We have a college student leaving with us that is dripping oil all over the driveway because of bad valve gasket on her 05 suzuki XL-7 allwheel drive 2.7L Auto with 204k miles on it. I was being the nice guy and offered to do the valve cover gasket for free because her dad sold her ther car and she has already spent over $1K in repairs in the last 3 months. 

That top end is a jigsaw puzzle, but I got it back together. I cleaned the the Throttle body with TB-cleaner(it sat for 24 hours before attempting to start), changed the very pitted sparkplugs, and put a new air filter in that was fully clogged. I also sprayed the sides and bottom of the engine with foaming degreaser trying to avoid any electrical- put I probably fried the O2 sensors. I did nothing with the MAF sensor.

Car runs much smoother but will shutter and shake after stopping for 5 second when in drive at any red light. 

Engine drops to 600 RPM very rough Idle after 5 seconds when stopped AFTER replacing valve head gasket and plugs.

The OBD codes pulled were P0134-O2 sensor B1, p0154- O2 sensor B2, and p0507 idle higher than projected. I cleared the codes and hoped that it would need to readjust to having mew plugs and a clean filter.  It still shutters after a week of local driving but only has the O2 sensors for codes.

I've never worked on a Suzuki before and have no idea where to start. I 'm going to order new O2 sensors for cheap on ebay to clear the codes.

Any ideas??

Thanks 

John Henderson 

Lancaster PA