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Q: engine runs rough(miss fires) at 2900RMP on 1998 Volkswagen Jetta

I've changed the MAF sensor, Cap and Rotor, plugs/wires and even added fuelline antifreeze and it did not improve, any ideas of any thing else i could check
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I had the same problem with my 98 jetta and went through wires and cables and all the such. I purchased a new ingnition coil and it ran fine. make sure the coil is audi\vw because one that I purchased as a replacement wouldnt run the car properly and it was a canadian tire part.
If the misfire is ignition related you may have a crack or electrical fault in the ignition coil.
With the engine running spray the ignition coil and cables with a mist of salty water. This will "stress" these areas of the ignition system.
Any electrical leakage will become evident as an immediate misfire or visible electrical arcing.
If you have access to an appropriate scan tool you can confirm fuel mixture , if it is random multiple misfire fault or a specific cylinder misfiring.
The direction you take in repair starts with that information.
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