Cross Post from Dodge Talk.
The hose did not fix the misfire in Reverse…
I now this sounds crazy, but my 2001 Dakota engine is running rough, but only in reverse.
In December, my son called to say the transmission temperature light came on while driving home. He was only a mile away, so I told him to drive on. He made it home without any problems. I got home a couple of hours later and checked the fluid. It did not smell burned. I took it for a drive. After 20 miles of so without incident, I figured it was some kind of fluke and started home. At about 27 miles the light came back on and it started shifting erratically (would not shift at the proper shift points) I was only a mile or so from home, so I drove it back. Long story short, a local repair shop replaced the Governor pressure solenoid and sensor and told me it was OK. It wasn't. After 50 miles or so, I was right back where I started.
Took it to a transmission shop. Complete overhaul. I got it back and it drove fine, shifted great and no transmission temperature light. But it felt like it was running rough in reverse. After about 75 miles, the check engine light came on.
I took it back to the transmission shop. They said yeah, we noticed it running rough. We think you need spark plugs and wires. My response "Why isn't it running rough in park or in Drive?" "And why was the check engine light not on when you got it, but now it is?" They insisted they had nothing to do with it… Pulled codes: P0301, P0303, P0305–misfiring on the left bank.
OK. I put plugs (Champion OEM), and plug wires on it. Same problem. I put a new distributor cap and rotor. Same problem. I ran a bottle of SeaFoam through it. I checked for vacuum leaks, I have gone over it and find no mechanical problems with the truck.
If you start the truck and idle in Park, it is smooth as butter. If you put in it Drive and sit still, it is smooth as butter. When driving down the road, it is smooth as butter. Stop, put it in reverse and it runs rough. It is not vibration, it is running rough, misfiring. Stand behind it when in reverse and you can hear the misfires in the exhaust.
I spent 12 years as a Ford master technician. I specialized in drivability from EEC III to OBD II. I have a good grasp on engine misfiring and this engine is misfiring. It seems to be lean at idle IN REVERSE ONLY.
Doe anyone know if the processor purges the canister in reverse? I have checked for vacuum leaks, but they SHOULD leak regardless of which gear the truck is in. The engine mounts are not bad and I see no real movement that would be causing something move around and cause a leak only in reverse.
The only thing I can come up with is this; there is a stud on the firewall that looks like something USED to be mounted on it, but nothing is there now. I can't say for sure something was there before the transmission work, but the threads look cleaner than the surrounding area. My hypothesis is that the transmission shop could have buggered something up while R&R'ing the transmission and just removed it… Dunno. A picture of the stud can be seen here:
Is something supposed to be mounted there?
Any other ideas?