Loss of power
 

My wife called me at work and said she bearly made it home the 95 C220 suddenly idled rough and had no power (well know this 4 cyl eng is guttless) but this is alarming. I hooked up the scanner and it gave me a code P0304 cylinder 4 misfire. Any ideas? Thanks in advance.

98 ML320
97 C230
95 C220
95 318ti

Start by checking ignition components - Plugs, wires, cap and rotor (if that car has a cap and rotor)

Inspect all your plugs. If the one in cylinder 4 is dramatically different from the others, there may be something going on in that cylinder that is fouling the plug.

If there is no obvious cause in your ignition system, then I'd check the cyl 4 injector.

Loss of Power
 

Well I swapped parts to see any improvements so far no luck. R & R sparkplugs, sparkplug wires, OVP,fuel pump relay, fuel filter, cam position sensor. Still the same hesitation (misfire) next will be the fuel pump & the ignition coils. Yes I threw parts on it but most of these parts I already have with me.
No check engine light, no codes stored.This thing is kicking my a*s :eek:

98 ML320
97 C230
95 C220
95 318ti

Maybe exhaust blockage....one bad cyclinder while certainly noticeable, should not affect power to where your wife barely made it home...Can happen dramatically if something breaks loose in the exhaust train.

Bad ignition coil
 

With the engine on idle I pulled each spark plug wire one by one when I got to the number 4 wire there was no difference when the sparkplug wire was pulled off. Now the fun part of replacing this coil which is mounted under the intake manifold.

98 ML320
97 C230
95 C220
95 318ti

Car update
 

C 220 running fine after replacing both ignition coils, found out the wire harness ($$$!) is not that healthy and would need attention in the future.

98 ML 320
97 C 230
95 C220
95 318ti

i just did one of these and had to replace that wiring harness as well.