Hello all, I bought a 1987 RX7 from a local junkyard. It sat for awhile, before I aquired it, and now after some work I have got it to run, and pretty well at that. but it wont idle, why? It also hits a flat spot in the RPM at about 4000rpm.... Could it be a plugged injector? Anything I should look for? This is my first attemp at a rotory engine... any help would kick a$$

 

It also hits a flat spot in the RPM at about 4000rpm....


Maybe you could get a little more detailed.


but it wont idle, why


Could be lots of things.

BAC

Vacuum leak

TPS

Etc etc....

All of the above can affect idle and drivability to certian degrees depending upon how serriously they're malfunctioning or maltuned. And that's just the short list.

Maybe you should describe your symptoms much more indepth?

 

Flat spot at approx 4000 is a bad sign of the 3800 stumble... Search my man!

 

yeah search is your best friend here, some get upset if you dont use it enough .

4k flat spot, typically an ECU grounding issue, and there is a writeup on how to do that in the archives.

TPS likely suspect on your idle, in addition to the list provided above, check out 'variable resistor' in a search, as that may also be culprit.

 

Alright, here is my best shot at explaining what is wrong.

Feels week under accelleration, not dead, but not up to par. Has a flat spot under hard acc. around 4,000rpm. Cleaned the BAC today, made it start easier and run smoother below 1,500 rpm, but still choppy under that. Does not Idle, dont know why, dont know what TPS is, dont know where to ground wires. Where would a vaccum leak occure that would stop idle? Thanks and sorry for the dumb questions, that is what come from a newbie though!

 

plugged cats?

 

TPS= Throttle Position Sensor. Check it out in the FSM under Fuel & Emissions:

>http://www.teamfc3s.org/main/factory_service_manual

*One of the best sources for ECU grounding: >http://wozzoo.tripod.com/index.htm
look under 'Tech' then, ECU.