Hey guys I'm new to the forum, 2000 gmc jimmy sls owner. Quick rundown. I bought this truck from my friend it was sitting in her garage for over a year until I purchased it 2 weeks ago. I'll be very descriptive so you guys can get a clear image. The truck was running like a bag and the engine light was on. The code was bank 2 sensor 1 o2 so I switched that and it ran a lot better. I went for my emissions testing here in Ontario Canada I had 3 monitors not ready. O2 sensor heater, evap and catalyst all "not ready" also had a lending code of p0171 which is bank1 lean. Here in ontario if you fail the first 2 monitor Tests you can do a 2 step idle with the wand In your tailpipe. I passed everything with flying colours except co% limit is 0.7 my reading was 0.9. I'm by no means a mechanic but know mechanics around can give me a straight answer on what the issue is. I'd appreciate if I can get a little insight. Confused because high co means running rich and code p0171 means lean. I should also explain my exhaust has a couple holes in the y pipe. Thanks for helping guys!
2000 GMC Jimmy Emissions issues.
Molson02536
New member
Start with the simple and clean your MAF sensor and repair the leaks in your exhaust system, make sure that your engine is also running at its operating temperature of 190'F, and replace your thermostat if its not running at 190'F. keep us posted and good luck.
Molson02536
