Thanks to all for looking. I have an issue with our 1998 5.0 explorer. Last evening my wife was driving home. Vehicle was running fine, transmission was shifting as it should. Then all of the sudden it just lost power, but remained running. She was able to limp home in it. This am I went out to look into it.

Start the engine...sounds fine. Put it in gear and it starts to stumble. My initial reaction was that one of the ignition coils had gone bad. So I uplugged one and started the engine, then the other. With either coil unplugged it ran far worse so I am assuming (maybe incorrectly) that the coils are functioning properly.

Last year I replaced the plugs and wires with bosch products.

So I decided to take it for a ride and see whatever else I could figure out. From a start, it bogs real bad and sounds like it's only running on a few cylinders. Once the car is rolling 30 mph or so if you barely touch the gas, the engine sounds better and is more reponsive. However, the engine still misses pretty badly. It feels like it wants to go, but then hesitates and then feels like it wants to go again but the same thing happens. All this seems like an ignition problem to me.

However, I was able to get it to about 55 mph. At higher rpms the engine is a bit more responsive if I am very light on the throttle. But the transmission is not shifting out of 1st gear.

So I am confused. It seems unlikely that both the engine and transmission would start having problems at the same exact time. Any ideas are appreciated.

Thanks,
Paul Ruffo

 

Try cleaning the mass air flow sensor.. if debris gets stuck up on the elements it can cause all kind of driveability problems.

If that doesn't fix it try scanning for codes...

Other things you'll need to check for - proper fuel pressure, restricted converter(s), plugs/wires/coils (your coil test isn't exactly valid), cam/crank sensors.. the list goes on and on...

Let us know if the MAF cleaning doesn't fix it, and what, if any codes you find.

Good luck

 

Pulled the codes...looks like I should blow it up!!

P1747
P0750 - shift solenoid A Circuit Malfunction
P0755 - shift solenoid B Circuit Malfunction
P0743 - Torque Converter Circuit Electrical

Any input would be appreciated.

Thanks,
Paul

 

check for low Battery voltage, alternator output, both will trigger these symptoms

 

Checked voltage...at battery 12.6. With engine running...14.4

Was researching on alldata...it says that code P1747 - Electronic Pressure Control Circuit - indicates that the EPC is not getting a voltage reading or the reading is low. As a result, it lowers tranny line pressure and limits engine torque output.

Alldata says step 1 is to check the EPC plug. It is located just above the right rear corner of the tranny pan. Problem is all the exhaust is routed throught that area and it is nearly impossible to get to the plug in order to check it.

Anyone have any tips on getting to this plug?

Thanks,
Paul

 

Fixed...bad EPC plug.

thanks guys,

Paul