Washed Engine (Carefully!) - Now misfires...
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From: America
1999 C43 AMG, 2005 E55 Wagon
Washed Engine (Carefully!) - Now misfires...
I bought Kent Bergsma's video on how to carefully wash your m113 engine and followed his advice to the letter. I didn't have an air compressor, so my drying method consisted of using a shop vac as best as I could to vacuum any standing water and dry the engine as best as I could. Then, I let it sit for 2 days to dry, just to be safe.
Tried to start her up just now and she ran like **** for a minute, but then seemed to be just fine. Not that uncommon for an engine that was just washed.
After it seemed to be idling normally, I drove off. But I noticed it was a little sluggish, so gave it a little more throttle, maybe half throttle. It bogged, hesitated, triggered a CEL, and then went into limp mode.
Got it home, pulled codes:
Misfire cylinder 5, cylinder 7, random misfire, O2 bank 1 sensor 2 failure on both heater and circuit.
I let it warm up to idle, thinking maybe it needs a good heat cycle to really dry out. Cleared codes.
Cranked up just fine, smooth as always. But I noticed the misfire would return if I tried to rev it. If I slowly revved, the misfire would not show up.
Tried to drive away again, same thing, except now it's throwing a code for cylinder 5 and 6 (not 7) as well as random/multiple misfire detected. No code for O2 sensor this time (it's a relatively new sensor, surely the code was hitting it due to it being cold and having a misfire).
I used a spray bottle of 100% purple power to gently soak engine. Allowed to sit for a few minutes, making sure it didn't dry. Then scrubbed with plastic brushes as well as a small paint brush. Used a very gentle setting water spray to rinse clean. Repeated this 1 time due to an excessively soiled engine (290k miles!).
Now, misfire. Help?
Tried to start her up just now and she ran like **** for a minute, but then seemed to be just fine. Not that uncommon for an engine that was just washed.
After it seemed to be idling normally, I drove off. But I noticed it was a little sluggish, so gave it a little more throttle, maybe half throttle. It bogged, hesitated, triggered a CEL, and then went into limp mode.
Got it home, pulled codes:
Misfire cylinder 5, cylinder 7, random misfire, O2 bank 1 sensor 2 failure on both heater and circuit.
I let it warm up to idle, thinking maybe it needs a good heat cycle to really dry out. Cleared codes.
Cranked up just fine, smooth as always. But I noticed the misfire would return if I tried to rev it. If I slowly revved, the misfire would not show up.
Tried to drive away again, same thing, except now it's throwing a code for cylinder 5 and 6 (not 7) as well as random/multiple misfire detected. No code for O2 sensor this time (it's a relatively new sensor, surely the code was hitting it due to it being cold and having a misfire).
I used a spray bottle of 100% purple power to gently soak engine. Allowed to sit for a few minutes, making sure it didn't dry. Then scrubbed with plastic brushes as well as a small paint brush. Used a very gentle setting water spray to rinse clean. Repeated this 1 time due to an excessively soiled engine (290k miles!).
Now, misfire. Help?
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did you wash your engine when it was hot?
did you drive your car before you washed your engine?
that's not a good thing to do.
do you have a compressor with a long hose and pistolgrip spraynozzle, try to blow away the water around your sparkplugs and electronics with air pressure.
that might help?
something is soaked up on your engine.
drive around and warm up your car
did you drive your car before you washed your engine?
that's not a good thing to do.
do you have a compressor with a long hose and pistolgrip spraynozzle, try to blow away the water around your sparkplugs and electronics with air pressure.
that might help?
something is soaked up on your engine.
drive around and warm up your car
Last edited by KJI3jflarryfe93; Apr 28, 2015 at 07:39 AM.
Thread Starter
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From: America
1999 C43 AMG, 2005 E55 Wagon
Well, I did let it warm up to 80C to build up some heat, thinking it needed a good heat cycle to completely dry out, but that didn't help. Maybe I didn't give it enough time to dry completely.
This morning it started right up but had the misfire when I tried to rev. I let it sit and idle for 5 minutes and when I came back it was fine. Took it for a short drive down the street and it seemed completely fine. I'll check it again this afternoon.
This morning it started right up but had the misfire when I tried to rev. I let it sit and idle for 5 minutes and when I came back it was fine. Took it for a short drive down the street and it seemed completely fine. I'll check it again this afternoon.
