Has anyone had the hesitation starting at 3800 and continues on and off throughout the rest of the rpm band.

On warm days it seems a lot less prevalent.

edit 88 GTU it hesitates more or less depending on load

 

When mine did that it was because of the TPS. If it starts at 3800 is may have something to do with your secondaries or grounds as well.

 

I still have not checked my TPS just a little confused about the whole procedure I know how to use and own a multi-meter but I'm
still confused. (it idles super steady at 750 RPM, I dont know if it will do this and still be set wrong)

What could be wrong with the secondaries, just clogged?

 

Anyone else care to hazard a guess

 

hmm it could even be caused by the rubber grommets that the injectors sit in. These form a seal between the injector and the manifold/engine. If the car idles ok but upon building boost it starts to sputter out this could be the problem.

I would say getting a test lamp for the TPS is the easiest way to test it.

Im not sure what a 88gtu is maybe its not even turbo so that might negate the grommet theory....

 

MY car kinda does something simular. For some reason when the AC is on there is a hesitation but no AC no hesitation. Whats up with that?????

kleach

 

My car did something similar. Check to see if your fuel pump strainer is in good shape. Mine was clogged with rust, and would cause hesitations whenever I had less than half a tank of gas.

 

Checked the TPS today with a multi meter it starts at 1ohm and reads smooth up to 4.86ohm. Am I in the right ball park?

 

Do you have stock injectors in the secondaries? If larger than stock, that could be the problem. Too rich. If they are stock, then look to see if the secondary injector plugs are on good. On good???? Get a meter out and tap into the secondary wires on the ECU to see if your getting a voltage drop when your hard on the pedal and hit 35-3800 rpm. Good voltage drop from approx 12v down to 7 or 8 ? Swap primaries with the secondaries and try again. Wanna do something else? Add a extra ground to the boost sensor. Should be a pure black wire on a 88. No good? Add an extra ground wire to pins 2C, 3G, 2R, 3A on the ECU. Something simpler? Pull each plug off the ECU and reinstall the plugs. Same with the plug to the afm, boost sensor. Does this car hesitate if you ease your way past the 3800 mark???? Be judicious with the pedal and take it up to eighty mph in forth. No hesitation when doing that??? Probably is a secondary injector problem. Get the meter out and check for 12v on the secondary injector plugs when the key is on. Don't look for a ground from the ECU. Its not there at this time. Go to your solenoid resistor pack about nine inches below your air filter. Ohm out the resistors per the FUEL SECTION in the manual. Shucks, I have no idea why it hesitates. Ain't my car. EDIT: And make sure you have a good battery, good grounds from the battery to the chassis, battery to motor, motor to chassis, and all the other stuff I forgot to mention. Free manual at http://www.iluvmyrx7.com download the fuel section and all the wiring diagrams. Forget about the other nonsense in the manual.

 

HAILERS Thank you for the in depth diagnostic. I will try all of the instructions and try to give updates for anyone interested

THANKS AGAIN HAILERS

Oh yeah I'm all stock for the moment (injectors) I will not do anything till I'm running proper.

 

I've had this as an intermittant problem.. it sortof came and went with me....

make sure the TPS is OK....
ANyways, I solved mine with grounding.
I did the ECU, and grounded the boost sensor and MAF together, and to the chassis, also redid the engine-firewall ground. Cleared it all up.

 

FIXED whooo hoooo

Here is what I did, grounded ECU and boost sensor,
cleaned battery terminals

the difference was immediate, smooth all the way to the redline.

thanks to all who replied

 

In most cars when the AC is turned on it robs horsepower. However, in the Rx-7 it robs enough horsepower to actually make it noticeable. I never turn the AC on. You can tell if you are running full throttle and then switch the AC on, it feels like someone just dumped 600 pounds of gravel in your trunk.