I am trying to get my car back on the road to run powertour this June. I have a 1996 Avenger with the 4 cylinder and automatic. I have owned the car since 1997 and have 206,000 miles on it. The motor was refreshed at 160,000 miles with a stock style rebuild and ran fine after the rebuild. I used it as a daily driver until July 2013 and it has been parked since then with only a couple hundred miles put on it during that time. It was starting to act up and not running very well when parked.
In the last couple months I have been fixing problems and have gotten it much better but still have a nagging random stall that is keeping me from passing emissions tests. Based on research here I purchased the Torque android app and the bluetooth dongle to help in diagnostics and started working. I have replaced the following parts...
Crank position sensor - it was cracked and seeping oil.
Cam position sensor - it was leaking oil due to failed O ring.
Valve cover and spark plug well gaskets - one well gasket failed and filled spark plug well.
Plug wires - One wire boot sat in oil and was spongy
Spark plugs
Both O2 sensors - wasn't sure of age, probably original.
Vehicle side of upstream O2 sensor wire harness - 3 of 4 wires were damaged within 1.5 feet of plug.
Map sensor - wasn't sure of age, probably original.
IAT - wasn't sure of age, probably original.
I pulled the battery and air intake tube to inspect the wiring harness that runs along the driver side of the motor just above the EGR. I removed all loom and tape and was unable to find any burns or damage to any wires. I put it all back together ensuring it was tied up away from the EGR tube.
I inspected the wiring harness coming around the passenger side of the engine that includes the two coolant temp senders, PS, AC and upstream O2 sensor. The only problem I found in any of those wires was damage to 3 of the 4 wires going to the upstream O2 on the vehicle side of the harness within approximately 1.5 feet of the plug. I purchased a replacement pigtail and spliced it in. Everything was rewrapped, loomed and hooked back up.
The car started on first crank and idled normally for a few seconds. After a few seconds it wanted to stall, I was able to keep it running by giving it a small amount of gas. It idled for another second or two then tried to stall again. At that point it idled fine and needed no interaction from me to keep it running. I watched the torque app and the car entered closed loop and all other readings looked reasonable. I then started driving and again all readings looked reasonable. The coolant temp stayed between 160 and 170, intake air temp was around 100 and I stayed in closed loop the whole time. I drove in the city for approximately 15 minutes between 20 and 40 mph. The first monitor to go to a complete state was the EGR system and then catalyst. I stopped and idled for a couple minutes then turned the car off for 10 minutes. When I started the car I still had EGR and catalyst showing complete. Very shortly after starting the car and driving again I had the stall and all monitors went to incomplete including misfire, fuel system and components. I was moving when it stalled this time, it was very short and did not need to stop or restart the car. It was just a momentary loss of power like a hiccup. I then drove for another 20 minutes in the city without any further stalls. During that time the EGR system went back to a complete status.
I have a feeling it is a damaged wire somewhere but would appreciate some guidance. Does the heater in the upstream O2 run constantly or only at start/long idle? At this point my gut says it is somewhere in the ASD relay to the power side of the upstream O2 heater.
My apologies for being so long but I wanted to be thorough. Thank you
