Canadian Hummer Club Forums

My 2005 H2 has been running weird for about a week, at 60 kph if you let off the gas, slow down a bit and then back on slowly it wibrates and shakes, same thing around 80 and again at 100 kph. Mechanic says mass air flow sensor is bad, he cleaned it and this solved the problem for a day or so but now it's coming back again.



First question, is this the real problem, and how do I replace it.



Any help, thoughts or suggestions would be appreciated.



Thanks,

Jony 5

Do you have access to a code reader? Even if the check engine light isn't on the computer can still hold codes to help you know what is going on... You can usually pull multiple codes depending on the nature of the problem, so it wouldn't be uncommon to see 4 or 5 codes or more from the scanner.



The basic code readers will just pull the error code, then the owner would probably just Google the code to find the meaning. Many of them are universal among a family of vehicles so many GM trucks share many of the same error codes (long story short, Google will easily find the meaning to the error codes).



That'd at least give you some indication as to what the problem is, sometimes interpretation of the codes is best left to a professional as to the root cause, but I say give'r!



I don't know if you have a tuner or other device to read the codes? There's lots of devices that will pull codes, so not just the expensive professional grade devices. My Hypertech tuner will pull codes, and the ScanGauge I have will also pull codes. Hypertech is just shy of $400 and the ScanGauge retails for about $160! Considering the cost of shop time something like a ScanGauge is not a half bad idea, since that's like 1.5 hours in most shops and even less in many dealerships! Pays for itself pretty quick... As for the cause of the problem I'm not really qualified to speculate, but the mechanics diagnosis is definitely believable and personally would be the first thing I'd look at replacing.



Good luck! Let me know how it goes!