How in the world????

[Curious Hound]

Ok. So I have a misfire in cylinder #4. It's a 97 F150, RWD, 4.6l. 122,800 miles

I thought I would pull the plug and look at it. Well, #4 is in a tough place and that's a severe understatement. I haven't even got the wire disconnected yet. So I tackled #1 to see what I'm up against. With pliers, I got the mile-long boot off the plug and got the plug out. It's ugly and burned open to 0.09" gap. #2 is the same. They should be 0.052-0.056". So I think maybe #4 is probably worse. Hopefully, new plugs will fix this.

What is the trick to getting these wires disconnected? I can barely get my hand back in there. Come on, Ford techs. Hand over your secret. It's hot out here and I need to be moving my crap out if the ex-wifes house. Not fighting spark plugs.

 

[Dirtman]

Get a boot puller. There's a bunch of different kinds but I found these work the best for getting really hard to get at wires.

 

[Curious Hound]

Get a boot puller. There's a bunch of different kinds but I found these work the best for getting really hard to get at wires.

View attachment 30434

Wow. Never saw one like that. I have the old style plug wire pliers. But they won't work on these. Not enough room to get them in there and they don't really open up wide enough. These boots are really shaped weird. I'll take a picture of one.

I just got the passenger side plugs finished. I had to dismount the huge "mega fuse/ distribution block thingy and tie it out if the way. That helped a little bit. So far on the driver side, I have removed a steering pump reservoir bracket, some kind of vacuum actuator and a bunch of vacuum lines and cables. I can actually see all the plug wires. It would be nice to get the fpr and fuel rail out of the way. But I don't want to mess with that if I don't have to.

 

[Curious Hound]

Here is what these boots look like. The plugs are way down in a deep mine shaft into the motor somewhere. Can't even see them.

 

[Dirtman]

I never messed with a 3.0, I thought the wires on my 2.3 were bad! The boot puller was my only idea lol. Hopefully someone who's worked on the 3.0 will chime in with better advice.

 

[Curious Hound]

I never messed with a 3.0, I thought the wires on my 2.3 were bad! The boot puller was my only idea lol. Hopefully someone who's worked on the 3.0 will chime in with better advice.

This is the 4.6 in my F150. Posted in the full-size trucks area. Just have one more to do. #8 is gonna be as bad as or worse than #4. Fuel rails, fpr and egr hard piping in the way.

 

[Dirtman]

Duh... im an idiot lol.

 

[Curious Hound]

Duh... im an idiot lol.

Not sure about that. I'm the one who just spent 3 hours changing 8 spark plugs. That time does include the trip to O'Reilly and Advance and a few short breaks to cool off and post here.

 

[adsm08]

On the 97-03 body style with the 2V engines there is no good way to get at #4 and #7.

#4 is even worse on an Expedition with rear air, one of the AC line Ts to the rear is right on top of it.

 

[Dirtman]

At least it's not a Triton 3 valve. Easier to just buy a new truck than replace plugs on those.

 

[Curious Hound]

Just test drove with the new plugs. Same problem. Running really rough and no power. Has not set a code or CEL yet. Seemed good when I first started it. But when warmed up, it went bad. That makes me think the coil packs are ok and something else is wrong. I'm going to go to the junk yard and see what I can find. ECT, MAF, coil packs, egr parts.

 

[Dirtman]

ECT would be my first guess if it runs fine until warm.

 

[Curious Hound]

This morning it was bad at first cold start. So I guess the temperature thing doesn't matter. I replaced the ECT anyway. I'm hearing a ticking noise, mostly on the passenger side. Sounds like a sewing machine. injector noise? Also have replaced both coil packs with junk yard units. They seemed to be aftermarket units since they didn't have the Ford label with part number and wire connection numbers. Anyway, no change. I cleaned the MAF with official MAF cleaner. Also replaced the dpfe sensor with a junk yard unit and the vacuum servo that controls the egr. No change. No codes have been set yet. So the ECU isn't helping me out very much. I'm about to go to Advance for a set of plug wires and harbor freight for a fuel pressure gauge set. O2 sensor voltages displayed by my obd2 reader and Torque Pro app seem to be all over the place. When I get back and the exhaust is cooled down, I'll try to verify that the O2 sensors are connected alright.

If I don't get this today, I'll take it to a dealer tomorrow. But I don't want to have to do that. NB besides, it's a bear to drive right now.

 

[Curious Hound]

Fuel pressure seems to be ok. It maintains 32psi while running even if I apply throttle a good bit. Goes up to 39psi if I remove the vacuum line from the regulator. I'm watching to see how long it maintains after shutting down the engine.

 

[Curious Hound]

I think I fixed it. The spark plugs may have been my only problem in the beginning. It appears that I didn't get all the wires properly seated. Found 3 that were off. Drove it a bit and problem came back. Found another one creeping back out. I think they're alive NB and once they tasted freedom, they don't want VB to NB stay down in those holes. I bought new plug wires today. But they will have to wait for a cooler day.

Just proves that I'm the dummy today.