I have a 88 10th ae with s5 rotors and fresh rebuild. I am also running 4x720cc injectors, cold air, 3 inch downpipe, and RB catback. oh and a chromoly flywheel with rtek 1.8 ecu chip. In 3rd, 4th, and 5th gear slowly accelerating past 3500 I have a jerky hesitation. Fresh injectors an good grounds. TPS perhaps?? or timing a little retarded?? Please help!! could I be running rich or lean??? aaah!

 

Could be TPS. Is it only at a point around 3500RPM or is it constant as you increase engine speed? If constant, I'd still suspect injector grounds. If not, possibly timing, but not because of the ECU. Also, Rtek has had in the past issues with hesitation when switching on the secondary injectors, which is relatively close to 3500RPM, you could shoot them an email and inquire or ask on their forum section here.

 

thanks a bunch for the advice and tips on what to check. With my rtek the secondaries kick in at 3300.. also it isn't constant if you slowly accelerate past it then there isn't a hesitation. It's only pronounced when in higher gears when your cruising into that area and not necessarily accelerating hard. My friend said it's TPS because he showed me how to set the timing. I'm going to check my grounds and potentially adjust the tps on monday. thanks again for the feedback

 

im having that same issue with my na s4. Tried the tester light method and was not responding the way the lamps usually do as you turn the tps adjusting screw there is a point where either one light or both lights are on and that point seemed vague on my car. still fun up untill 3.5k

 

Try adjusting the Green/Red wire of the TPS to 1 volt when the engine is fully warmed up. I've read where the tester light method can damage the ECU.

 

It's actually 3500 RPM with the Rtek 1.8 (http://www.pocketlogger.com/index.ph...age=1&ecu=S4T2). TPS and grounds would be worth checking out. Some have had success in eliminating the dreaded '3800 RPM hesitation' by re-grounding the ECU. Mine actually went away after I converted my car to turbo, so it's hard for me to say what actually fixed it for me. My grounds didn't change, but every sensor and the ECU did.