"Reduced Engine Power"

[O4L]

Thanks again to everyone for the help.

I remembered that after changing out the throttle body, both times, that it wouldn't go into the REP mode for several days. All that was done when changing it out was to disconnect the wires, and change out the throttle body, and reconnect the wiring.

So last night I unplugged the wiring harness from the throttle body for about an hour, then cleared the codes and reset the engine check light.

I am hoping it will act the same way again so that at least there will be some pattern to when it acts up. Right now it is very random.

 

[smcgee10]

I did not see the mileage on the 'burb. I ran into a problem once or twice that a coil going bad would create enough radio frequency interference that it would play hell with the PCM. Have you performed a tune up? Do the garages you take the vehicle to have an ignition scope and the personel trained to use it? That would be where I would start. Tune up, plugs, wires and scoping the coils to verify waveform.

 

[O4L]

This thing is still giving me fits! Resetting the PCM seems to help for a little while, but then the problem comes back.

Does anyone know if I can delete codes or make them a "non-error code" with a tuner?

 

[somebodyinok]

I had a similar experience with my car (2003 Jetta with drive by wire). It would randomly go into safe mode and barely run. I changed out TB's, changed out the pigtail that plugged into the TB, with the same random running conditions. What finally fixed my car was to bypass the factory harness wire with a complete layover to the PCM, viola, problem solved.

 

[NightShade]

I had a problem with a vehicle speed sensor in a neon that the wires had worked and one was broken. Rebuilt the plug and loosened the harness to relieve tension. Same thing happened with my dakota 4.7 the camshaft position sensor wires were tight so I actually extended them and rebuilt that connector and the evap system had a connector that was broken as well that I just spliced and removed from the circuit, that was code po 499.

As far as a tuner make codes irrelevant, theoretically that is possible but you would have to have someone specifically mod a tune to do that and by that time you probably spent as much as the cost to have that person fix it properly.

I run torque on my phone with an elm327 bluetooth obd2 adapter and was having a few issues at one point in my dakota on a long trip. I would use it to reset the codes, cycle the ignition and then keep going. The main problem with mine is that the cruise control would stop working when the light would come on and it causes pain if I have to hold the accelerator for 10 or 12 hours while driving on a long trip. Was going to phoenix from guthrie and it started acting up just the other side of amarillo. After a ways it would loose contact with the camshaft position sensor and I would reset it again. Got me through till I got back and fixed it properly.

 

[4play]

Seen a couple with broken wires at and near throttle body connector but sounds like you eliminated that. Check wiring around the throttle actuator control module, I had one that was rubbing body causing a short on the data circuit. The TACM is located on the LH/drivers side of engine compartment to the rear of the fuse box at the firewall. I hope those grounds I mentioned earlier were checked good because a couple I found had broken wires inside the insulation, a visual inspection wont catch that.

I have seen a couple electrical issues but not specific to the TAC being moisture getting into the PCM connectors. This is an easy step to check and eliminate, just unplug the connectors and look into the pins for moisture and corrosion.