1998 Jeep Cherokee - 6cyl - 4l - how to remediate pinging - works for me
1998 Jeep Cherokee - 6cyl - 4l - how to remediate pinging - works for me
I usually baby my Jeep Cherokee when I drive. Mild throttle, shift at 2000rpm, cruise at 1500rpm
It has always seemed prone to pinging at low to mid rpms, and have run 91octane to prevent it.
So, did a search via duckduckgo, and found this article: http://www.jeepforum.com/forum/f9/4-0-pinging-335092/
I did the method of driving the car at RPMs higher than 3,200rpm. For my stock Jeep Cherokee, manual transmission, 2nd gear gives 40mph == 3,500rpm. I did a few runs at that RPM on the way to get my car smogged. Each run I did for about 30seconds to 1minute.
Car passed smog test with flying colors.
Driving back home from the smog test, did a few 1/2 throttle pulls from a red light, shifting like I usually do (2000rpm shift, 1,500rpm cruise). Engine feels strong, no ping.
IT WORKED. IT TOTALLY WORKED. *happy happy happy*
Now I just need to remember to do this high RPM technique when I sense the engine has built up carbon, again, and has started to ping at low RPM, again.