TonyTurboII

My car seems to studder right around there, and I was wondering if TII's get this. Ive seen a bunch of N/A people talk about it, but dont remember any TII talking about it off the top of my head. Assuming a TII can get it also, are the fixes the same? Can someone tell me the fixes? Could the ECU be faulty?

TonyTurboII

Up.

vaughnc

Yeah - it's normally a grounding harness bug where the 2nd set of injectors don't kick in @ 3500. I think rx7.com or fc3s.com has a fix posted for it with pictures.

It can also be dirty fuel injectors as well.

TonyTurboII

AHHH there is life out there. I thank you many times my friend. I wonder why FC3S.org hasnt chimed in? Eh, ill check out the site anyway.

TonyTurboII

Up. What are the fixes people? I tried a ground strap, from the intercooler bolt, to the battery, to no avail. None of the sites listed spoke of the 3800rpm hesitation.

JScott

I don't know but I wish someone would find out. I'm having the same problem. Look at my sig for my mods. None have fixed it yet. I also grnded the boost sensor and the intake. No luck. Someone suggested grounding the ECU. Mine's grounded well. They might have meant the ground wires on the ECU but there are several so ???

Scott

Keith

Yes, the TII can have this problem. However, the same symptom can appear for a whole bunch of other problems. The reason is that the point where the ECU brings on the secondary injectors and switches to internal air/fuel curves based on rpm/pressure is - you guessed it - 3800 rpm. Therefore, any problem in either circuit will cause a hesitation when switching to the other circuit. Here is a partial list of things to check.
Vacuum leak. TID leak. Air Flow Meter. Water thermo sensor. Intake air temp sensor, both in the AFM and the throttle body. Pressure/boost sensor. Line going to pressure/boost sensor, both for leaks and presence of the restrictor. Injector resistor pack, if your car has one. Secondary injector connectors. Secondary injectors themselves.

Sorry I can't be more specific, but this 3800 rpm problem is kind of a universal symptom - almost anything can cause it.

Irv, Keith's dad

Turbo FB.

What kinds of mods have you done if any?

mad_rx2

LOL@tony turbo2's pic of happy gilmore and bob barker!!!

RXster

Try here..

https://www.rx7club.com/vforums/show...threadid=17974

There is a hyperlink buried in my text to a write up on fixing the hesitation by grounding ECU wires.

Another useful link...

http://www.teamfc3s.org/info/articles/idle.html

TPDNRX7

It could be the ECU itself. Check the ECU Code, ie N331. Normaly the ones with the higher codes are the newer versions of the ECU. My Vert ran great with a N331 ecu. When that bit the dust, I replaced it with a N231. And thus developed the 3800 hesitation. So you might want to switch your ecu.

TonyTurboII

3in RB Turbo back, Walbro 255. Thats it.

TonyTurboII

How do I ground the boost sensor? Im also gonna try grounding the ECU wires. Then, if it ever arrives, put on a BAC valve.

TonyTurboII

Very useful info. Ill try get some of these tests done

TonyTurboII

Up.