When It Rains Bad, My Car Runs Terrible, Mind Of Its Own

5point0stang88

Active Member
Sep 9, 2011
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Why could it be that when it rains bad, my idle hangs at 2k of it'll either erratically and stall. Also driving it jerks, and rides rough. Only thing I can come up with, is the connection plug is getting wet for the o2 sensors? I have long tube headers so I have extensions and they do hang lower than the car at the moment.

Mind you, dry weather and light rain car runs completely fine. Only when raining bad to where water builds up on the road.
 
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The only factor is water so it's the obvious culprit. The only question is which item is it effecting. I'd start with the MAF first then work back. If the fan controller is wet, is the filter?
Has to be, both suggestions are the same. Wire element getting wet, I'll have to devise a shield of some sort over the filter
 
Ignition misfires maybe. High spark plug resistance. Any moisture can let ignition charges short to the block or to an adjacent ign wire. Also check the dist cap for cracks and carbon tracing. When is the last time you replaces the plugs and what kind are in there?
 
Ignition misfires maybe. High spark plug resistance. Any moisture can let ignition charges short to the block or to an adjacent ign wire. Also check the dist cap for cracks and carbon tracing. When is the last time you replaces the plugs and what kind are in there?
There other thread mention same thing again, I do have wire that has broken boot due to touching header, I've checked, it arch's when close to header
 
I've had to shove little pieces of ceramic tile between plug boots and header pipes to solve arching. Crude but effective.

But again, if the spark plugs have high resistance, the charge will find an easier path to ground. The result is misfire. Then your O2 reads rich and can start to make other things get out of wack.
 
Granted it's not raining today. But I wrapped the burned through portion of spark plug wire with electrical tape, and resecured the connection on the act sensor in my intake tubing. As a quick fix to help I hoped.
Idled at a perfect RPM, smooth throttle response as well as felt more torque the entire drive to work. Better than normal on dry days. I think I'm on the right track.
 
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There are high temp fabric boots that you should slip over the affected spot on a new wire. Advance Auto or any real speed shop should have them.

Dielectric grease on the contacts of the cleaned and resecured connection should help water resistance.
 
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