replaced coils and still really rough idle
 

ok i have a 2004 MT w/CAI and exotic speed exhaust
never had anything but 93 octane in it and mobile clean 5000 5-20.
hard driven every couple days

so i have a problem with a good start but hard as hell idle ( sounds like a old chevy 350 with a cam the size of a grape fruit )....i do a couple days of research and figure its the coils so i buy new airtex ones and put them in this morning.....start the car up and to no surprise SHIT stilll rough idle. i then proceed to look for vacume leaks and cant find anything but i do notice that the air pump is on so just out of curiousness i unplug it and the car about cuts of and then idles fine. i let it warm up after that and take it for a drive, i get to a stop light and the idle drops to about 500-800 rpm but jumps back up. i leave the light and i notice that the car does pull a little better and when i did a uturn u come back home it kicked out a lil better so i know my coils were goin bad........so i get back home after a good bit of "high reving" let the car cool down and start it again and it still rough idle with and without air pump connected ANY IDEAS.....MY BABYS GETTING A TURBO IN THE NEXT MONTH OR 2 AND I WANT HER UP AND RUNING GOOD BEFORE SURGERY LOL

1. airtex coils? need more info plz
2. you're going turbo soon: what does your compression look like?
3. did you rest your ECU?
4. have you checked / cleaned the maf?

^ +1

Also would not hurt to check your plugs and spark plug wires :)

A lot of things will cause a bad idle - you just have to eliminate them one at a time .

Coils was a good move , how about the plugs and leads ?
MAF dirty
vac leaks
02 sensor faulty
low compression

1. airtex coils=http://www.rockauto.com/catalog/raframecatalog.php?carcode=1416844&parttype=7060&a =FRc1416844k935266

2. compression will be tested within the week, last minute typ of person

3.yes, but not sure if it was long enough.....it was about 20 mins

4.checked it and it lookes fine but how should i clean it if i do? also the intake manifold right inside the butterfly is caked with black suet

make sure you clean it up around the throttle plate ....

behind it also? in front is clean, behind it is BAD!

lmao at ur sig brettus

well if the throttle plate is gunked up it may affect your idle - behind it not so much .
Sounds like you need a catch can .............

catch can= check! got one comin........btw the turbo kits im debating on are the FSR and esmeril, incase it was a upcoming question for anybody

You will love the whole quote then - have a read .............


https://www.rx8club.com/showpost.php...2&postcount=69

wow , i fixed my fucking problem and a dumb bitch backed into my damn car ....wtf......and she said she cant find her insurance....i think she doesnt have any

btw whole quote was great lol and my problem the whole time was the screen in the aem cold air pipe was sittin against my MAF....go fucking figure....welll atleast i have new coils

bought sum sea foam for the first time and it didnt hurt either....smoothed it out a lil more