markes12344

Hi all here is a quick spec.

NEW:
302 HO
Ignition coil
Wires
Spark Plugs
NAPA Idle air control Valve, Throttle Position Sensor
Venom Injectors

PROBLEM:
I have a irregular exhaust sound. the engines near smooth but when ever the sound changes there's a slight shake. every time the exhaust changes sound for anywhere from one to three cylinders i get more exhaust out my tale pipe as it pushes on my hand harder.

The irregularity in the exhaust cancels out the thought of it being a spark plug or wire. as it tends to be a different cylinder when ever it wants to.
I'm leaning towards Ignition coil or capacitor near it. or the EGR valve.

Also no Codes are present.

markes12344

Just took it to a mechanics for a quick listen and ideas to this problem. he thought a possible misfire. I replaced the distributor cap and finger. made sure the wires were ran to the plugs the best i could get them so they were not cross firing.

Still have this problem where its like every so often a cylinder/cylinders misfire, yet more of a over fire as more exhaust is being pushed out when the sound changes.

Forge-World-FORD

Have you checked your timing? If not, don't forget to take the spout plug out when you do.

jgrove998

I've always heard to stick with Motorcraft IAC's; at least that's what is recommended for my Merkur. I had a unknown IAC on my truck and pulled a Motorcraft one from the junk yard...cleaned it and installed; idle is much smoother.

markes12344

Timing is at degrees with spout removed.

This is the only thing i will have to yet do. As the IAC i installed is a Napa brand. Anyone ever hear if the TPS needs to be Motorcraft too?

Forge-World-FORD

At what degrees?

markes12344

sorry 10 degrees. not sure how i missed that

Forge-World-FORD

That's normal. Is there any problem with your IAC or is it just a non MC part? Try seafoaming? Is it worse under load or does it stay the same whether the truck is moving or not?

markes12344

haven't sea foamed the truck as the engine rebuild only just made a year in july.
IAC appears to be working but i would almost wonder if it is not slightly adjusting constantly at idle, that is why i get this flutter. as for driving down the road it seems fine, smooth, at a stop i can feel a bit of a shake. If i have the hood up and apply throttle to a constant rpm, the engine does get t fainter flutter than what it does at idle. i guess the only part that i can see replacing could help is the IAC vavle to a MC part instead of Napa's. that is unless the MAF sensor can be the culprit, but i don't think so.