i was doing some logging the other night. 2002 transam ws6, longtubes and lid. Car was pulling great, i was making some minor timing adjustments. I noticed in 2 out of 11 logs made. the grm/cyl spiked to 300 and pulled like 6 degrees of timing randomly. When it never goes over like 35grm/cyl. it just randomly jumped up for like 1500rpm pulled all that timing. Any ideas? im going to check for loose pins in the wires. Ill probably end up getting a maf. anyone else experienced this?

 

Maybe the Maf is the cause. You can unplug it and check to see if it changes, Normally that is the problem.

 

thanks for your reply. Its pretty random thatd id catch something so intermittant during a log over like 25 seconds, but im glad i did. I know mercedes benz maf's go bad all the time. Just wasn't sure if they were fairly common on gm's. thank you

 

If you look at that point and see that other values go crazy as well, then it was likely some sort of communications glitch. A good indicator is if your temps change rapidly when they did not in actuality.