BoosTyEVO

I'v searched the idle problems on here can't find this exact problem , what happens is when driving around town the car idle is usually ok but , any time i drive highway or a long country road , then let off the gas the car will drop to 500 rpm and now often times just die on me , also sometimes the car will idle high like 1500 rpm and I will shut it off then restart and it goes back to 1100 , has a walbro fuel pump speed density evo 8 stock ecu I was wondering if this sounds like fuel pressure or idle valve any ideas

BoosTyEVO

ok I just cleaned out the throttle body with throttle body cleaner and a tooth brush and got it as good as i could put all back together and seems to have cured it however .... my idle is now about 1350 to 1450 instead of 1100 i wonder if it was so dirty the idle adjustment was off to counter it i mean it was really gunky , and I had a turbo blow a while back that fed oil up my intake so that probly aided in helping it get all gunky so may have solved the issue now i just need to adjust the idle and test again ; ]

BoosTyEVO

so i thought I had resolved it but no after cleaning the throtle body still have the issue HOWEVER i took a look at the idle control valve and noticed one of the wires to the connections was ripped apart and the previous owner did a ****ty job on it so I repaired the connection and havnt been able to test drive it long enough but it might be cured , sometimes the idle drops a bit when i come to a stop but not near as bad as before it seems but I gotta drive it more to really know if i fully fixed it here is a picture of the wire lol

http://i36.photobucket.com/albums/e3...t/IMG_2340.jpg

BoosTyEVO

still having idle problem after cruising its random it wont do it every time but when u really don't need it too , I thought it was better but then driving around town i had to put on the brakes and turn into a parking lot and the car just dies , I notice some new things , when i turn on my head lights it makes my idle drop a little bit wich may be normal , but when my radiator fan turns on the idle drops really bad like from 1100 to 500 , I checked hoses can't find any leaks , i cleaned out my throttle body , cleaned the iac and egr valve the car is running speed density and i have a really big open air filter i'm curious if the radiator fan blowing onto the air filter is causing this problem is that possible I'v heard about something like that with maf cars but not sure if it would happen with speed density , my turbo timer shows the volts so tomorrow i will watch that as i turn on my lights and as the fan turns on all input is appreciated

ProPilot04

iTrader: (11)

1. That wiring "job" is great. Haha...

2. This sounds very electrical to me. Have you checked the voltage on your alternator and battery? Are you able to restart it instantly with no issues?

tiggeryellow1

iTrader: (22)

Could be a problem with your MAP sensor. I mean I know you cleaned it but maybe that in conjunction with the electrical issue that could be coming from your altenator could be causing it. How old is your battery?

crazybaldhead

If the rad fan is causing the idle to drop, suspect that your Idle control valve or TPS is not seeing a proper ground.

An easy thing to try first is to install a grounding kit, homemade is cheapest.

If you want to check it, check your ground with a multimeter. You will see when the fans come on, the reistance increases, and then decreases with it off.

BoosTyEVO

ok battery and alternator seem to be good so must be the ground to the iac or tps or just simply they are or one of them is bad so , when testing the iac ground where exactly would i test from i have the meter and everything good to go just not sure where to check it from connect what to what lol and thanks for the input really wanna figure this out

BoosTyEVO

ok so i took the car to a electrical shop they looked over everything electrical and said its not an electrical issue they said all the grounds and everything checked out , they say its gotta be mechanical and the car is just not getting enough fuel at times , so i been watching my AEM wideband and i notice when i come to a stop i push the clutch in , and it goes all the way rich then it goes all the way lean then back to around 14.7 is that normal to go all the way lean first ? , also when my radiator fan turns on i watched the wideband and it goes all the way lean as the rpms die off so something is causing the car to not have enough fuel I'm not sure if its fuel pressure regulator or if its the IAC or dirty fuel filter , the injectors are new and it has a walbro pump in it and its tuned right hmm appreciate any input

BoosTyEVO

just checked the individual grounds from the TPS and IAC there both good , one more thing to note I have my idle screw all the way down and my idle wont go below 1100 rpm not sure if thats because of the tune or if that can help give a clue

BoosTyEVO

well i notice my idle screw was all the way tight , and its stripped so will be replacing this but ... the tune is set to idle at about 1050 i believe cause even with the screw all the way down it will idle there , so i'm thinkin maybe the biss screw or idle screw was fighting with my IAC cause i counter clock wise turned the screw to raise the idle just a tad actually was able to turn it a little with out raising the idle really and so maybe i just have to get it in the sweet spot so its in synch with the electronic side of things , i know it would be best to plug in evo scan and set the screw and then do the reset but i dont have that program nor know how to use it YET ... and so far i may have solved my issue have to drive more to really know for sure

horse-eater

Mine does this identical thing. Im pretty sure mine is in my tune, it didn't do it when it ran crazy rich. Maybe mess with the fuels in the idle range. I leaned mine out quite a bit recently and that's when it started.

BoosTyEVO

well i took it to ER and they fixed it for me turned out to be kind of a combination of things 1 hose was a little loose on my EGR valve , the fuel was a tad lean at the idle rpm level , and the TPS needed a little adjustment so fixed the hose , added some fuel , adjusted the tps and it idles great now : )