Hi Im, relativity new to rotary engines so bare with me, but I am alot more better with piston engines. So I have been driving my FD for a few months now without any probelms at all, Its just a 13b rew engine, turbo spool is good, engine runs good, seems like its running faster than it should at times though, now when I got this fd, the engine has been rebuilt already because when I looked at the engine its been painted over with yellow, which shops do to notify that it has been rebuilt. I got a egr delete on this fd, and found out that the fd has a custom down pipe.

Here is the problem, when warming up the idle is good, but when warm and idiling the rpm goes up and down, 300-400rpm, and when the car is standing in one spot and I rev it all the way to 7 and let go of the gas my car starts to choke and sometimes dies, and I have to start it up again, and also I smell alot of gas... My thoughts, 1, idle problem I think can be because of my tune, 2, how do I find out if my fd is not a stage 2 racing port or whatever they call these different stages of ports, because if my engine was stock and with my stock ecu I should not be getting any idle or running rich smells, at least im not running lean ... Does anyone have a Idea why this is going on, any ideas or info would help thanks

 

Has anyone messed with the throttle body? For reasons I cannot fathom, a common mod is to delete the cold start assist thermowax from the throttle body which causes all kinds of issue on cold start. Also make sure the dashpot is still in place. Like the thermowax, stupid people remove the dashpot and the stock ECU is unable to cope with the throttle blades snapping shut so quickly.

Adjust your TPS as per the instructions in the FSM.

There isn't really a way to tell if the enigne has been street ported without pulling the intake and exhaust manifold. You need to look into the ports and check for evidence of grinding. Unless you have a boroscope of course and can just look into the engine.

Do you have a boost gauge? If not that's the first mod you have to make. A downpipe will certainly raise the boost on an FD past what is safe on the stock ECU.

 

Thanks so much Aaron Cake, now to answer your questions.
I have never messed with the throttle body, Idk if anyone else did in the past.

And yes I do have a boost guage.

And thanks for the info, TPS is throttle something something, Ill look into that.

And what is a Dashpot and where can I locate it?

 

Another, thing... My car smells really rich, lol so rich it makes my eyes burn inside the garage. Thats tune ecu related, thats what im thinking.

 

Find out if it still has the stock ECU. If on the stock ECU, a reason it would be so rich is that an injector is sticking open or the CLT has failed and the car is stuck in cold start mode.

The dashpot is located on the front of the throttle body on the FD if I remember correctly. Round pie shaped thing with a screw on one side and a shaft on the other. Check the throttle body for coolant hoses. If there are none, then likely someone has messed with it.

 

how do i Check if its a Stock ecu from a non stock ecu, I mean the ecu looks stock to me but is there a way to clarify that?

 

A re-flashed ECU is usually labeled by whoever has done it. Other than that, you could look for any evidence the screws have been removed on the outer case...or any other evidence things have been changed. The FD cold idle was always pretty rich and fuel smell, within reason, is pretty normal. It should subside once at operating temp.

And a downpipe by itself won't cause you to overboost and is fine on the stock ECU. In fact the larger danger to an engine is if it still has the factory pre-cat.

My first recommendation is to go to the stickys in the 3rd Gen section and download a free copy of the Factory Service Manual (FSM). Info on the dashpot and alot of other trouble-shooting can be found there.

 

Should I change my pre cat? Or can I take it fully off, will it cause over boost?

 

And I checked my ecu, and it looks pretty stock to me.

 

Yes. To quality downpipe, preferably heat-coated or with sealed header-wrap.
No. Just keep the main cat and you'll be fine.

Download that Factory Service Manual and read through ALL the stickys.

 

OK I'm going to work on the FD today next change that I'll do I'll post.

 

When's the last time the spark plugs were changed they maybe wasted

 

Not that long ago maybe 4 months ago.

 

Here are some videos of my FD idle. Warm up. And after 120mph.