Background info:

Car: 88 CRX Si

Motor: 84.5mm RS machine B20vtec + bolt-ons

-Motor has about 4k on it
-Tuned on e-c-tune


(I'm going to try to explain this to the best of my ability) For some reason my car has like a miss (or backfire, or putt, or hesitation, or jump) when I cruse around 60-70mph and also when I decelerate (sometimes). I originally got tuned this summer on my stock (240cc) injectors (+ higher fuel pressure), then when the temperature dropped (this past October), the miss came. I assumed it was due to running lean (since I was at 100% duty cycle when I got tuned). So I put the car down up until recently. I swapped in DSM injectors and changed my plugs (NGK 7 heat range), and got retuned this past week. Fixed?!? Nawwww. I just drove the car 100miles, and during my trip the miss (or whatever you want to call it) came back again (but it wasn't as bad). The car made great power when I got it tuned, so I'm happy about that. But I'm very picky when it comes to my car, so this miss is bothering the hell out of me. Plus, I need to be able to drive the car atleast 350 miles a week for class without any problems, so if anyone can help me diagnose the problem I will greatly appreciate it.

 

check and see if your tps is set right .5v closed thottle 5v WOT had a similar problem with my b20 any time i gave it up to 1/4 throttle it would cut out anything more than 1/4 it would be fine my tps wasnt set right.....

 

Thanks!

I did replace my throttle body with a 70mm one. I didn't check to see if my tps was set to the proper location. I will check that out.

 

alot of people dont realize that there tps is adjustable including me at one point
hopefully that will fix your problem let us know!

 

Checked the TPS and it's still and it was right on.


More suggestions please!!! Because this partial throttle hiccup is pissing me off since I do alot of long distance driving.

 

After reading some threads, I'm going to replace the tps. Hopefully this works.