver's side unit. I purchased a KD Tool 02 Sensor kit from Amazon for $40, it had all the sockets I needed.
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Where did you buy the sensors? Part number?
Many thanks to all - esp. MarcusF and Kowalski! The car runs great It was an 'unfun' job. Car idles great and you're right Kowalki, the shift from 1st to 2nd is much smoother...I also replaced the MAF.
Pics of the 02 sensors below...I'm sure you can pick out the ones closest to the manifold, or pre-cat.
Uploaded with ImageShack.us
Pics of the 02 sensors below...I'm sure you can pick out the ones closest to the manifold, or pre-cat.
Uploaded with ImageShack.us