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Electrical Miss/surge

  • Thread starter Thread starter 87_LX_5.0
  • Start date Start date Aug 19, 2014

87_LX_5.0

Active Member
Aug 24, 2010
142
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29
Uniontown, PA
Aug 19, 2014
#1
  • Aug 19, 2014
  • #1
Here's a little history of my car. It's a 1987 coupe that was originally a 4cyl. It was converted to 5.0 by an unknown owner an unknown time ago. I purchased the car from my wife's uncle in August 2010 and have driven the car religiously over the last 4 years without any major issues. The car and engine is relatively stock with the exception of all the emissions equipment which was to my knowledge never installed during the conversion. Again, I've never had any drivability issues with this car until recently.

Earlier this spring the stock 75a alternator crapped out so I replaced it with the 5.0 Resto 3g kit. Also installed this year was latemodel's CAI. My car is still speed density. About 2 summers ago I did a full tune up which included new Ford/Motorcraft plugs, wires, cap, and rotor. The plugs, wires, and cap that were removed idn't seem to be in too bad of condition with the exception of appearing old. There were no signs of damage or abnormal wear.

Last month I began having an infrequent slight miss. Thinking it was possibly a tank of bad gas I ran a bottle of additive through with a fresh tank of 93 octane. Over the next couple weeks miss became progressively worse and more frequent. Also, about 2 weeks ago I started to develop a surging idle. This also became progressively worse since. I started with the Surging Idle Checklist and quickly eliminated the IAC or Map as the culprit. Suspecting a faulty TPS since the idle would surge from approximately 800 to 1600rpms+ and stay there I tested the voltage and found it was set at .80v. I did adjust the TPS to .91 but I do not think this is the issue since it is not radically out of whack and within the .6v-1.0v range. I have not dumped codes as I except numerous codes related to the nonexistent emissions on my car. Again, no drivability issues in the 4 years I have owned it.

So today I pulled the cap and discovered what appears to be oil (?) in the bottom of the distributor. Now I'm no master mechanic but I don't ever recall seeing oil down there. Also, all of the contact points on the bottom of the cap and the rotor contact area were covered with a white chalky substance. This car has always had the smell of running a bit rich but I figured if it wasn't broken I wasn't going to mess with it. My main concerns are the apparent oil and white on rotor and cap. I'm assuming the iginition system is getting hot and causing the build up? I've attached few pics. Let me know what you guys think. I'm figuring this is the source of my issues but what is causing it.
 

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stykthyn

I want to measure mine. It doesn't look that tall.
15 Year Member
Jul 6, 2006
5,232
2,652
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gainesville
Aug 19, 2014
#2
  • Aug 19, 2014
  • #2
The build up is normal. Clean with scotch brite or if you haven't done sui in a while replace the cap and rotor. As for the oil, is it on the outside? If it's on the inside well I've just plain never seen that happen.
 
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