superfoot

I have a 93' rx7 with a new reman motor and xs engineering turbo,power fc, etc (the works)I also got the ecu tuned by a company thats on the apexi web site.when my mechanic finished the job.and he starts up the car the techomitor(sp) goes from 1000 rpm to 1500 rpm back and forth.it sounds like im signaling some one I want to race them lol.the car drives find too.its just when its idling it does this. but I do notice when I put the brake pedal on, I can feal the moving back and forth like a throbbing fealing on the brake pedal.could it be the throttle sping on the gas pedal could be sticking or something? im not sure what it would be? please help me!!!



P.S one other little question off topic:how do I get the center caps off with out damaging them?

bcty

sound like the TPS to me

superfoot

whats the TPS?

croatian 3gen

I had the same problem, but my rpm jumped from 2000 to 2600rpm...the problem was solved when I replaced the intake mainfold gasket...

I think TPS stands for throttle position sensor?

superfoot

how much does the TPS cost? thanks! im gunna look at the gaskets too now that you mentioned that.

croatian 3gen

around $150
check out www.mazdatrix.com

jspecracer7

guarantee you it's NOT the TPS or the gasket. It's the idle tuning. I have had this problem SEVERAL times with several different engine's. You have to tune the idle block of the PFC leaner than the other blocks which surround it. PM me and I might be able to explain it better.

Fumanchu

Manual Tranny TPS
http://www.mazdatrix.com/getprice.as...m=18-9110-N3A1

Auto Tranny TPS
http://www.mazdatrix.com/getprice.as...m=18-9110-N3A2

clayne

superfoot,

Why not just let it sit for 10/10/10 minutes like the PFC manual states.

jspecracer7

Okay, this is a VERY common problem with the PFC. Easiest way to fix this is:

1st: Identify which fuel block your car likes to idle in. I have my fuel correction settings so that my car idles in the -400 vacuum at 1000 rpms. Your car should be roughly the same blocks if it is streetported/exhaust ported. If you are still running the stock rpm vs. boost map, then you should be idling in blocks N2/N3 left and blocks P2/P3. One of those 4 blocks should be your target idle block.

2nd: Go to the monitor Screen and select map trace(last setting). Push the Next button on the commander. Not sure if this is correct, but there are only 6 buttons...so push each one until you get the 20 X 20 map to highlight the map in BLACK. Your target idle block should be somewhere in the middle of this. Remember which blocks are highlighted.

3rd: Go to the INJ MAP. Should be 3rd one down on the left in the SETTINGS block, with leading and trailing timing maps being 1st and 2nd. All the blocks that were highlighted in the map trace screen need to have their percentage turned up appx 2% to 3% EXCEPT for your target idle block. Wait appx 5 minutes after turning up the fuel to see if it starts to bounce faster. If it is...your on the right track. It will slowly settle down from 1800 to 1500 to 1200 and finally 1000 rpms(or whatever rpm you chose). If you blip the gas and it goes back to idling like this...no worries. It's learning and will eventually figure it out. You'll also need to do it with an electrical load on so turn on your lights or rear defroster.

Doing all of this will force your PFC into a quicker idle learn mode, and it will eventually smooth out. I had this SAME PROBLEM for over 6 months....trust me it's annoying as hell for the car to bounce from 1800~ and back down to 1000 just to go back to 1800. I could not figure this **** out for the life of me, but a random post on the NP forum fixed it! I'm not taking ANY CREDIT for this...IGY was the one who explained to me over the phone EXACTLY to do this....and after 6 months of my car idling like this...it was fixed in 10 minutes of tuning.

mad_7tist

/\ it works like a champ. noone ever belives it and is afraid to change the maps at all even though you will not harm the car.

superfoot

thanks i'll give it a shot!