well my idle did keep searching until i got the manual ecu in it. now it will go up to 2000 rpm as i'm slowing until i stop. i have the evap code saying its purge valve. any ideas how to fix of test it?

ok so i did do an auto to manual swap and still have the auto ecu in. now as i sit at a light or what ever it idles fine and smooth. as i'm moving and hold the clutch in it will search and as i'm slowing it speeds up the search then comes to a slow rest as i come to a compete stop. some times it wont search but most of the time it will. what can be wrong?

Sounds like an IAC issue. When my IAC was acting up it was not noticeable at idle, but if the car was in neutral and rolling to a stop the RPM's would climb and then slowly fall back to normal once the car came to a full stop.

Pull the IAC, thoroughly clean it with brake cleaner or electric motor spray, and then reinstall it. If the problem persists OHM it out and see if it is within spec.

i did clean it but i didn't ohm it. dang it that stinks. thank you i will try that then

it ohmed 48.6 so thats in limits so idk what it is now

just replace it. i had the same problem nothin

Increased idle speed while in motion is normal.

To a degree, but it shouldn't climb to more than 1100 or so if you ask me..

Some "high idle when moving" is normal with an MTX ECU. The ECU will vary the idle based on vss input. 2000RPM is a bit excessive, so you may have a small vacuum leak somewhere.

Originally posted by DarkOne
Some "high idle when moving" is normal with an MTX ECU. The ECU will vary the idle based on vss input. 2000RPM is a bit excessive, so you may have a small vacuum leak somewhere.

That, along with the evap code tells me that you may have a vac leak somewhere within the hose that goes to the LDP (evap system).

thanks guys I've checked the hoses via brake clean but no results. i will check electrical and give feed back. probably this weed end or so

Are you running a boosted 420A? Also, what year is your car?

Originally posted by Dstach
thanks guys I've checked the hoses via brake clean but no results.

Just to eliminate it from the mix (since you already have a cel), block off the line going to the Evap crap and see if it helps. Takes two seconds but it will verify quickly.

Originally posted by Dstach
well my idle did keep searching until i got the manual ecu in it. now it will go up to 2000 rpm as i'm slowing until i stop. i have the evap code saying its purge valve. any ideas how to fix of test it?

i have this excat same issue. Every sensor is new and has been replaced to make sure its not them, EVAP and EGR are removed and deleted, No vaccum leaks, only codes are for EVAP and EGR. I'm completely lost on what it could be. Its an annoying problem.

Anyone with a boosted 420A throwing an EVAP code should check both the EVAP canister behind the front bumper passenger side opening as well as the fuel vent valve located under the car in front of the gas tank.

Both of these valves are not designed to see boost and the inner diaphragms can tear over time under boosted operation. You can simply replace both EVAP items, or you can replace AND install a one way check valve in the vacuum line to prevent this from ever happening again.

I have the same problem too after installing my new header. Could it be my EGR?

doubt it. mine is blocked off. i wasn't and i had the problem. blocked it off and no change. ive had headers on since i got my car. had for a week and couldn't drive it and put headers on it so no not headers unless you changed something else

Well the o2 bung for my header interferes with my radiator fans, so currently i just have my o2 sensor ziptied up till i can get a new bung one welded in. This threw a code, but could it cause my idle to search around 2k then drop slowly?

its very possible.

anyone else have this problem with headers?? I guess its what you get when you buy the cheap eBay version haha

haha i have those. i like them tho