slight miss from idle to 2500

[NDSHO]

Need some help. I am new to the SHO world. Just fell in love with this car that I bought for $600. When I got it, it had a miss from idle to ~ 2500. I changed the plugs and wires first thing and that fixed it... for about 50 miles five or take. Now it's back again. Also, she runs just above the cool mark. Is it possible that the engine is reading cool and fouling out the plugs? Please help. Going crazy here. And by the way, I think this sight will teach me a lot about my new Ford/Yamaha. Thanks to all who contribute.

 

[NotSoSlowSHO]

Welcome to the forum!

What kind of plugs and wires did you install?

SHO is VERY picky about plugs.

 

[NDSHO]

Bosch Platnium2 and Autolite Wires.

 

[NotSoSlowSHO]

First thing I would do is install the proper Motorcraft plugs.

The wires should be fine, although I doubt they seal against the valave covers properly.

Also, have you checked for oil in the plug wells?

 

[NDSHO]

That was the first thing I noticed when I got the car. There was a small amount of oil in the front three wells. I sucked as much of it out as I could before removing the original plugs. I compared the original wires with the new set, and the length of the boots were the same. Why is she so picky about Motorcraft plugs?

 

[NotSoSlowSHO]

I dont know... but the Yamahammer sure is picky about plugs

Have you checked the REAR plug wells for oil?

Running with oil in the plug wells will damage plugs and wires.
The only way to fix it right, is to replace the plug well seals along with plugs and wires at the same time

 

[NDSHO]

Yep, I did check the back three and there wasn't anything. Judging from the spill marks, it looks like some ******* spilled oil while filling at one time or another. I do understand the effect oil has on plugs and wires, but what I don't get is why after replacing them, it seems that they may have fouled out again. Could it be that it's not fouled plugs, but instead be a plugged fuel filter, or bad TPS? I've been skimming some of the other posts but no answers at the end. Only suggestions. All I do know is that when it wasn't missing for that 50 miles, that car was damn fast for being all stock. I can't wait to get it running to it's full potential.

 

[Dr. Tweak]

The oil in the well is caused by aged plug well seals, and they need to be replaced.

http://www.shophoenixproject.com/upper60k/upper60k.htm

And by searching the forum:

Missing caused by fluid in plug wells and other problems:
http://www.shoforum.com/showthread.php?t=27904
http://www.shoforum.com/showthread.php?t=7480
http://www.shoforum.com/showthread.php?t=9411