QuestionI have a long history with my truck trying to track down an electrical gremlin. It's an 87 Eddie Bauer edition with a rebuilt 86 Mustang 302. Only reason I know its an 86 Mustang is because that's the only year spark plug that will fit it. Same with the oil sending unit. Here's what happens. Driving down the road, 55 MPH, everything's fine, running good and all of a sudden I lose my gas pedal. Truck continues to run as I have power steering and power brakes, and the RPM's and speedometer start to go down real slow like I would have just let off the accelerator. After this, two outcomes can happen:
1. Truck continues to slow down until it gets to about 10 MPH and then finally turns off. Check Engine light comes on and I lose all power. Always starts right back up though.
2. Truck regains power to the accelerator and I continue down the road. Could be 5, 10, 15 seconds of no power, then all of a sudden it kicks back in.
I have tried everything, replaced most of my sensors. I pulled codes and I got the following.
KOEO 31 81 CM 51 87 31
KOER 21 44 31 77 52
I do not have my EGR valve hooked up and pretty much all of my smog related devices are non existent from whoever rebuilt the motor. I direct wire the fuel pump relay to the dash board to make sure I could control the fuel pump. The issue I described above happens when the truck is sitting still or moving very slowly and at that point just dies.
PLEASE, anything you can point me to would be huge. I'm just about out of patience, and vacation time at work :)
Thanks Todd. Let me know if you need any additional information.
AnswerI am assuming that this is a full size bronco and you have used the mustang computor.
as for codes
31= Evap emissions- ignore
81= AIR management- ignore
51= Coolant temp sensor- repair this
87= never heard of this= please confirm
31= Evap emissions- ignore
21= Coolant temp sensor- repair this
44= AIR management- ignore
31= Air charge temp- fix this
77= never heard of this= please confirm
52= never heard of this= please confirm
Common power loss failures like this are the Ignition module on the distributor. It usually fails at specific temperatures and causes loss of spark. If you let it cool or open the hood ,it may fire back up. I always carry a spare if in the bush or on a trip.
Secondly is the Cat or exhaust may be plugged causing a restriction. Engine will often run but relly lacks power until the blockage falls away and exhust clears.
To check this you would need to measure exhaust backpressure as the problem occurs
