Bad plug?

olefafl · #1 04-05-2003, 10:24 PM

Just got back from CO, and pulled a 6X12 U-Haul trailer back to IN.

Total mileage on the truck 107,984.8
The trip was 2,266.5

Going out, got 13.5 - 14 mpg.
Coming back sucked - trailer, no overdrive.

Stayed the night in Kansas City. When I started it in the morning, it was very rough. Thought I had bad gas. Two different trucks (a year apart, one gas, one diesel) don't like Colorado gas. Filled up several more times once out of Colorado. Didn't feel like it was running bad at high speeds. No check engine light. Stopped to eat, and when we got out, foul-smelling brown eruption oozing from radiator overflow. Engine never got hot, and gauge read normal about the "O". After half an hour, fluid level normal. Brown probably due to Bar's Stop Leak over winter.

Still running bad, have not checked anything but a very quick look under hood, looked OK.

The truck is a 95 F150 ext-cab, 5.0L, AT 4R70W, 2wd, short bed

Miles · #2 04-06-2003, 05:11 AM

Pull your plug wires one at a time and see if there is a change in the engine while running. If you pull one and there is no change thats the missing cylinder. Use gloves and insulated pliers though or you'll get zapped.

olefafl · #3 04-06-2003, 11:11 PM

Replaced the plugs today, didn't help. They all loked good.

Then replaced the cap and rotor, helped some. It looked like crap inside.

At work on Monday I will replace the wires, and hope thats it.

I will be replacing the Accel parts that were installed about a year ago.

When I was testing today, I pulled 2 different wires at the cap and it didn't change how it was running.

ccnseven · #4 04-07-2003, 09:49 AM

Man Accel stuff usually last more than a year. Sometimes on a v8 hearing a miss at idle when you pull a wire off can be difficult. How does it run when driving at highway speed?

olefafl · #5 04-07-2003, 07:52 PM

Replaced the wires after work, may have helped a little.

Will replace the coil next.

Has a little miss a speed, hard to tell.

When I pulled the wires at the cap to check the plugs, on 6 of them you could tell it was different.

Pics of the cap, rotor, and plugs will be posted soon.

olefafl · #6 04-07-2003, 09:13 PM

Here are the pics.

More here. http://www.f150online.com/galleries/...w.cfm?num=1043

Miles · #7 04-07-2003, 10:43 PM

Whoa, man! That cap and rotor are fried! The plugs are not in the greatest of shape but with a careful cleaning and gapping they'd do a little more.
I had an unexplainable miss for about 6 months and I finally broke down and changed wires and cap. It turned out the wires were cross firing. They were only a year old with little mileage and I couldn't believe it. It turned out the guy that put them on had them twisted under the intake where they weren't easy to see.
I put on Excel Superstock wires and cap and cleaned and gapped a virtually unused looking set of plugs and viola no miss!
Be sure to use the wire looms that are on your engine and if they come in your new wires use'em. Its a real good idea to keep your wires from touching anywhere to prevent crossfiring.

ccnseven · #8 04-08-2003, 03:40 PM

Man, that rotor is toasted, replacing that sure outta help you're gas mileage and power

olefafl · #9 04-08-2003, 06:58 PM

Replaced coil today, may have helped a little.

I will see the Mac man on Wed, and get a fuel press. tester.

What should the press be on a 5.0L?

I also ran 2 tanks of inj. cleaner, on the way to CO. Could I have a plugged inj? Can I replace them with higher flow without any problems?

I have a K&N, and a Edelbrock cat back, thats it.

dave186 · #10 04-08-2003, 11:37 PM

your plugs arent all the same color, they should all be a nice white-tan. could be some sort of fuel problem maybe. or they might not have all been firing all the time with that cap and rotor.

olefafl · #11 04-09-2003, 11:27 PM

I replaced the TPS today and it runs a hole lot better now, still may be a little miss, will be able to tell more on Thur.

The Mac man wanted $300.00 for the fuel press. tester. I can put a guage in my truck for under $50.00.

He will have an inj. tester for me next week.

I may put the Accel coil back and see how it does.

olefafl · #12 04-10-2003, 06:57 PM

When I replaced the TPS I had the battery unhooked and when I started it back up it ran fine on the trip home.

Today its back to running like crap. I will get to put a scan tool on it Friday, but it never put the "Check engin" light on so I don't know about any codes.

olefafl · #13 04-11-2003, 10:09 PM

No codes, but the o2 is not showing any volts. It should show 0.35-0.55 volts new one will go in, hope that takes care of it.