Rough Idle, Engine hesitation..?
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Joined: Jun 2008
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From: Llandudno, Cape Town, South Africa
late 2009 CLK 350 Coupe Elegance, '65 Jaguar S Type wires
First signs of a bad O2 sensor are engine stumble on acceleration.
Air leak in any vacuum pipe or the Captive crankcase ventilation system should cause the vehicle to run lean. If it can't compensate sufficiently it should throw a fuel trim code.
I would replace all plug wires first.
Air leak in any vacuum pipe or the Captive crankcase ventilation system should cause the vehicle to run lean. If it can't compensate sufficiently it should throw a fuel trim code.
I would replace all plug wires first.
Thread Starter
Senior Member
Joined: Jul 2008
Posts: 420
Likes: 2
From: Nor Cal
A Car
updated codes this morning:
P2001- Random Misfire
P2052- Misfire cylinder 5
P2054- Misfire cylinder 2
P2056- Misfire cylinder 3
P2082- Left O2 Sensor Short Circuit
Im switching out the wires as i am typing this. lol
P2001- Random Misfire
P2052- Misfire cylinder 5
P2054- Misfire cylinder 2
P2056- Misfire cylinder 3
P2082- Left O2 Sensor Short Circuit
Im switching out the wires as i am typing this. lol
Super Moderator
Joined: Jun 2008
Posts: 19,942
Likes: 192
From: Llandudno, Cape Town, South Africa
late 2009 CLK 350 Coupe Elegance, '65 Jaguar S Type wires
This is all looking plain now. Replace both upstream O2 sensors & all wires to start with. Pray the coils are OK.
Thread Starter
Senior Member
Joined: Jul 2008
Posts: 420
Likes: 2
From: Nor Cal
A Car
Ah, finally. Just finished up changing the wires in all cylinders. Ran smooth for a bit, then engine started to stumble after 5 mins of driving. Went back and inspected and cleaned all plugs/wires again, clean the throttle body, MAF, and air filters. Started her up and she was running normal.
Drove for a bit longer and bam, no signs of misfire or hesitation.
During idle, in gear, or under WOT... she ran smooth as butter. (not to mention i feel it running a lot stronger too)
Let the good times roll, gentlemen.
Drove for a bit longer and bam, no signs of misfire or hesitation.
During idle, in gear, or under WOT... she ran smooth as butter. (not to mention i feel it running a lot stronger too)
Let the good times roll, gentlemen.
Newbie
Joined: Apr 2018
Posts: 1
Likes: 0
C180 Kompressor
Was due to exhaust!
my C180 would shut down cylinder 3 when idle, fine if you kept revs up. Back to normal when ignition turned off and back on. It turned out to be a leaking exhaust! New exhaust, problem solved.
Newbie
Joined: Apr 2007
Posts: 3
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Idles fine in neutral or park, rough when in drive, fuel pressure low?
My 2003 c240 4matic Idles fine in neutral or park, rough when in drive, especially when steering wheel is off center. Throttle body is clean. new plugs, wires, no vacuum leaks, new motor mounts, new fuel filter. Fuel injectors were cleaned. No codes either.
Only issue I can see is fuel pressure is at 51 maybe 52 PSI not at 55 when starting or idling, does not change when reving engine. Is this too low? I think it should be 55 but I am not sure if this is enough to affect it.
Any comments?
Only issue I can see is fuel pressure is at 51 maybe 52 PSI not at 55 when starting or idling, does not change when reving engine. Is this too low? I think it should be 55 but I am not sure if this is enough to affect it.
Any comments?
Last edited by nmpaulcp; May 26, 2018 at 11:04 AM. Reason: Incorrect spelling
