99 E150 4.6 spark plug change
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99 E150 4.6 spark plug change
So my brother was driving our family conversion van that my parents bought new * important * and the CEL light came on. I scanned it when he came home and got a cyl 2 misfire code. I changed out the plugs and wires on cyl 1,2-5,6,7. And it got late so i started it up. It idled fine but as soon as I have some throttle it died or misfired. I may have crossed 2 coil plugs. But one thing I noticed were the plugs that came out were part number awsf32pg and the replacements I picked up were SP-432. The difference in the thread length is pretty decent but the plug is the same size. I need to finish replacing the remainder plugs today but any ideas on the difference in the plug thread size? It’s not the first time I’ve worked on ford engines (88 mustang owner) but I’m trying to figure out the easy startup issue and then cutting off once i give it gas. Even with mismatched plugs it should run.
Any ideas or input would be very helpful and appreciated.
John
Any ideas or input would be very helpful and appreciated.
John
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From: Fort Smith, Arkansas
The original spark plugs were short threaded because the head only had that many threads. The later heads got more threads so the spark plugs were changed accordingly.
No big deal.
Not sure why you wouldn't change all the spark plugs at the same time, especially the easiest ones to reach with the doghouse off. And you will probably want to get a new set of spark plug wires and be sure to plug them in correctly. You didn't say how many miles are on it, but since the plugs are original, the wires likely are too and at 20 years old they're done. Finish the job and double check the plug wire routing before you try troubleshooting around a mistake.
No big deal.
Not sure why you wouldn't change all the spark plugs at the same time, especially the easiest ones to reach with the doghouse off. And you will probably want to get a new set of spark plug wires and be sure to plug them in correctly. You didn't say how many miles are on it, but since the plugs are original, the wires likely are too and at 20 years old they're done. Finish the job and double check the plug wire routing before you try troubleshooting around a mistake.
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104k miles on it never had a plug change or wire change. Ironically it ended up being the new wires. Pep boys gave me the wrong ones. I’m figured it out by finishing changing the plugs nd installing the new wires. Same issue. Then I reinstalled the old wires. Runs mint. Seems like the new wires boot is a little longer and was not seating properly. I don't know but I took it for a drive and it ran smooth. The real test will be towing a trailer with band equipment (full gear and sound system set up) 30 miles for a wedding. But i figure since all we’ve been doing is hauling gear for the last 15 years and 90k it’s taken it’s toll on the engine.
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From: Fort Smith, Arkansas
The original Ford spark plug change interval is 100,000 miles for normal driving. Sounds like you were right on schedule for that. Many people, including myself, believe that is way too much time to leave a spark plug installed.
Glad to hear you got it figured out. I see a whole lot of people on here trying everything BUT an ignition tune up, and perpetually wondering why it misfires. "But the plugs are only __ (not very) old". Doesn't matter, if there is moisture in the hole, it's going to misfire. If the boot's not seated right, if the COP connector doesn't click, if you forgot to plug in an injector connector or COP connector, etc, ad nauseum.
I have found it is much easier to begin by troubleshooting the spark plugs rather than try to trouble shoot everything else first.
Glad to hear you got it figured out. I see a whole lot of people on here trying everything BUT an ignition tune up, and perpetually wondering why it misfires. "But the plugs are only __ (not very) old". Doesn't matter, if there is moisture in the hole, it's going to misfire. If the boot's not seated right, if the COP connector doesn't click, if you forgot to plug in an injector connector or COP connector, etc, ad nauseum.
I have found it is much easier to begin by troubleshooting the spark plugs rather than try to trouble shoot everything else first.
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2000Expy
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