Car: 06 IX MR 14000+ miles

Mods: Basic Bolt ons: HkS Intake, HKS GTII Turbo, LICP,DP,Test Pipe,Tomei Exhaust, Walbro 255, HKS EVC-S, Boost gauge, oil Temp Gauge, Oil press Gauge

Tune: Yes

Symptoms: Last upgrade was the GTII Turbo, Got the tune after installing it, all the other mods were installed prior to the tune. Started to notice idle dipping most noticeable when coming to a stop or at a stop light. rpms would fall to around 500 and car shakes but never stalls, sometimes it would stay at 500 and wont recover until i bleep the throttle, sometimes i wait a few seconds and idle comes back up. basically there are times when it would recover and other times it would stay there. accelaration and WOT no issues as far as I can tell. I also occasionally Get the P0122 Code on random.

Remedies so far: Clean MAF with Maf Cleaner, Clean TB, ( did not replace Shaft seals) applied Dry moly on the butterfly, Replaced TPS and IACV. Went to a local mitsubishi dealer to park the IACV and adjusted the idle to 850, problem still persisted
Calibrated the tps to .69V fully closed cleared the P0122 and hasnt come back since, hopefully it fixed that problem, but idle dip still persisted. searched and searched on evom, came across the EGR valve checked the the vac hose, was surprised to find the EGR hose disconected, put it back on hoping that this would fix the issue but it did not. visually inspected all other vacuum hoses. havent done a boost leak test but i have no tester, asked the tuner and said that there was no leak before he tuned it.

I guess i have tried all these things to try and fix the issue but havent had any success so far. which brings me to this question, Has there been anybody on here who have fixed this issue or do you just live with it, cause the engine doesnt stall or anything I guess it isnt that bad of a problem but I admit to being OC when it comes to my car and i am still hoping for a fix. this idle dip only came out after the tune, so im really thinking about bringing it back to the tuner. any thoughts or other remedies would highly be appreciated. Thanks.

 

Bumping the timing at idle up to 9* and making the base idle (through ecuflash) 950 fixed my idle dip for good. Now as I come to a stop the 9* catches it before it drops down. There's a block of timing in the top lefthand corner of the map. Stock they should be all set to 6*, try changing all the 6's to 9's and watch it not dip anymore. Compensating by the above method has worked for me really well. Good luck.

 

lol this sounds way to simple for what your explaining but I had a bad idle dip like that only at stop lights sometimes it would even die.. I noticed that it only happened when my radiator fan kicked on so switched out my battery and it never happened again lol..... maybe your just thinking to hard about it? I dunno yea sounds dumb but that's what fixed mine

 

my setup is not to far off from yours either btw

 

Yeah i guess im just paranoid but im getting annoyed like hell. Glad that worked out for you. Any other thoughts?

 

I have been fighting this issue for a few months now, it's quite common on these cars and I even had a thread with a guy named shaesta. Despite the commonness of the issue there is no definitive answer to this issue because it stems from a large number of causes so for some people the tb fixes it some the oem intake tube, some the ps pump and the list goes on and on. I have tried to fix it with many of the solutions, but one of them is also the stock tune which I now have a sneaking suspicion it is. But I can tell you the newest batch of parts (new trans, exedy twin and fluidampr) have not fixed it, other than that you are just going to have to continue to investigate the specific cause on your car because it is different from car to car.

 

Maybe not what you want to hear but I have a Evo 8 ecu swapped turbo eclipse and I have the exact same problem as you described, I also have tried as odd as it sounds everything you listed under remedies (swapped TB's, dry moly, boost leak tests, clean MAF, adjust TPS) and still can't get rid of it, so to me that pinpoints the problem to the rom/tune.

Have you tried jrainwater suggestion? I'll try that and let you know if anything changes.

 

Well i havent tried what jrainwater was suggesting. Im still trying to search for other methods since the tuner is around 170 miles away. It is really a common problem with the evo especially when you search here on evom but as what stated here no real fix other people have had success while others are still searching for a solution.

 

The way I see it is most tuners tune for WOT and not so much for idle. But we are changing all these parts ie cams, intake, turbo, injectors and the list goes on. How could all these changes NOT effect idle? Of course they do. I have a question for you. Do you have an afr gauge? If so what does it read right before and during the idle dipping? Also, you might want to invest $100 on a flash cable so when you have to make minor changes you don't have to drive 170 miles. This tuning isn't rocket science or voodoo. Most ppl can figure this stuff out with a little practice.

 

Have a hard look at that intake and make sure its supported/bracketed and not vibrating causing calibration issues at the MAF-- from what I remember the hks intake was especially susceptible.

 

Yeah I can see some mechanical issues causing this too obviously but it sounds like he had already checked all that stuff out. That's why I'm looking at the tune for an answer. I tried using an aftermarket intake pipe and the car hated it (rich spikes all over the place, stalling out, massive idle dipping, untunable wot because of afr fluctuations). Once I put the stock rubber accordion intake back on all the issues went away, minus the idle dipping. A change in the tune fixed that.

 

I dont have a wideband im really contemplating on getting one soon i know its a very essential tool to have. But were you able to fix it with the tune adjustment and putting back the hard pipe on the intake or did you just revert back to stock rubber pipe? This idle dip issue only came after the car was tuned so i think a retune would might be the answer. Although i guess it might depend on the tuners ability. Bolt on mods were installed without a tune and idle was spot on, latest mod was a turbo upgrade and a tune was in order, thats when i started to notice the idle dip.

 

The stock rubber intake being put back on helped a lot. I probably could have left the hard pipe on and then rescale my maf but the stock one was an easy fix for now. The idle dipping persisted even with the stock intake though and I changed my iac and the tps and throttle body shaft seals and fpr and a ton of other stuff and it still dipped. Raising the timing at idle and setting the base idle a little higher was the only thing I have found to fix my personal issue of idle dip. You should have a wideband though. I would like to know if it swings all the way rich when you come to a stop. Mine was and that's why advancing the timing fixed the issue. It was dumping to much fuel in at decel so the extra timing burned up the fuel and kept it from bogging down and dipping. I need a full dyno tune soon but I still have a bunch of parts to install before I can do that. For yourself I would call the shop that tuned it and tell them about the idle dipping and go from there. If I can help with any questions feel free to pm me if you would like. Thanks, Jason

 

Also I forgot to mention if you just had a new turbo installed and stuff you should check for a boost leak too. You can make a boost leak tester from crap at home depot for $15. That's the first place to check for this issue imho.

 

Btw i have noticed that my walbro whine is in sync with my idle dipping it usually changes the sound i hear when the idle drops, heres how i would describe it, on a stop light i hear it go weeeeee, but right when the idle dips the sound goes wuuuuuuu everytime right on the money. Its like the pump is loosing power or something like that. Could they be related somehow. Thanks