- Aug 2, 2014
- 90
A while back I had 2 ignition coils go bad, not at the same time. Replaced one and still had a misfire. Thought it was the replacement that was bad but it was a different one. '02 Envoy SLT with 146,000 miles. These were original coils. During this I changed the plugs. About 5 years ago I had installed NGK's and all worked well. Used them again this time. I also removed the throttle body and cleaned it thoroughly. Air filter looks fairly clean.
Now the curious part is that before I had the coil problems I was averaging about 17.5 l/100km (13.8 mpg(us). While I was working on the misfire problem the gas mileage got as bad as 25 l/100 km.
Now the truck is running very well, nice and smooth idle and acceleration but my gas mileage is currently averaging 10.2 mpg (US). I only drive this back and forth to work (about 2 miles) downhill one way and uphill the other. Couple trips every now and then that get speeds up to 40 or 50 mph.
Is there anything I'm missing that could be cleaned or adjusted that may have become fouled during the misfire episode?
Now the curious part is that before I had the coil problems I was averaging about 17.5 l/100km (13.8 mpg(us). While I was working on the misfire problem the gas mileage got as bad as 25 l/100 km.
Now the truck is running very well, nice and smooth idle and acceleration but my gas mileage is currently averaging 10.2 mpg (US). I only drive this back and forth to work (about 2 miles) downhill one way and uphill the other. Couple trips every now and then that get speeds up to 40 or 50 mph.
Is there anything I'm missing that could be cleaned or adjusted that may have become fouled during the misfire episode?
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