2007 Chevy Equinox Engine Sputter

I did exactly this (actually replaced all spark plugs to be safe), and also inspected and cleaned the MAF sensor, but the sputter still persists. Any other suggestions? Because this is happening during the shift on acceleration to highway speed, is there any chance this could be a transmission issue?

Well I broke down and took the car to the dealer. It turns out that the tech there used to work on Saturns and recognized the problem as a "sticky" valve that has apparently been a problem in the Saturn Vue among others. It will probably take the rest of the week to get the right parts in and ensure that the problem is fixed for good, but the great news is that it's all covered under the powertrain warranty.

Thanks for your help!

Hello.

My Father has recently had this exact same problem with his 2007 Equinox. He bought it new, it now has 90,000 km (55,924 miles), and it also jerks/sputters/stutters when accelerating past 80km/h or 50mph. He has already gone to the dealer and their diagnosis was, like yourself, that a couple of cylinders were misfiring (which seems to be a common problem around the internet for these vehicles). The diagnosis alone cost about $100-150 and they wanted $850 (CAD) for replacement of the spark plugs, ignition wires, and cleaning of the fuel injector (ridiculous).

Naturally, he decided not to take the dealer's asking price for repair and took his car to the garage he frequents and got the spark plugs replaced. The day after, the same problem surfaced again.

After further research on the internet, it seems like the likely cause is the ignition wires and arcing that can occur between spark plugs. Who knows really. That being said, he has decided to return to the garage tomorrow and get the ignition wires replaced.

Regardless, it seems like you went through the same process and 'band aid' fix and it still had problems a couple of months later which is a little disconcerting. If you would be so kind, could you perhaps tell us if the 'sticky' valve solution truly fixes the problem later in the week? My Father would appreciate it greatly and in retrospect, myself as well, as our family will be taking our annual 1500km road trip to east coast for fishing and this would really be a hamper to our vacation. Not to mention if a car problem were to happen this year, it would be a second time in as little as three years that the family car broke down while driving to our fishing spot (this time, it would our new car as the previous car's transmission died completely and we had to purchase the Equinox out of desperation. Crazy story really).

$850. Sad.

Yes, I will be happy to do so. It has been 4 days so I will probably speak to the service department again today.

Just an update, the dealer is in the process of replacing the valve and 2 cylinder heads, and I should have the car back at the end of the week. We shall see whether this fixes the problem for good.

Thank you for the update.

My Father's car is working perfectly after replacement of the spark plugs and ignition wires for the past few days so far. Hopefully, it won't crap out.

Thanks again.

Well, the good news is that the technician at the dealer was able to identify the sticky exhaust valve, replace it and the related cylinder heads, and over $3000 of repairs were covered under the powertrain warranty. The tech told me that they needed to perform a running compression test, which was new to him, and in this way they identified the cylinder / valve where the compression was well below normal operating range.

The bad news is that my wife called me to report that on her way up to highway speed this morning, there was continued sputter (although not as bad as before). So it's back to the dealer again.