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From: America
1999 C43 AMG, 2005 E55 Wagon
It seems completely fine now. Guess a few heat cycles cleared the issue up. Must have still been wet somewhere. Ran fine yesterday, so I went for a drive. Some punk in a white integra type R with fart cannon kept trying to push me into a race. I finally gave in and did a full throttle run from about 5mph start. Absolutely humiliated him. After that he backed off and avoided me until I turned off 
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From: north jersey
99 c43,90 mustang gt supercharged convertible,07 acura tl type s, Hummer H3t pickup
It seems completely fine now. Guess a few heat cycles cleared the issue up. Must have still been wet somewhere. Ran fine yesterday, so I went for a drive. Some punk in a white integra type R with fart cannon kept trying to push me into a race. I finally gave in and did a full throttle run from about 5mph start. Absolutely humiliated him. After that he backed off and avoided me until I turned off
fart cannon 
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98 C43, 15 Alfa 4C LE, 18 Tesla Model 3 DM Perf, 08 Duc S1000, 02 Duc 998, 98 Duc 748, 01 Miata
Probably still just had some residual water down in the spark plug area that was causing the misfire. Glad to see it has worked itself out.
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From: America
1999 C43 AMG, 2005 E55 Wagon
Yeah, long story.
Some guys were talking about how to properly wash a mercedes engine. I chime in and warn them to never use a pressure washer and get met with 2 or 3 of them nearly spitting in my face. "WHAT ARE YOU TALKING ABOUT I DO IT ALL THE TIME ON MY CUSTOMER'S CARS NEVER HAD AN ISSUE"
Blah blah blah. I warn them that it's absolutely not a good idea despite how many times they may have gotten away with it. They don't believe me, think I'm making **** up and don't know anything about cars, challenge me to find any kind of expert that agrees with me.
So, I go to Kent's site at mercedessource.com and buy his $5 video on demand about how to properly wash a modern MB engine, and he uses an E430 to demonstrate. He twice says "DO NOT STICK A PRESSURE WASHER UNDER HERE" and it shuts them up.
Some guys were talking about how to properly wash a mercedes engine. I chime in and warn them to never use a pressure washer and get met with 2 or 3 of them nearly spitting in my face. "WHAT ARE YOU TALKING ABOUT I DO IT ALL THE TIME ON MY CUSTOMER'S CARS NEVER HAD AN ISSUE"
Blah blah blah. I warn them that it's absolutely not a good idea despite how many times they may have gotten away with it. They don't believe me, think I'm making **** up and don't know anything about cars, challenge me to find any kind of expert that agrees with me.
So, I go to Kent's site at mercedessource.com and buy his $5 video on demand about how to properly wash a modern MB engine, and he uses an E430 to demonstrate. He twice says "DO NOT STICK A PRESSURE WASHER UNDER HERE" and it shuts them up.
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every wax on/wax off shop use high pressure washers to clean engines.
first they use solvent to losen up all crap then clean the engine with high pressure washers.
engine should be cold when doing this process.
then you can use high pressure air to blow of water in places like sparkplug area
first they use solvent to losen up all crap then clean the engine with high pressure washers.
engine should be cold when doing this process.
then you can use high pressure air to blow of water in places like sparkplug area
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From: A.D., U.A.E
2000 (W202 C200) & 2000 (W202 C55)
Also, not prefer to jet water directly to the Engine compartment, all harness plugs will affect, as well as coils/plugs/sensors/brake lines/fuse box,
"Bosch center" or "Würth" are good choices with warranty,,
or there are some good shops that provides steam Engine washes, it's more safe..
ZAYED,,
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From: America
1999 C43 AMG, 2005 E55 Wagon
misfire has been back twice lately, when the engine is cold. after it has warmed for 15 minutes, the misfire goes away
always cylinders 5 and 7. suspect some junk got in the coil connection or spark plug wires. will need to take them off and clean.
always cylinders 5 and 7. suspect some junk got in the coil connection or spark plug wires. will need to take them off and clean.
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From: America
1999 C43 AMG, 2005 E55 Wagon
I put a coil from my other car on cylinder 7 and I get no more misfires there. Now only codes for cylinder 5.
ordered a NEW coil for cylinder 5, now I get a misfire on cylinder 6!!
ordered a NEW coil for cylinder 5, now I get a misfire on cylinder 6!!
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From: City with Tall buildings!
C43/55,2k11 Volvo S60 T6AWD,2k Audi B5 S4,95 Eagle Talon Tsi AWD 500+awhp
Thread Starter
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From: America
1999 C43 AMG, 2005 E55 Wagon
guess it is about time for a plug/wire change anyway, though. I'm wondering if I got them dirty with the engine cleaning. meaning, I washed a bunch of gunk into them.
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From: City with Tall buildings!
C43/55,2k11 Volvo S60 T6AWD,2k Audi B5 S4,95 Eagle Talon Tsi AWD 500+awhp
Change the wires if no difference it's probably the coils if it is still misfiring. If the plugs were never changed it won't hurt to change them as well
