Pity7700

Don't post much here but I'm in need of some info.

Just added a 96 short bed regular cab 5.0 to my garage.

I'm getting a P0385 (crank sensor) and codes for O2 heater circuit on each O2 sensor.


Anyone have a similar issue? Crank sensor is new, checked timing, insured all connections made.

I've read that these codes both could be caused by a faulty PCM.

The previous owner of he truck did some crappy work on it, wrong injectors, gapped plugs all wrong, hoses not hooked up properly, worn out parts, said he replaced a bunch of stuff but definitely did not.

The truck runs 10000xs better now after I fixed plugs, injectors, wires, distributor cap and rotor, vac lines, new gaskets and a bunch of other stuff. Trying to tackle this final issue.

Chris_1

iTrader: (1)

Might want to clear the codes and see what comes back.

Pity7700

I've done that at least 20 times by now trying to fix the issue along with others. Keeps popping up.

sdmartin65

Does the balancer for sure have the tone ring?
With a light on it does timing move when running?

Pity7700

The ring is on the balancer. I can check in the morning when I get up if the timing moves while its running, I didnt notice it move at all when I checked yesterday but I'll check again.

Pity7700

Checked timing again today, let the truck warm up for about 30 minutes. No change in timing.

I am getting an RPM reading on my scanner while the truck is running.

sdmartin65

On obd2 you always repair codes in order they appear, so I'm assuming the po385 is the first code. I would remove the new sensor take it to the parts store tell them it's bad and exchange for another. Start running some basic continuity tests on the wiring. Use contact cleaner and go at the connector. Use dielectric grease when re connecting. It very common on all types of automotive connectors for the rubber water protecting boot that goes inside the connectors to be missing. Falls out when pulling connectors apart. The connection then is prone to corrosion.

Pity7700

Rechecked connection at sensor, cleaned it and made sure it was secure. Ran the truck without the sensor plugged in, ran the same as it did with it plugged in, same code. I will run and get another sensor tomorrow.

I did check the resistance of the sensor but I can't find what my reading should be i got s resistance reading of 3xx ohms. Trying to find a range for the sensor.

The first code that pops up is for the o2 Hester circuit. Bank 2 sensor 1 which is brand new. The truck has a hollowed out cat that the previous owner did. It's possible thats where the code is coming from. After driving for a few, all 3 o2 sensors throw the ssme code.

Crownman

If the cat is hollowed out and there's no MIL eliminator on the rear sensor you'll get a code and a CEL. However, the rear sensor doesn't affect the way the engine runs so it won't cause any problems. The 2 front sensors are what the ECU reads to adjust the parameters while running.

Have you replaced the upstream O2 sensors? If you have are you 100%sure they're the correct ones? It seems very odd that they each throw the same code at the same time.

Pity7700

Right, I was wondering why all 3 were popping up, that's why I suspected the PCM being bad since the O2 heater circuit codes and the crank code can be due to a failed PCM.

Bank 2 sensor 1has been replaced with a universal sensor by the PO.

I'm chasing the wires back to the PCM for the crank, everything seems to be intact. Gotta run a couple more tests on the crank sensor to determine what's going on. Found someone with a similar problem on the same year truck and motor.