ODB Help please.

[TRURX7]

95 Aurora
I got a code 25, 60, and P0117.
I need to find out if code 25 is my camshaft sensor or my air temperature sensor. If it is my cam sensor, where is it located? Also code P0117 indicated to me a QDSM sensor, does that translate to the coolant temp sensor? If so, where is it located?

Thanks in advance.

[thumpin455]

TRURX7,
I believe you are getting the Diagnostic Trouble Codes for the 1995 3800 Riviera mixed up with those of the 1995 4.0 Aurora. As you know the Riviera and Aurora share the same 2 book set of GM Factory Service Manuals. Book 2 of 2 "Driveability & Emissions" shows a listing of the Riviera DTC's in the front half of section 6E3. Apparently 1995 was a transitional year for the Riv and both OBD I and OBD II DTC's are shown. The 1995 Aurora was OBD I only and a summary of the codes are shown in the back half of section 6E3. The meaning of the former OBD I codes for the Riviera are different than the meaning of the OBD I codes for the Aurora even though the numerical value is the same.

On Aurora: DTC 15 = Engine Coolant Temperature (ECT) Sensor Circuit Open (Low Temperature Indicated); DTC 25 = No Spark Reference (24x) Crank Position Signal from IC Module (low voltage); DTC 60 = Park/Neutral Input with Cruise Control Engaged (trans not in Drive); DTC 117 = Shift "A" Solenoid/Shift "B" Solenoid Circuit Open or Shorted.

On Riviera: DTC P0117 (former DTC 15) = Engine Coolant Temperature Sensor - low temp indicated); DTC P0113 (former DTC 25) = Intake Air Temperature Sensor - high temp indicated.

You may want to get a service manual before throwing parts at it. Multiple codes will take some interpretation. Getting a code doesn't necessarily mean the sensor is bad. May just be the sensor doing it's job and indicating something is out of sequence or high/low value out of design parameters. Code 25 for instance may indicate a bad coil, ICM or even a faulty PCM. The FSM details troubleshooting for each DTC. By the way, is your engine running rough, shifting hard, or has it suddenly downshifted while cruising on the highway?? Let us know how it is running

[TRURX7]

Thanks Paul,

My car experiences the following:
- Transmission kicks when throttle is applied suddenly especially in slower speeds.
- Transmission does not downshift when gas pedal is applied fast and hard like in other automatics.
- RPMs fluctuate slightly in any speed.
- SES light comes on after about 5 minutes of driving.

Recently tuned up using Delco Platinums and Autolite Pro Wires.
Recently changed fuel pump, pressure regulator, and fuel filter.
Recently changed ignition module and all coils with AC Delco parts.

When I hooked up the ODB scanner to it it gave me the following information:
-Loss of 24X sensor signal
-QDSM sensor
-Cruise engaged when car is not in drive

I have a question with the first two.

[dsatt12]

For the downshifting part, I've always really had to romp on mine to get it to downshift. This is even after quite a lot of tranny work recently.

I think was Paul was getting at in part is that there are a couple of different sets of solenoids that are prone to failure in the tranny. One set won't let you shift up into third or fourth if they go in the same manner as mine did. The others are in the transmission itself (and I'm just going off their word that they fail a lot). Mine were good, but for another $70 in parts I had them replaced while everything was in pieces. I don't know about symptoms there.

That sucks that you replaced all that other stuff and still seem to have troubles.

[dsatt12]

One other thing that occurred to me... I had intermittent input speed sensor issues in my tranny for years that made for a veritable slamming into gear. It over time cracked all 3 of my transmission mounts. That's another $1000 on top of r&r of the tranny itself to get at them so they are still cracked (but holding together). If I get on my car while going slow or at a light it'll sort of kick or lurch some. In my case it's excess slop. If you get yours up on a lift the mounts are readily visible, and barring that a little work with a pry bar makes seemingly small cracks readily visible to the owner telling the mechanic that it looks fine to him

[TRURX7]

Where is this input speed sensor located? I have changed the solenoids on the valve body also and installed the small bracket they come with. Any idea what the QDSM sensor is?