Mid range/ under load misfire.

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Dec 23, 2019 | 09:07 AM

SamT

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Mid range/ under load misfire.

Some of you are probably familiar with my truck.
92 f350 5.8 5spd 4.10
low miles, 63k, but it sat for 3 years and has most likely been used intermittently for 10 or so year.

i have been through a host of problems. i thought I had the truck running good, but it was just a dog on power until I put some new exhaust on yesterday. (True dual Glasspacks, too dang loud. ) Now I hear a pretty serious miss under a load. I’m confident it’s in the ignition.

im going to town today and will buy cap, rotor, wires and plugs. I peeked in the cap and it looks like hell inside. So I think I’m on the right track.
all looks to be original. Wires look great.

so far I’ve done. TPS, iac, O2 sensor, fuel filter, air filter, oil change, alternaternator. Anything besides the ignition tune up parts that I should round up while In town?

Dec 23, 2019 | 12:28 PM

sandymane

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From: Houston/Sugar Land

You might want to rent or buy a timing light if you don't have one. Get Motorcraft parts for the other parts on your list if you can. To many iffy parts out there to waste time and money on. Sandy

Dec 23, 2019 | 12:31 PM

SamT

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Quote:

Originally Posted by sandymane

You might want to rent or buy a timing light if you don't have one. Get Motorcraft parts for the other parts on your list if you can. To many iffy parts out there to waste time and money on. Sandy

i have a good light, I’ve been too lazy to read whatever the timing process is. I guess I put the new parts on and do it.

Dec 23, 2019 | 12:34 PM

sandymane

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The miss under load would certainly be suspect for timing at least being checked.

Dec 23, 2019 | 02:11 PM

torq'ta 5 8

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wires look good could potentially be 10 years old, I'd get new ones you already there, and the regular autolite copper plugs

Dec 23, 2019 | 02:47 PM

sandymane

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Quote:

Originally Posted by torq'ta 5 8

wires look good could potentially be 10 years old, I'd get new ones you already there, and the regular autolite copper plugs

I think he is talking about the wires in the distributor looking good. He is getting new plug wires. Sandy

Dec 23, 2019 | 04:22 PM

SamT

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Quote:

Originally Posted by sandymane

I think he is talking about the wires in the distributor looking good. He is getting new plug wires. Sandy

so cap and rotor looked like hell, plug wires looked great but I bought new ones. Plugs looked good besides #8 I don’t believe was firing. The coil to cap wire had major corrosion on the coil when I pulled it.

runs good and sounds good now. No intermittent check engine light either now.