P0303 and P0758

I know what both of these codes are (Cylinder 3 misfire and Shift Solenoid 'B' Electrical)

The strange thing about this is that the car will misfire, but if I pull over and clear the code the misfire goes away temporarily. Same with the 758 code.. If I pull over and clear the code, it'll shift fine until the code comes back. Other than this the car is great, no more white smoke and coolant in the oil.

Anyone ever heard of this?

Btw, it's a 2001 SS

 

Now I have another code showing up (P1860) which is a transmission code, P0758 hasn't came back. I was driving with the scanner plugged in and the p1860 came up which apparently makes the car not want to move. While driving, I cleared the code and the car began to run fine again. Could it be a loose connection to the PCM? I had it out..

 

Those codes are for internal transmission solenoids. They are probably going bad. Check the wiring harness where it goes into the transmission (right below your intake arm/throttle body). Unplug and plug it back in while the car is off. If the codes come back, you will need to replace those failing solenoids.

Your P303 needs to be addressed. Check the spark plugs and wires. I have had a P300 that was random, and the engine ran fine. Yours is specifying one cylinder. Best of luck.

 

Thanks for the reply!

Well I did a compression test and cylinders 1 and 5 had 150psi, and #3 had 110. I did a leak down test and confirmed that it's losing compression through the intake valve. I'm not worried about that, I can take the head back off and repair it. I just don't understand how I'm getting several transmission codes, that when I'm driving and clear them, it shifts fine? Just now I drove to the gas station with the scanner plugged in. It stopped shifting, had codes for shift solenoid A & B. The second I cleared the codes, it shifted fine. Doesn't that seem strange?? Plus I'm suddenly getting evap codes. Can this be a bad ground wire somewhere? I don't like removing transmissions on W body's and will avoid it at all costs haha.

 

Or how about this... While I was tightening the exhaust pipe to the front manifold, I ended up cracking it somehow and the engine compartment is extremely hot. The leak is right above the trans, could it be getting too hot? I'm actually about to go get a pipe from the junkyard.

 

You could check the ground wire under the ICM bracket... But those solenoids fail in tricky ways.

 

Hmm, that actually broke when I took the ICM off the head. I wasn't real proud of the way I had it put back on. I just checked it and it was loose enough to move very easily. That can cause transmission codes? Today is the last day I can work on it until next weekend, so I'll go cut one off at the junkyard and put it on the right way.

Oh, by the way, I stopped getting the P0303... It changed to P0304 then P0300 for multiple misfires. I might have fouled out the plugs with some really heavy valve cleaner that I put in straight through the main vacuum on the back that connects to the booster.


Thanks again for the reply!

 

Shouldn't cause transmission codes, but could very well cause misfiring. No problem, glad to help.

If you're talking about seafoam, it shouldn't have fouled the plugs like that.

 

I just brought it to a transmission shop and the guy confirmed that there was no power to the harness that plugs into the trans. He told me to try splicing a wire from the pink/power wire to the trans fuse. I did that and it works. I drove it for about 45 min with no trans codes. Obviously I don't want to leave it like that... Any idea where to start looking for a bad connection with that pink wire?

 

All you can do is trace the pink wire back to its root... You could check the PCM connector, but you probably have a short somewhere in that wire.