CHECK ENGINE LIGHT Codes P0302 P0172
08-25-2011 | 11:06 PM
#1
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05 c230k 6spd
CHECK ENGINE LIGHT Codes P0302 P0172
I hate posting these threads but I need help since I failed emissions due to this stupid check engine light.
When I started the car up in the morning, right away I could notice a rougher idle and the car seemed to be shaking and the check engine light went on right away. I drove the car and it smoothed out and car drove like normal and idled normal too. I had the codes pulled and P0302 P0172 came up, I figured it was no big deal and erased them since car ran fine.
Today they came back when I started the car again. What could it be? Maybe crappy gas? Should I add some Techron or SeaFoam? Maybe condensation in the fuel?
BTW I have 72k miles on the car, fuel filter was done few months ago, sparks plugs done before summer, MAF was cleaned as well, oil change not too long ago either, and the air filter was replaced same time as oil change. Car runs fine other than this and had no rough idle prior to this.
When I started the car up in the morning, right away I could notice a rougher idle and the car seemed to be shaking and the check engine light went on right away. I drove the car and it smoothed out and car drove like normal and idled normal too. I had the codes pulled and P0302 P0172 came up, I figured it was no big deal and erased them since car ran fine.
Today they came back when I started the car again. What could it be? Maybe crappy gas? Should I add some Techron or SeaFoam? Maybe condensation in the fuel?
BTW I have 72k miles on the car, fuel filter was done few months ago, sparks plugs done before summer, MAF was cleaned as well, oil change not too long ago either, and the air filter was replaced same time as oil change. Car runs fine other than this and had no rough idle prior to this.
08-26-2011 | 03:58 PM
#2
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From: Llandudno, Cape Town, South Africa
late 2009 CLK 350 Coupe Elegance, '65 Jaguar S Type wires
P0172 = System too Rich (Bank 1)
P0302 = Cylinder 2 Misfire Detected
Clean the MAF again. Check plug on cylinder 2 as well as coil. At 72K your O2 sensors s/b OK.
P0302 = Cylinder 2 Misfire Detected
Clean the MAF again. Check plug on cylinder 2 as well as coil. At 72K your O2 sensors s/b OK.
08-26-2011 | 10:32 PM
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05 c230k 6spd
Ok the check engine light went away by itself after a few drive cycles... Could it have been the gas? I have about less than 1/4 of a tank left, Im gonna fill up at a different station after the light goes on. Would it be safe to get it tested for emmissions now or should I wait a few days to make sure it doesn't come back?
08-27-2011 | 09:56 AM
#4
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From: Llandudno, Cape Town, South Africa
late 2009 CLK 350 Coupe Elegance, '65 Jaguar S Type wires
You need to run about 100 miles of normal use for everything to reset itself or they will pick it up at the emissions check.
It could be caused by many things.
It could be caused by many things.
. Thanks Glyn
09-03-2011 | 02:22 AM
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05 c230k 6spd
Ah damn it the car got worse, the check engine light went away by itself and came back again. Tonight it ran really rough and I had to drive it home like 10 miles. It sounded like a boxer sti engine or something, like it had that rumble and I could feel the car shake a bit. I have not had a chance to read the codes but I assume they will be same like last time, misfires and stuff. Ill try to get the codes and update. But does anyone have any idea what this could be?
