Hello. I've been slowly trying to do research on a surging issue if that's the way to describe it. I've read multiple causes and saw that it could be a MAF or a MAP Sensor issue. So, that leads me to a question. Our 2008 HHR currently has almost 238k miles on it and to best of my knowledge the MAF and MAP Sensors have never been replaced and have the original sensors. The MAF the last I looked at about 2-3 months ago appear to look fine. So far, I've got no codes or CEL on the dash at this point. I have thought about just leaving them alone but, wondering if the replacement would be worth it at all considering these sensors are now 17 years old? Thank you in advance.

 

No cel lights? Leave the sensors alone! However you could clean the MAF sensor. Use sensor safe MAF cleaner.

 

Have you cleaned the throttle body?

 

Use throttle body cleaner to do that , and do not manually move the butterfly plate, you might strip the plastic gears and that will be the end of your throttle body! New ones aren’t cheap!

 

I second cleaning the MAF sensor. The slightest bit of almost invisible fluff, too little to trigger a code, will interfere with its optimal function. I've lost count of the number of times that this has helped a slightly annoying stumble or miss.

 

Hello, sorry for the late reply. I looked at the MAF Sensor when I changed the air filter a while and I couldn't see anything alarming but, I could be wrong? As for the throttle, I did try to carefully clean just a little bit but, generally left it alone for the most part at this point.

 

Remove the throttle body bolts and gently lift it up, do not move the throttle plate or disconnect the wire harness, squirt the throttle body cleaner in both sides the reinstall in to the intake manifold.
Give the MAF sensor a squirt of MAF sensor safe spray , let dry and reinstall it.