I feel as if I have stepped into a giant black hole

The other day my 98 started misfiring and today I decided I was going to do the plugs and wires. I thought that maybe I could have just had a loose plug wire so I pulled them all, inspected them, and then reinstalled them. I started my vette and it fired up real nice. I decided to take it around town for a quick cruise and to get gas. As I pulled out of my driveway I heard what sounded almost like my brakes were grinding (the noise your brakes make after a car sits in the rain and gets some rust on their rotors) My Vette is always garaged tho so I know the rotors were clean. Anyway, I drove until the next driveway and pulled in to turn around and go home to inspect the car, but after I backed out and got going straight again the noise was gone?

After that I decided since the noise was gone I'd still go and get gas. On my way to the gas station I noticed I didn't have power steering anymore I filled up my tank anyway and wanted to cruise around a bit longer to see if I'd start misfiring again. After about 30 seconds of driving at the bottom of my gauge cluster it started flashing "traction system enabled" and I'd feel myself being forced to slow down. Seeing that I was only going 30(ish) and applying little pressure to the gas pedal with no bumps or wet pavement, there is no way there was a traction issue. It kept flashing the same "traction system enabled" readout over and over so I turned traction control off and slowly went home. With traction control off is stopped flashing "traction system enabled" (obviously)

Long story short, I do not know why my car misfired or if it is still misfiring. I do not know what the temporary noise was as I was pulling away from my house. I do not know why I don't have power steering anymore. I do not know why my car flashed "traction system enabled" when there is no traction issue.

Can anyone help me diagnose any of my problems without taking it to a shop right away?

 

Wow, all hell broke loose on the Vette. I'd first check to see if one of your pulleys gave up the ghost and killed the belt. That would be the grinding as the pulley bearing locked up, and the loss of power steering as the belt came off. The misfire is still a mystery though, could be lots of things. But first get the hood open and have a look around.

 

Then pull the codes.

http://www.stengel.net/diccodes.htm

Post back which codes you have.

 

I checked the pulleys and belts and everything is intact.


I have the following codes:

10-PCM:
P0171 C (Fuel Trim System Lean Bank 1) - I am assuming this is because I got 243 heads, a cam, BBK intake mani +TB, headers + exhaust, and a CAI without a tune right?

40-BCM:
B0432 H,C (Rear Defogger Relay Circuit) - The wire attached to the back glass is broke
B0502 H (RH DRL Relay Circuit)
B0507 H (LH DRL Relay Circuit)
B2482 H (Backup Lamp Relay Circuit)
B2597 H (Traction Control System Switch Circuit)
U1016 H (Loss of Communications with PCM)
U1096 H (Loss of Communications with IPC)

A0-LDCM:
U1064 H (Loss of Communications with BCM)

A1-RDCM:
U1064 H (Loss of Communications with BCM)



Should I maybe drive around some more and see if I can't get a "28-TCS" code to come up? I pulled the codes yesterday and if I am not mistaken there were 3 "28-TCS" codes with "H" next to them. I guess maybe I hit reset instead of option tho because now it says there aren't any codes for that section. Could clearing old codes in the "28-TCS" section cause my traction control system to start acting funny? I mean, my Vette never had a TCS problem until after I accidentally cleared the codes.

Could driving it around with traction control on and malfunctioning hurt the car at all? I mean, I've gotta drive it in order to get it to throw a TCS code right? I've heard horror stories of people's brakes locking up and it costing lots of money to fix....That won't happen to me right!?!?

 

Anyone have an Idea?

 

Erasing codes will not affect anything. All you are doing is erasing information stored in the module's memory. TCS codes will always have history after them if the engine is off. The TCS system resets every time the engine is turned off. If you want to see current codes wait until you get a Service message on the DIC and pull over to the side of the road and run the diagnostics without turning off the engine.

If you are getting the DIC Message that Traction is Active there may not be any codes because that is the message that shows up when the system is working correctly. Have you changed tires recently? What you were getting sounds like a traction activation due to the rear tire being a smaller diameter than the front tire. I am talking tire diameter not wheel diameter.

I take it you car doesn't have Active Handling.

You will not hurt the car if TC is activating incorrectly just push the console button to turn it off. TC is a feature of the ABS system and it isn't a necessary for proper functioning of the car. It is no more harmful than having a radio that is acting up.

Bill

 

You need Bill Curlee for this one. Maybe PM him to get him involved. Maybe a ground problem or battery leakage on the PCM wiring? I'm surprised it still runs, mine won't start let alone run if I even think of the letters BCM.

 

With all the LOSS OF COMMS codes,,,something is effecting the serial data buss. The most common thing that causes that is the door module wiring harnesses. That would be the first place that I would look. Pop out BOTH door accordion tubes and fish out the TWO door wiring harness connectors for each door. Disconnect all the connector and clean the connectors, inspect the connectors and isolate any bare wires with liquid electrical tape. Then reassemble the connectors and see if that resolves your issue. Make sure that you clear ALL the DTCs after repairing the door wiring harnesses to see if there are any more issues.

Another common area where the serial buss can become compromised is the drivers seat plug. That plug sees a lot of abuse and can become damaged and short out the serial data buss. You have to get rid of ALL of the loss of comms issues before you try to resolve anything else.

BC

 

I cleaned the door harnesses and the one under my seat was in good shape. I drove around for a while and did NOT throw any new "loss of comms" codes.


I still do not have power steering though, and my traction control is still engaging when there is no tire slip. I found I am fine through first gear (even if I mash the gas pedal) but as soon as I shift to any gear and give it more than 1/10 throttle traction control engages and slows me down. I originally thought that maybe one of my brakes in the rear was sticking and the uneven resistance might be causing the car to think that there was tire slip but upon pulling into my garage when I would push the clutch I would roll backwards with ease (my garage isn't very slanted at all so I really can't see how I'd roll if I had sticky brakes)


Any ideas?

 

All the sensors that tell the EBTCM what the car is doing and what you want the car to do, all have to work in a Calibrated Orchestra. There are acceleration sensors and Yaw (Left - Right) position sensors, brake pressure sensors, Steering wheel position sensor, Wheel Speed Sensors etc.. They all work together and their output tells the EBTCM where you want to go and which way the car is going.

If you have the steering wheel in the 000 (straight ahead position) and jab the accelerator and the rear end KICKS OUT to the Left, the EBTCM will apply braking specific wheels to straighten the car out. If you JAB the accelerator and roast the tires, the EBTCM will use the Wheel Speed Sensors (WSS) to compare the speed of each wheel and apply brakes and pull timing and close the throttle to reduce wheel spin,
If the WSS or some other sensor is giving false signals, the EBTCM or the EBTCM is malfunctioning it will apply braking to the rear wheels.

You should see the point now. If you can find someone who has a GM Tech II,, it can pin point the issue quickly. Other wise, your going to real familiar with schematics and DC Volt meters.


If one of those sensors is giving false signals, what your experiencing will happen. One of the highest failure rate sensors is the Steering Wheel Position Sensor (SWPS)

BC