1993 ford explorer bogging down, transmission noise?

[FredDoug]

I’m here looking at it right now and I checked the plug wires again and they all look good. The shaking has slowed down and it seems to be running much better than last week. I took it on a test drive but didn’t make it far when I started to get a popping sound in the front (right?) of the vehicle when accelerating. It made me think it was misfiring. Couldn’t repeat it by just pulling on the throttle with the hood open though. I checked the codes and got 157 again and 543 which is new. The 543 code I found says “fuel pump monitor circuit shows no power”. Thoughts?

I have cracked open the pcm and from what I’ve seen online it goes bad when those capacitors puke out the bottom usually right? If so then it doesn’t have that problem

 

[FredDoug]

After some looking around I wonder if 543 is stored from when I unplugged the fuel pump relay to take a look at it when someone suggested it could be the problem.

 

[FredDoug]

I forgot to post this but I ended up pulling out all the spark plugs again and making sure they were all torqued down to spec and in right after someone suggested that I couldn’t put them in too far or cross threaded them. I noticed this time that all the spark plugs in the driver side of the engine were much dirtier than those on the passenger side. Could this maybe point to something? The valves perhaps?

 

[ChildIdenticant]

The valves perhaps?

Performing a leakdown test will help assess this. Tester kits are inexpensive, might be able to borrow from an auto parts store. Can also make one from parts at lowes/home depot etc.

 

[FredDoug]

Alright so I ended up ordering an iac and tps from rock auto. I also got a leak down tester but haven't used it yet.

After installing the iac and tps there were some changes. The explorer didn't want to cough out and die nearly as bad as it did before, which was kind of a symptom that appeared with the misfires. It still has an inconsistent misfire when you initially try to accelerate when cold. Makes me think it's a partially plugged fuel injector. Once it warmed up though it no longer seemed to have a misfire. Which makes me think leaking cylinder.

On my drive around the block though it had a jerky motion in second and third gear. It would lurch like it was trying to accelerate and then feel kind of like it was braking. Then repeat that over and over. It makes me think slipping clutch. Or it could be related to the misfire.

I also reset the codes and so far don't have any new ones. Just lots of 1's flashing. Any ideas other than the leak down tester which hopefully I'll get to soon?

 

[Bboy]

Update on this car. I'm the brother who was originally helping on this. I swapped out the computer with one that my buddy got at a junkyard for one of his projects. The explorer now has it's power back, revs and accelerates well. It does seem to be running rich, and pops/back fires often from the passenger side (I believe my brother mentioned this happening before as well) it seems to be running rich, when. I first started it it was idling at 2k rpms and once it warmed up a little went to 1500 rpms but that's still pretty high. Like I said it also backfires from the passenger side so I think it's that bank running rich (it feels like it's running on all cylinders though). It also jults or bounces when you accelerate hard. I'm going to put pictures of the to computers, I'm wondering if it's the wrong computer or not but the computer was definitely the problem. The silver is the old one and the black is the new one. Any input would be helpful.

 

[Bboy]

Opened up the old PCM today and did find a slight leak in one of the capacitors.

 

[Turdle]

I'd try replacing all the can caps on old ecm.

 

[ChildIdenticant]

That can be enough to give bad days. Remove the conformal coat around the caps. Desolder the caps (note orientation, they are polar). Clean those areas. Look for and repair damaged trace. Verify continuity through vias. replace with new caps. Verify continuity again. tada.
inexpensive 30w iron is sufficient for the solder on these boards.

 

[donalds]

You're lucky you caught it before it damaged your board