My mods are as follows

walbro 255
1220 FIC injectors
upper and lower intercooler pipes
3.5 intercooler
3.5 SD intake pipe
Fitronic flex fuel tuning
Speed density
grimspeed boost controller
colder plugs
evo 9 bov
stock 2003 evo 8 turbo
DC sports downpipe with cat delete
greddy 3 inch catback

So I had Tom at TScomptuned do work on my car recently. Install flex fuel with Fitronic, injectors, timing belt job, remove egr, throttle body shaft seals, tune and change the car over to SD. The car made 370whp on e68. It runs good and overall I am happy. Other than this one issue he could not figure out. On cold starts the car would fire up after first crank run for 8/9 seconds then when the idle would start to lower the car won't catch it self and seem like its gonna die unless you blip the throttle which is the problem. At that point it will keep running and warm up fine. He set the idle around 1100 which it idles at that but when I am driving it will almost idle search when in neutral. It will shoot up to 1500 then go down to 1100 then go up to 1500 again. Its just odd.

I just tested the IAC by taking it out, disconnected the battery/connected it after 10 minutes then turning the key to the on position. The IAC moved in and out then vibrated which makes me think that it works fine. I still took it out and sprayed the moving part with carb cleaner then wiped it down. Have not put it back in yet since its freezing outside and its late and I can't run the car.

Any suggestions as to why it's doing that at cold start only? Thanks.

 

Dyno sheet for those that are interested

 

try increasing "IPW Multiplier vs coolant temp" in the temp range you are having trouble with.

Want to know more?

https://www.evolutionm.net/forums/ec...-tables-6.html

Note: When you increase/decrease "IPW Multiplier vs Coolant Temp" it adjusts the entire floor of the startup enrichment, so if you increase it and then can't start you might have to lower the other tables to compensate.

 

Tom already tuned the car and its not in the tune. From what I have seen on here, his work etc he is one of the go to guys in the evo community. I discussed with him and its not in the tune.

 

He "can't figure it out" but it's also somehow for sure not the tune.....? Hmmmmmm...

 

I just texted him about adjusting the tables mentioned earlier and he said adjusting them further wouldn't change it as he did it when he had the car and it didn't change the initial start up to almost dying problem. He was perplexed by the problem as well since he never seen it.

I cleaned my IAC with carb cleaner and I will put it back in tomorrow to see what it does. If it doesn't change anything I will order another one ebay/amazon replacement since its cheaper and go from there

 

I'm sure it is not in the tune, he would have sorted it out if it was. Try changing your idle control motor.

I have a similar issue, mine only does it when it sits for a few days in combination with colder weather, does not do it during the summer i.e ( combo of ambient air temperature and less density helps alleviate the problem as the air motor does not have to work at the same way to hold idle). When it does, it only does it the first time I start the car in the day after it has sad for a few days, the rest of the start up times in the same day it holds idle very well, and it does not hunt idle in any way. It is not in the tune either, the idle setup on the ecu is as it should be, and my car is heavily modified with less vacuum at idle than a stockish car with stock cams, so the slightest idle control motor hesitation affects idle for a few seconds and needs to blip the throttle a bit. I'm also not on the stock ecu, and the power fc is not famous for its idle control, the stock ecu is better at that. I've thoroughly gone through this and as I do everything on my car myself, on mine the problem lies with the idle air control motor's first slight hesitation in combination with the less vacuum at idle. The problem is so slight that there is no justification for me to get a new idle control valve.









Marios

 

If it's a bad ISCV, the $50 eBay and Amazon ones don't work.

 

I put the iac back in started the car up. Shot up to 2300 did the dying on cold start issue i bliped the throttle idled at 2000 then kept climbing what seemed like every 2 minutes by 100 rpm increments until 2600. Then climbed down to 1400 by 100 rpm every 2 minutes. Let it idle with ac on for a few minutes turned it off then went for a drive. Came back turned the car off went inside. Came back out fired it up idled right at 1100 for 30 seconds then climbed until 1400 rpm. Then as I was pulling into the garage the Service engine soon light came on.

 

The service engine soon light was a p0507 which is idle higher than expected

 

I read on a thread here that somebody had the same problem idle around 1500 or lower, switched out the pvc valve and it fixed their problem. Anybody have any other suggestions?

 

ttt