hey how you guys doin i would really appreciate you help. i have a 86 rx7 and its hesitating at 3500 rpms and up when i punch the gas pedal but if i press the gas pedal slowly there is no problem. i tried cleaning the injectors that helped a little but the problem still continues. thanks alot

 

This is a famous problem in RX7s, I currently have the exact same problem. One theory is that the secondary injectors need to be cleaned/replaced. The second theory (and from what I've heard, more credible) is that the ECU and engine need to have better grounds. Hopefully a rotary pro can confirm this, as I'm nothing compared to these guys.

 

most likely is the grounds. Who cleaned the injectors? RC does a great job if I were you I'd have all of them cleaned, add some nice 10 gauge wire grounds to the various grounding points and make sure all are good and clean with metal to metal contact. Also how is your fuel pump and filter? Oh and make sure your coil grounds are good and you have good plugs. If all these things check out ; Is the car stock? If you are running higher than 10 psi or any exhaust or intake mods (besides just a cat-back) you could be running lean also so be careful the stock ECU does not adjust for anything it's a fixed map.

 

mop ?

 

yeah the car is still stock non turbo. where are all the grounding points i have no idea this is my first rx7 thanks alot

 

I had this same problem, But My problem was that the Cat was clogged up. I noticed it one day when I was driving on a wet road at night I saw something Glowing under the car, I pulled over and saw my cat Glowing Red. I got scared, thought my car was gonna catch on fire. heh. But I unclogged it by breaking up the filter inside. My hessitation went away. It also came back a while later and I looked at my AFM, it was corroded in the inside and wasnt opening and closing properly, I cleaned it out and it went away and never came back. But It could be other factors like what was posted above.


1) AFM door could not be opening/closing correctly.
2) Injectors
3) Fuel pump/Fuel filter
4) Cat converter.
5) Grounds
6) Fuel lines maybe clogged???

 

yeah ive heard a few people tell me about the cat problem can i run a custom exhaust no cat on the car? If i could would i loose or gain power?

 

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Before modding anything on your car, check with your local state emissions. Cause RX-7 modding is tricky especially when it comes to emissions. Lucky for me I live in a non emission state. heh. figuring you live up north and in Chi-town id check your emmision laws. if you remove cat, and get pulled over and cop checks, dunno. you might get in some serious trouble.

 

ill check into that altough i know we do have emmisions gonna have to check up on how strick they are. but if i could run without a cat though would i gain or lose power?

 

If you have any emissions at all you can't run without a cat, there is no way you can pass any sort of test without one.

If you don't have a way around the emissions test then you will have to go the more environmentally friendly route: Open up exhaust with a downpipe, cat-back and maybe a high flow cat, and a cold air intake. On the non turbos that's about all you can do.

 

where can i find a high flow cat and an affordable cat back?

 

Bonez makes a high flow cat and a dual cat system, however they are not CARB legal, so your state may or may not allow them. In CA, illegal, not sure about IL.

Popular cat backs are the Racing Beat cat back, and the N1 cat back.

 

Unholy FD3S... Shogun rocks!! He's my favorite fighter, everytime I train I think about beating him.

As for the hesitation, I did a search about 5 minutes ago because I ran into the same problem today.

The consensus within the forum is that it's a grounding issue or the 5th and 6th ports. Next would be spark plugs/wires, fuel filter, then vacuum and engine seal leaks. After those were the TPS and clogged cats.

So check up on all those and make sure they're working.

 

okay, DO a FULL tuneup(counting checking everything the fsm says in the tuneup section)(also check 5th + 6th ports). Then see if it happens again. If needed replace all vac lines and all the gaskets. Then start with your grounds, then go for cleaning fuel injectors.

goodluck

 

A quick, temporary fix is to unplug the TPS. It's just a temporary fix to prevent your engine from running too lean. It will run rich and you will trip the engine check light, but it's just temporary so you can still drive the car.

 

there are no more emissions in chicago for pre 95 cars

also, if you want an exhaust I wouldn't go over 2.25" with an NA.
if it was a turbo, I'd say go nuts! The bigger the better!

 

almost the same problem on my 90 na but at 5500rpm but it won't go away