Dude, I think your off the mark on the Cat thing. But thats just me. Describe the shaking at idle im more detail please!

 

Ok, when the car is at idle it shudders like back and forth on the motor mounts and the exhaust has bursts of excess pressure come out when it does this, like if it's cold and there is condesation comming out of the tips it will "poof" out a shot of steam for a second like this...
rrrrrr. pop, pop..rrrrrrrrr. pop rrrrrpop. And the engine rocks back and forth under 1200 rpms. There is a strange exhaust leak sound comming from where the header meets the catco cat... It soungs like it's kinda under pressure....i don't know...

 

If all the codes are cleared up, I would be tempted to set it at idle, and retune the initial idle settings to see if that clears up some of your issues. If your cat is clogged that badly, you would have NO power, anywhere. But if your itching to remove it, knock yourself out. Sounds like you want it out of there anyways.

 

My car kinda sounds like that at idle and between 1500-1000 rpm while is cold. BUT, from idle to redline it doenst sputter one bit, all the way to redline.....just goes to show how weird these engines are.

 

it's not weird at all actually - these engines are OLD. the idle sputtering can be a million different things. first, these cars do tend to have a little sputter at idle and you WILL notice it more with an aftermarket exhaust. kinda like a small misfire at idle. an idle surge from 750-900 can be a bunch of things too like a small vac leak or even just adjusting that mixture screw for idle signal. if the adjustment does nothing then the switch is bad which is fairly common. I'm putting my money on a bad idle mixture switch...also check your motor mounts, the motor shouldn't move that much and, again, these engines are old so they could be toast.

 

Did you check your cat yet? I think you really should, and get rid of it while your there if you can.

 

UPDATE- (hopefully last post on this topic) It has been quite an interesting couple weeks, It all concluded today from what i can tell. I built a code reader and it started flashing at me, the first was the thermosensor, I knew the sensor itself was good because I had jsut replaced it a few months ago, so i started poking around the connector itself, the connector had gotten a little old and brittle and a piece of it had broken off and fallen inside the plug itself, (probably from when i was replacing it last time.) Anyways I fished the small peice of plastic out of the sensor and hooked it back up PROPERLY. The car instantly ran better. Then i tried setting the tps to no avail.. so i relapced it with a j-yard one i had. Set it found the tps's g-spot and wham, It's like a brand new car. The shaking on idle is gone, the hesitation is gone and i am loving it. I reset the timing and the car runs great, The poping / "miss" on idle has decreased but IS probably due to the RB headers, catco CAT snd dual N1's for mufflers.. I really appreciate all of your help and i hope this thread helps others diagnose thier problems. If i could give one bit of advice... Make a code reader if you have an s4 this would have saved me a lot of time and money if i had just gone to radio shack first and built the reader... Thanks again..Now it's time to install the b=G springs, the struts and get her painted....

 

SWEET!

 

Hmm, this is interesting and makes me wonder about some idle problems i've had. How do you test the thermosensor to make sure it is functioning properly? And by thermosensor I assume its the water thermo sensor right?

 

Yeah, It is the sensor on the back of the water filler neck. Make sure it is plugged in and connected right. Run your codes and see what it pulls up....

good luck

trevor

 

Yeah, It is the sensor on the back of the water filler neck. Make sure it is plugged in and connected right. Run your codes and see what it pulls up....

good luck

trevor

 

congrats man, glad everything is running well for you!! you replaced enough parts to keep you trouble free for a while

 

and this is the diary of your typical RX7 owner

 

I JUST DON'T WANT IT TO END HERE?!?! I need to know more, and it was like a good book because it had a great ending!!! Awsome fix man. Makes me want to mess with my car to get it working better.