A442F Transmission Issue UPDATE: Seems like a motor issue instead. (1 Viewer)

[Red Merle]

Checked all of the grounds I might have bumped. No change.

 

[Red Merle]

You say it sat for six weeks. Is there a possibility that a rodent is involved here somehow?

I checked the air filter. That looks fine. Is there something else I could check? I don't see any signs of mice nor any gnawed wires.

 

[ZackR]

So it surges like that with the throttle steady in one position? Will it rev up any higher or is that as far as it will go?

 

[Red Merle]

So it surges like that with the throttle steady in one position? Will it rev up any higher or is that as far as it will go?

Yep. That is all it will do. When I first plugged the ECU back together, I was able to get it to rev up more like normal but when I tried to drive it, it went right back to this. I am holding the throttle steady in the video and I can't get the RPMs up beyond that. It's almost like a limp mode or something.

I am hesitant to try the new ECU if there is something surging and frying the old one.

Would disconnecting the battery and trying to reset the ECU make sense?

 

[LINUS]

^^^Couldn’t hurt trying to reset the ECU.

Plus gives you a reason to bump the terminals again - another thing I notic is you had the whole relay box folded towards the motor.
As hot as that EFI relay runs, I would pop the cover & give your relay a little jiggle & see if the wires to the relay board are old & tired. If you keep a spare relay & your cover isn’t sealing perfectly, maybe some schumutz or corrosion got in there.

 

[Red Merle]

^^^Couldn’t hurt trying to reset the ECU.

Plus gives you a reason to bump the terminals again - another thing I notic is you had the whole relay box folded towards the motor.
As hot as that EFI relay runs, I would pop the cover & give your relay a little jiggle & see if the wires to the relay board are old & tired. If you keep a spare relay & your cover isn’t sealing perfectly, maybe some schumutz or corrosion got in there.

I tried disconnecting the battery. No change. I will look at the relay box. That was moved around a bit during the project.

 

[BILT4ME]

Unfortunately, I cannot view YouTube videos at work.

How about the VAF (MAF/AFM...) is it functional? If you unplug that harness does it NOT start? Does it die? Is the VAF operational?

(Just remember...DON'T undo the screws and yank on the harness.......)

Do you have your oil fill cap on and tight? PCV? Throttle Body vent hose?

 

[gearinstalls.com]

Clogged exhaust? Maybe something in the Cat is going on?

 

[gearinstalls.com]

....and how about the possibility of a clogged fuel filter.....or if your fuel pump is in the gastank with a strainer then maybe the strainer is gummed up.

 

[Red Merle]

I think the AFM, or MAF or whatever it's called on the '94 is functional. I didn't mess with it during this, but I have never touched the screws as I know the issues that causes.

Fuel filter has less than 10K miles on it and I just replaced the tank and fuel pump with working used ones, although it could be the pump, I guess.

Exhaust is also entirely new in the last 10K miles.

For this project, I replaced all of the AC components, the main crank seal, the oil pump seal, the new inner and outer fender on the driver's side and replaced the hose from the power steering reservoir down to the pump. Before that, I have rebuilt the entire top end of the motor and everything ran perfectly for two years prior to this.

Caps and hoses seem fine.

 

[ZackR]

Based on how thoroughly everything has been dialed in up to this point I'd focus on the electrical, grounding, ECU direction...

 

[Red Merle]

I took the battery out and checked the EFI relay box and that all looked fine. I did find this mystery plug that comes out of the same wire bundle as the ABS wires but also the wires that run into the relay/fuse box. It doesn't appear to fit on the ABS pump that I removed, but I can't see what else it would mate with and I think I would have labeled it if I unplugged it for this project, but I might have missed it.

 

[george_tlc]

I'd check grounds again, the igniter gets its ground only through its body. Worth verifying that the thinner ground cable from the negative battery post is securely bolted to the fender and that the igniter bracket is securely bolted to the bracket/fender etc.

Just one more thing to tick off your checklist.

cheers,
george.

 

[ZackR]

The 4 conductor plug you have unplugged looks like it goes to the brake fluid level sensor. Small red arrow on mine.

 

[Red Merle]

The 4 conductor plug you have unplugged looks like it goes to the brake fluid level sensor. Small red arrow on mine.

View attachment 1798702

Mine is hooked up to the brake fluid reservoir. This is for something else I think.

I checked all the grounds again before I put the battery back in and I am still having the issue.

Would there be a reason to NOT try the new ECU?

 

[Red Merle]

I'd check grounds again, the igniter gets its ground only through its body. Worth verifying that the thinner ground cable from the negative battery post is securely bolted to the fender and that the igniter bracket is securely bolted to the bracket/fender etc.

Just one more thing to tick off your checklist.

cheers,
george.

What is the igniter?

The grounds look fine.

 

[ZackR]

Igniter is I2:

 

[george_tlc]

The igniter is what drives the primary side of the coil. Poor ground connection would make for erratic coil/spark.

Modern vehicles have way too many sensors/connectors/wires/doodads for our own good...

cheers,
george.

 

[Red Merle]

I tried shooting some dialectric grease in the igniter fitting and I removed and cleaned the grounds from the wire that goes from the center of the distributor to the black box mounted to the fender. No change.

 

[Red Merle]

One last thing I could mention. I did get the motor wet three days ago when I cleaned the hood insulator pad. I checked under the distributor cap and it looks dry, but water could have gotten into something, just not sure what else to check at this point other than trying the new ECU.

It's also running really rich. I can smell unburned fuel in the exhaust.