Spark Plugs Fouled with carbon
02-23-2009, 08:37 PM
#1
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Spark Plugs Fouled with carbon
This is a 1986 300E, I have been using the Bosch Platinum quad plugs, but the car has been idling rough most of the time, but sometimes smooths out. I pulled the plugs and they are all badly fouled with carbon. Does not look like oil and they are not wet. They have been in for around 10,000 miles.
Looking for ideas that may be causing this problem. Maybe the plug fouling is not related and there are more than one thing going on. Wondered about the coil? ? ? ?
Any help would be appreciated.
Thanks.
Looking for ideas that may be causing this problem. Maybe the plug fouling is not related and there are more than one thing going on. Wondered about the coil? ? ? ?
Any help would be appreciated.
Thanks.
02-23-2009, 08:55 PM
#2
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lots of cars
You're running way to rich and you shouldn't be running bosch platinum spark plugs. You need Bosch Super H9DC or you can use the Champion equivalent but make sure it's the same heat range. You need to adjust your air mix on the air flow meter but it can be that your OVP relay is not working and not letting the EHA work properly. I would also replace the O2 Sensor with one from a 1990 mustang and just splice the harness in.
02-24-2009, 09:47 AM
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88-300CE TWIN TURBO, 99-C43, 05-G55K, 71-280SL, 94-E320 CAB, 08 CLK63 BLACK SERIES
You're running a plug that is not compatible with the W124 high tension circuit.
Use the specified non resistor plug or if you can find NGK BP5EFS which will work as good as the OEM Bosch.
Check your wires while your at it and if you replace them do so with an OEM spec set only !
Use the specified non resistor plug or if you can find NGK BP5EFS which will work as good as the OEM Bosch.
Check your wires while your at it and if you replace them do so with an OEM spec set only !
