: Check Engine Light Issues? Crankshaft Sensor? Please Help!

12-02-10, 09:42 PM
Hey guys, if you could help me out it would be greatly appreciated. I've been to two mechanics already and all I want is my Escalade back in top shape. Here is the full story.

3 weeks ago, my escalade suddenly started bucking and before I knew it I couldnt go over 25 mph. I shut it down and let it rest. I did this 3 times and I was able to make it to a mechanic in town. However the second time I did this, I had sparks shooting out of my tailpipe and my check engine light came on. That night they hooked it up to the computer and said it was a Crankshaft Censor? They replaced it, I drove it home seemed fine. Next morning I wake up and the check engine light comes back on. Send it back to the mechanic, he runs the computer on it, it shows several misfires I think it said cylinders 2,3,5,7 were misfiring. He tells me the car is running on less than 8 cylinders possibly but he clears the codes. Said it might be the fuel injectors but it most likely is just something pointless that that the check engine light is on. I decide to bring it to another mechanic.I bring it to another guy last tuesday.

New mechanic says the first mechanic put an aftermarket crank sensor in my Escalade and never calibrated and sync'd it properly. He puts in a GM crank sensor, re-calibrates it says im good to go. I drive it out, get it home. Go to fill it up for gas the next morning and the check engine light re-appears. What the hell is going on? I have no idea what to do at this point. It feels as if my Escalade simply doesn't have enough power, it seems rough and rumbly. Anyone have any idea what this might be? Im already up to 500 dollars in Crank Sensors. I just want this damn check engine light off. Anyone heard of something like this? Any help would be appreciated. Thanks guys!

12-02-10, 10:48 PM
I checked the FSM and was surprised to find there is a learn procedure for the crank sensor?!? Its quite detailed and through, the second mechanic u went to has a Tech2 scanner? Maybe the sensor wasn't the problem in the first place? In my experience those sensors either work or dont, causing the engine to run or not! Fuel pump ever replaced? TB ever cleaned? What codes are you getting now? If you plan on keeping your escalade for a bit a code scanner is a good tool to have. Keep us posted...

12-05-10, 03:35 PM
We replaced the ground wire located in the back of the motor. There was a tech tip we found from GM about the wire corroding. Now the scanner is saying its the CATS. My mechanic also said it could be oxygen sensors.

The car only has 64,000 miles on it, can it really be Cats? We never touched the fuel pump

12-07-10, 12:29 PM
Lmk what codes ur getting. I can post info from the FSM to diagnose the O2 sensors.