FD Stalls at Stops
 

Hi everyone, I'm really new here, and I just recently purchased an FD. The previous owner of the car said it has an JDM engine swap. While driving the car, I can tell you that the car runs super strong, and it will pull and haul ass like no other. The only problem running-wise with the car is that it has really bad idle when it comes to a stop and will more than often stall. The owner said the car probably has a problem with an apex seal on the rear rotor, and since there is no grinding coming from the engine, which may come from the apex seal coming completely off and tearing up the inside of the engine, I am assuming that the apex seal may simply be stuck. However, since I am fairly new to rotary engines, I am wondering if any other problems may induce the motor to stall. Please reply with any suggestions. Thanks!

I had the same problem. Does your car have a strong exhaust smell when you first start it? I am willing to bet that your airpump just took a poop if you do! I removed mine and the exact same thing happened to me. I adjusted my idle by using a guide from one of the guys here, just do a search for airpump.

Start troubleshooting with Section F of the Factory Service Manual. You can download a copy for free from the stickied thread near the top.

Does anyone else have any other suggestions?

We can't magically solve your problems for you over the internet. You are going to have to get out the FSM and get your hands dirty. Or take the car to a shop if you aren't willing to do that.

If you suspect the motor is blown, then get a compression test and be done with it. If the motor's ok, it could be lots of things -- clutch switch, bad TPS settings, bad idle speed settings, etc.

check your idle speed control valve. the idle speed is computer controlled and should not need adjustment unless you have an aftermarket ECU. if the other owner had the engine swap there could be a chance it was left unpluged by mistake.

I had that problem with two other cars, it was a bad torque converter on both. Just snipped the wire going to the TC and worked fine. Little less mpg, but it was a cheap fix!

Does anyone know how to "unstick" stuck apex seals without having to remove the engine?

dude, you dont have a stuck apex seal, i can pretty much say that period.

Stop running round the route and do what the other guys in this thread have recommended, or else stop posting. Theres no point in asking for help if you wont follow the advice given!

Let me repeat though, you do NOT have a stuck apex seal. The engine would not "haul ass like no other" if you did. It'd be in pieces by now (grenade style)

For your info, ive got the same problem, ive rebuilt several RX7 engines myself and i have the same problem as you on my current car. I agree with everything these guys have said. My air pump took a shit of me, my TPS went bad on another car. Check them all.

Your air pump is the leftmost pulley in the engine bay nearest the air filters/box. The centre of the pulley should be spinning at idle, and stop spinning above 3k rpm. If it isnt spinning, check your AC fuse (on the US drivers side fender in a black box, just above battery), air pump relay (under the black cover at the nose of the car, held down by two 10mm bolts)and if both the fuse and the relay are in good shape, pull your multimeter out. Check you have 12v across the two terminals that the air pump plugs into. If you do, replace your air pump, if you dont, check wiring further.

If your not willing to do that, tkae it to a shop. If you cant afford to get a shop to work on your car, get rid of it.

Sounds like a TPS issue.

but can you un stick his apex seal?

Well, I took my baby to Gotham Racing today, and it turns out the motor was blown. Two faces on the rear rotor were bad.

Now, I'm having a Mazda reman engine installed in the FD.

harsh!

Hmmmm. I had this problem at one time, but all it was for me was my TPS. I set it corrctly and now it runs fine. SOrry to here it was a lot worse for you.

goodluck,
-josh

my tps was the problem bought one from fritz then it was fixed

Check your wires, plugs, clean the TB, adjust the TPS

Realy need to ask what TPS stands for and were on the car is it ? A pic on it will help to :)

TPS = throttle position sensor

It's on the firewall side of the throttle body, you can see the wiring harness for it just above the oil filter.

That sucks. I'm sorry to hear about your car.

I'm curious. How much diid you pay for this car? It's sounds like you haven't had it long at all and now the motor is dead.

Did you do any mods to it? Or did the you just get taken advantage of?

TPS stands for throttle positioning sensor. Here is some links that you may be intersted in.

goodluck,
-josh

Throttle Position Sensor ( TPS ) adjustment, fix idle / hesitation problems:
https://www.rx7club.com/3rd-generation-specific-1993-2002-16/fixed-my-idle-problems-backfiring-bucking-more-170731/
https://www.rx7club.com/showthread.p...0&highlight=tps

i was thinking the same thing, it seems like the guy kinda just passed it off "its only a bad apex seal" and with you not knowing it meant replacing the motor, i hope he didn't take you for a ride so to speak

This problem is common to many FDs and does not necessarily indicate a bad apex seal. When I bought my car, it did that but went away after cleaning the TB and adjusting the TPS. You should go get a compression test if you are worried.

I don't understand how does it possible that a blown motor that can "run super strong" just "stall at stop? (Don't get me wrong, I am not mocking you, just trying to learn here)

Clearly because he mentioned that his apex seal(s) were sticking. And he was looking for someone who can "unstick" it.
Also maybe because the user was not aware of putting the gear stick into neutral on a traffic light / stop position. Thus the stalling. Otherwise it's "hauling ass"






https://www.rx7club.com/images/smilies/fawk.gifBest thread I've read today.https://www.rx7club.com/images/smilies/fawk.gif

The seller did indicate to me that the car had a bad rear rotor, but when I drove it, it still seemed to create a lot of power. I ended up buying the FD for $8500. The car is in excellent condition, except for the engine, of course. I did get a compression test at Gotham Racing, and that is how they concluded that the rear rotor of the engine was bad. Also, since the previous owner never upgraded the ECU, I came to the conclusion that that was the problem, and the stock ECU could not keep up with the engine after all of the aftermarket modifications, thus causing it to blow. The modifications on the car include an A'PEXi N1 exhaust, A'PEXi twin intake, Koyo radiator, ACT clutch, downpipe, GReddy turbo timer, as well as many others, not all of which contribute to the destruction of the engine. Right now, however, I am still very confused as to how the car could still run with such power on one properly working rotor.