Free Stuff for Tech Support - Hesitation Problem - NOT A GROUND PROBLEM
 

This is more complicated, and to anyone that helps me figure out why my baby is not running well, I will get A Gift Certificate for 50-100.00 to some RX7 related site, or any part in that range that you would like me to buy you.

YES this is bribery plain and simple ;)

For anyone that just wants to help and doesn't need the bribe that would also be VERY much appreciated.

Ok here goes:

48k original miles 3rd Gen TT

Mods: Mid pipe, K&N Intake, 3" Exhaust all the way back, ported.

Problem: The problem is a hesitation that is NOT fuel injector specific like the ground problem it does not care what rpm I am at, but it DOES happen RIGHT when the secondaries open up, I can feel the spring in the pedal for the secondaries how its a little stiffer right when you depress at that point, and that is RIGHT where it does it, it makes the car bog to no end it will not even make power to keep its own wheight moving, its like fuel cut but with enough fuel to keep it running, but bogged.

Tested: Tested good ECU, Tested another Boost Sensor, pulled vacuum line for secondary valve, Tested ohms on TP sensor and it LOOKS ok but kind of funky sometimes can't tell if its perfectly smooth or the little bit of shake is normal its not all over the band but was hard to hold meter, lines and do throttle to check if it wigged at the secondaries opening or not, not sure if this would cause that problem or not tho.

History: Did this while blown motor before AND now with brand new motor.


Thanks in advance for the help!

Try resoldering all of the wires in the ECU?
Try WD40 on the secondary hinges?
Try ATF trick?

what ecu are you running and if stock have you upgraded the stock, how much boost are you running.

Hmmm if the fuel pump has a hi/lo output feature, make sure your getting full and correct voltage. Try changing your fuel filter (ever been done?!). If the third gens have a TPS check that for function.

I think its in the throttle position. Ill put my money on that...

If it isn't the fuel pump:

Only guessing here, but I'd be more leaning towards a spark issue.

Bad spark cable or coil/ignitor, leaking and tricking the ECU into seeing the RPM too high, or faulty coil/cable/connection that drops spark when the secondaries kick in.

The faulty coil/cable then would allow large amounts of fuel to dump into the exhaust/O2 sensor which the 'puter would then try and re-adjust the mixture, making the bogging worse.

Other than that the Fuel pump is what I would check first, unless you have access to an exhaust sniffer to see how it is really running.

By the way, it wasn't the solenoid, I bypassed it and still does it.


WTF ?????????

hesitation problems
 

I Had the same issues with my car, I have a '87 T2 half bridge proted, turbo upgrade running stock ecu n hks fcon, and MAD hesitations, i did the ground..and no go... check a lot of stuff...and finally got a new TPS and O2 sensor..and now she drives LIKE A BEAST AGAIN!

Did you test your air flow meter?

-Eric