I have a 1997 F150 with the 4.6L. It is a 4x4 extended cab with 198,000 miles on it. The engine has developed a really bad miss. I changed the plugs about 10,000 miles ago. What are some of the things I should take a look at?

This truck also has a terrible squeaking noise in the left front suspension. Could this be the lower a-arm bushing? What can I do to make the noise go away other than replacement?

 

Loose plug, poorly-seated fuel injector, bad COP, etc. You should have a Check Engine Light, right? Can you have it scanned and post the code?

 

I had it scanned at Autozone when I had the check engine light flashing. It said I had a lean mis-fire on the #2 cylinder. I found that the injector had come unplugged at the time. I plugged it back in and it ran fine until recently. The clip on this injector does not seem to hold tight. Every time I check it though it appears that the injector is plugged in so that lead me to believe I have a different problem.

Any thoughts on the squeak??? Thanks!

 

How long ago was that scan? I would have it scanned again if you don't think it's the same problem.
Trying to take a shot in the dark on a miss like that isn't going to be very fruitful. If you at least knew which cylinder it is, we could start with a diagnosis. For example, if you knew for a fact it was the #2 again, I first clean the connection for the injector and secure it to the injector. Then test it. If it still misfired, I would replace that spark plug and test. If it still misfired, I would swap a COP with another cylinder and test. Misses on the same cylinder? You're back to square one and maybe you've got a bad injector or a bad connection to the injector. Know what I mean? It's just hard to tell without knowing which cylinder.

I would fix it asap so you don't mess up your catalytic converter(s). If you had a flashing check engine light, your cats may have already taken some damage.

Sorry, I'm pretty inexperienced with front-end stuff so I've got nothin' on the squeaking.

 

Its a 97 model 4.6 so it doesn't have coil on plug ignition. It has 2 coils & plug wires. I'd change the wires & plugs & see if that helps

 

I think I will take it in and have a complete tune up done. When I changed the plugs the one on the rear passenger side was nearly impossible to get to with the tools I have.

I think the Cat. converter has went bad, too. Maybe time for the exhaust my son keeps after me about getting!

Question: what is a COP? I have never heard that term.

Thanks, guys!

 

A COP is a Coil-On-Plug system. Instead of plug wires, I have individual coils that sit right over each spark plug. But like Lariat97 pointed out, the 97's didn't have them. My mistake.

You can test the Cat with a vacuum test, but if after you get a tune-up you're having problems getting higher RPM's, it's a safe bet that your cat is clogged. Most likely cause in this case would be unburned fuel leaking into exhaust system and combusting there.

 

Thanks for the info on COP. I had never heard of that. I think a good tune up is in order for my truck.

One more question unrelated, my son's 1987 f150 4x4 has a noise in the left front hub area when he turns. It is a "clanking" noise. I have checked the wheel bearings and they are very good. I can move the drive axle with my hand when I have the hub off. Not rotate but move it up and down a little. If anyone has any thoughts on this I would appreciate hearing them!

Thanks!

 

If you do decide to beef up your ignition system, please take a look at our F-150 Firepower Ignition System at:

http://www.performancedistributors.c...50ignition.htm