I'm not sure what this falls under, but here I go. When I drive my blazer aggressively, meaning 95% throttle or more when the vehicle shifts it takes forever or it doesn't shift until I get off the throttle, and the thing well bounce off the rev limiter. Other than that I get no slippage or anything anywhere else. The only other thing is a few days ago when one of these things happened I heard some pinging and the check engine light came on. The code was for crank position sensor. I reset the code and it hasn't come back yet. Other than this the truck runs great. I'm getting about 17mpg mixed. It's a 2 door 2wd auto.

I don't even know where to start looking for this current problem

 

Is driving like that really necessary? If it's such a problem and depending on the year you could find someone with something like HPTuners and they can change the shift points and fluid line pressures which would take care of your shift problems no matter what. My best guess is a vacuum leak which is affecting shifting and causing a lean condition which can cause the ping and a timing related CEL.

 

Sometimes it is necessary to drive like that.

 

my foot knows 2 levels,mid and floored. lol


As for the issues,the crank sensor. If it comes back you have 2 sensors. one near the harmonic balancer,and one under the distributor cap.

For the shifting issues,it could be many things. Hows the fluid level while its idling hot after you have been driving it?
Test your tps sensor on the throttle body. backprobe the (think its the blue wire,i cant remember) and see if its good. it should have a clean steady increments from 0.5 to 5 volts as you steadily move the throttle linkage to wot (engine not running). if its choppy,replace it. tps is a vital part of these trannys.

clutches could be worn and slipping until you let off too.

 

I checked the fluid it was good. Thanks for the info.I'll try to source a volt meter all my tools are in California :-(

 

you can get one for like 8 bucks at walmart,or autozone etc. do it with key on to give it power. if you cant get it to backprobe just get a boxcutter and nick a tiny piece of insulation off,then tape it when done. remember,its gotta do a clean gradual climb to 5v. if its rough and random,its bad.

 

I got a video of my problem, well some of the problem.



this was probably 75% throttle. It does this every time in every gear (if I am really in the skinny pedal) otherwise it drives perfectly normal.

 

Notice how it slips right around 3K and then when it starts bouncing off the rev limiter I let off the throttle and it shifted...

 

Also, I put the transmission in 1, and it still did the same thing...

 

Anybody?