GMC Tire Pressure Monitor Light On

Question:
I have a 2010 GMC Terrain & I have purchased new wheels and tires for the winter season and wondering about the RPM (tire pressure monitoring sensors) . Do I need to rematch them or can I run through the winter without rematching them? Is there a warranty issue here? The reason I switched wheels is that my Terrain came with chrome wheels and I don't want the salt here to pit them.

The new wheels are powder paint coated. The new wheels have the sensors already installed. Will the vehicle DIC system operate properly without rematching? I can live without the tire pressure monitor as it is not accurate anyhow.

Answer:
Your vehicle will not automatically match with the new sensors in the new wheels/tires. There would have to be a relearn procedure done to accomplish that. This procedure does not have to be done if you can live without it. You will, however, have a 'Service Tire Monitor' message on the DIC and the light on the dash of the little tire with an exclamation point will be on continuously. Neither of those will hamper driving or any other functions of the DIC or vehicle itself. It would just be dealing with the message and light on all the time, so if that doesn't bother you, you don't have to get the new sensors relearned to your vehicle.

If you do want to get that done, it would need to be done with a tire sensor learning tool. Many shops now have this tool, it is quite expensive, but to be safe that it is compatible with such a new model, i would suggest the dealer. Expect to pay approx. 1/2 hour labor for that.

On a side note, if you do decide to get the sensors in your winter wheels/tires learned to the vehicle, you will have to do the procedure again in the summer when you switch back to your original wheels/tires. The vehicle will not recognize them once other sensors have been learned.

Question:
2007 GMC Acadia shakes, shudders, and has a hard time accelerating when starting from stop or slowing down and then speeding up again. When first initially give it gas until the RPMs climb to above 2K then runs ok.

Answer:
You could have a misfire caused by a spark plug or ignition coil. Or you have a timing issue. You need to get the computer scanned for trouble codes. There are many problems in your style vehicle that relate to cam timing, timing chains stretching, cam actuators/phasers and even fuel injectors.

From what you describe, you are likely a victim of one or more of those issues. You would need to take it to a dealer where they can hook up a scanner and see exactly what is going on and where the problem is. If your vehicle has less than 100,000 miles, it may very well still be under GM's powertrain warranty and wouldn't cost you anything to fix. If it is out of warranty, it is definitely going to be an expensive repair, and usually the engine has to be removed from the vehicle to complete repairs.

Question:
2008 GMC Acadia where is the rear ac unit located? Have a new motor i need to put on but cant find the housing unit.

Answer:
The rear heating and air conditioning unit is located inside the right rear quarter panel trim in the back of the vehicle. You will need to remove this panel, which has many clips and screws to gain access. Once removed, you can access the entire rear unit and repair or replace what ever is needed.