Northstar Engines and System Technical Discussion Discussion, DTCs from my flood car - help with diagnosis in Cadillac Engine Discussion; Hi all,
Using the great information I found here, I pulled the trouble codes from my flood-totaled DTS. As you ...
Using the great information I found here, I pulled the trouble codes from my flood-totaled DTS. As you would imagine, there are quite a few.....68 to be exact (yes, sixty-eight).
BUT....58 of them are historical and are from when I was powering up the car with random modules installed/not installed. There are only 10 current codes. They are as follows:
SDM: 3 of them, 2 because I don't have the RF side airbag installed yet. The third is because I haven't flashed the DIM with the serial number of the SDM. No big deal.
One is a theft deterrent module (transponder) failure. I don't care about that right now.
2 are stability system related, which is why my "Service Stability System" message is lit. One is the steering wheel position sensor, which is odd because it's sealed and has no moving parts. Second one is the yaw sensor which again is strange because it too is sealed. I have both those "spare" parts laying around. The column position sensor is going to be a b*tch to replace.
That makes 6 that are relatively minor.
Last 4 are powertrain. They are 300, 419, 440 and 1381. The 1381 is strange because it can only be current if a bunch of conditions are met, basically the car has to be moving. The car wasn't moving, so I may have jotted that one down wrong. In any event, it appears as if it's related to the misfire (300) anyway. The 419 is an air pump relay, I'll look into that later.
That leaves the 440 which is the EVAP vacuum failure. Basically the engine is trying to draw a vacuum on the fuel tank and can't. It's sending the "Check gas cap" message. Could the 440 and the misfire be related? I haven't replaced the gas cap, but the pressure sensor is new (came with the fuel pump assembly). What are common causes of the 440?
The misfire is still present after replacing the plugs and cleaning up the coil packs. The old plugs looked pretty bad - carbon fouled from way too much fuel. I haven't run the car enough to cause this - it must've been a condition before the flood. It has Denso plugs in it and it only has 46k miles on it so I think it's been fouling plugs. Fuel smells bad (water perhaps?) even though I put 5 gallons of fres stuff in it. All the plugs were wet. Only one looked halfway decent. I put a stethescope on the injectors and they all sound like they're firing. Doesn't smoke or make any bad noises, just misfires.
First of all I hope you pull out the PCM. If you didn't do it NOW. Open it and let it dry. Water will ruin electronics. After PCM gets dry check for any dirt inside. Clean it carefully. What about other modules, in a trunk? Turn on only if you're sure electronic moduls are dry. Change air filter (but I think you already changed that). It's possible that fuel pipes still have water in it. Don't crank starter a lot - you gonna ruin it too. If I was you I'll try disconnect all fuel pipes to get it dry also.
All the electronics are out of another DTS - all match and talk to each other fine. It's a little spooky actually because the car thinks I'm the pour soul who totaled that DTS. He likes his seat way back and the steering wheel low. Listens to rock stations too.
I just have a few of these minor issues.
Turns out one of the only modules I didn't replace - that yaw sensor - did indeed have water in it. It seemed like it was sealed, but it really wasn't. I have it drying out now.
Car runs fine, just has a miss to it. I've driven a little too, seems okay. I'm wondering if my misfire isn't just bad/old/water fuel. I got another 5 gals of fresh stuff to put in it.