HELP, RUFF IDLE .. ONLY SOMETIMES
 

HELP.. 94 C280 125k on it...
Runs like a top till you slow down then it is ruff as all get out.. punch it and it acts as if it is running on 1 cylinder...

shut off the car and start it right back up.. Perfect... runs like a top...
only happens after about 50 miles... then all the time, but works fine as long as I re-start it...


ANY IDEA'S???

Had to be electrical to me, but what?????

RE: HELP, RUFF IDLE .. ONLY SOMETIMES
 

the fuel injectors affected are being shut down because of knocking or values which are out of tolerance.

read for fault codes.

when did it first happen? after refilling fuel? bad fuel can cause this.

RE: HELP, RUFF IDLE .. ONLY SOMETIMES
 

Engine light never comes one.. it just shakes like crazy wiht NO power...
Happens at any point... Full tank empty, hot day cold day.. no rime or reason to it...

If I punch it it will go , just splitting and sputtering like crazy....

I did run some top quality fuel cleaner thru the system and changed the fuel filter..

RE: HELP, RUFF IDLE .. ONLY SOMETIMES
 

okay dude, have ur spark plugs checked. weak sparks can cause rough idle and severe power loss. also, see if you can have your engine foam cleaned. They spray an anti-carbon foam into your engine that breaks down all of the carbon inside the engine in your cylinders. if you do this after you get the other problem fixed it will run like new...only better b/c its broken in. it's worth the money if you have it done professionally b/c it will restore all of your response and power plus the engine will run smoother. Also, check for any kind of fluxuation in oil pressure or engine temperature as these could be signs of further problems. good luck, PM me when you find out what the problem was, i would like to know.

RE: HELP, RUFF IDLE .. ONLY SOMETIMES
 

MAS, o2 Sensors, WIRE HARNESS!

RE: HELP, RUFF IDLE .. ONLY SOMETIMES
 

Try checking the knock sensors. Make sure they are tight on the block under the inlet mainfold. Also check your spark plugs for tracking marks down the insulators. These marks look like someone has drawn a pencil line down your spark plugs porcelin, and if this is the case, you also need to replace the connector on the offending spark plug/s

RE: HELP, RUFF IDLE .. ONLY SOMETIMES
 

i say engine wiring harness, or maby air map sensor
and at a guess your car may not even have a check engine light?

RE: HELP, RUFF IDLE .. ONLY SOMETIMES
 

I have the exact same problem with my 05 c230. It is in the shop right now with a #2 cylinder leak and #3 exhuast leak. I will let you know what the shop says is the problem.

RE: HELP, RUFF IDLE .. ONLY SOMETIMES
 

sound like you may have alot of problems especially with 125 million miles on it you need to have the codes read with a hht of aftermarket equivlent. plugs coil harness all are possible problems

RE: HELP, RUFF IDLE .. ONLY SOMETIMES
 

HELLO!!
Just fixed the same problem on my 94 c280 with 100k on it bad coils and plug wires. However be expected to replace the engine harness shortly, ( i am in the process of trying to keep my $ from my local dealer for parts).
thanks,steve.