Hi All, I have developed a intermitent engine miss on my beloved 1986 190e 2.3 8v The miss is most pronounced at idle in drive whether the engine is hot or cold at highway speeds it is either non-existent or hidden by the higher rpms. Last year I replaced the distributor cap and rotor and plugs. Any ideas ?
How can I test the plug wires I think one might be going bad and causing the problem ?
Would the miss cause my cruise control to cut out for a second when going over bridge expansion joints or is that a separate issue ?

By 'miss', do you mean an occasional misfire, or consistently not firing on one cylinder. If the latter, it is easy to check which cylinder is the problem, and then narrow down the cause. If the former, you still have to find out if the problem is on all cylinders or just one - inspecting the plugs for one with a difference is a good no-instrument technique.

Steve

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'91 MB 190E 2.3
'08 RAV4 Ltd 3.5
'83 Lazy Daze m'home 5.7

The intermittent engine miss was caused by one of my spark plug wires arching on the coolant housing. It was fixed by moving the wire to the side off the housing. Thats all that was wrong.

That should not be happening - time to get new leads.

I too agree it should not be happening - but it might not be the wires. Poor plug connection or a problem with that plug is more likely. Note it is vital when removing these connectors from the plugs to use an appropriate puller, else damage will eventually occur. I use a narrow-tip Visegrip to grip the crimp flange on the metal part of the connectors, which avoids any strain on the vulnerable parts. If you have been pulling on the non-metallic part, then best bet is to replace the wires or at least the ends.

Steve

__________________
'91 MB 190E 2.3
'08 RAV4 Ltd 3.5
'83 Lazy Daze m'home 5.7