Well here is the situation... right after i did the rod and piston install my idle totally went to the crapper.. The car trys to idle very rich "12s A/F" and when i press in the clutch the car will die. The car doesnt act this way during warm up.. the clutch has no affect on it whatsoever, but once warmed up it dies when i push it in. A/F ratios are swinging all over and idle is alot worse then before. The car didnt idle great before with the juns ont he stock ECU but it was livable and didnt die.... Chris Black at AMS dialed in the latency and scaling on the injectors when i had it up at AMS and the car ran great for the past year so i cant see it being in those.. although i did try and play with them some to no avail... Im lost as I changed absolutly nothing but the rods and pistons and this problem just pops up as soon asi start it. Now during normal highway driving or WOT the car acts 100% normal. It reponds to any changes i give it etc... I have tried many things including my friends ISC off his EVO "which is the same year and even ECU ID" even tried his O2 sensor after i spent 240$ on a new one and it didnt make a difference... Any suggestions??? I am puzzled and frustrated on this one....


The cars mod list is as follows... here are the main modifications. Wiseco 1400HD standard bore pistons, Crower I-beam rods, AMS GT35R kit, PTE 880s, 255 HP pump, AMS 3 inch turbo back, Jun 272s, super tech dual valve springs, AMS VSR intake and tuned using ECU Flash.

 

Anyone??

 

these are just tips:
vacuum leak checked?
exhaust holes checked?
harness discontinuity checked?
grounding checked?

any logs?

 

This is just a guess. Did you disconnect the battery?
If so then the injectors needed to be dialed ina bit better and the stock ecu will take some time to "correct" itself. Especially with the Jun 272's. I would also check cam timing again and confrim you are on the money.

 

Cam timing is on the $. Did a smoke test to check for vacum leaks etc. I have reset the ECU quite a few times. I tried to lower my latency voltage at 14v from .744 to .720 it seems to help a tad... but i dont think it was the answer. Maybe need to go more with em??

My mid LTFT were -5 to -6 with my scaling at 770 on the higway if i reset the ECU and take off driving when i checked them before i touched the latency value at 14v.

Here is how my injectors were scaled before i moved the 14v to .72

Scaling 770 for PTE 880cc stock regulator.

4.69V 3.624
7.03v 1.992
9.38v 1.344
11.72v .984
14.06v .744
16.41v .576
18.68v .456

 

Did your rings seat correctly? Did you do a complete break in?

 

Yes I belive the engine has seated well. No smoke and I did a quick compression test on it yesturday 175-172 across the board.

 

If WOT is good and cruise is ok but idle is horrible, I think you have a MAF issue. The new pistons changed the VE of the engine thus causing ECU miscalculations. It sounds like your injectors are scaled correctly so leave them alone for now.

What Hz, RPM, and load are you ideling in? You want your MAF Hz to be under 40 at idle. Until you can get it, you are going to have idle issues.

 

The more you reset the ecu the more the problem will persist if it is a scaling issue.
Let it learn.
Secondly again please don't take it the wrong way but did you check all the vaccum lines?
Inlcuding EGR, EGR solenoid and Evap to the rear of the car. It is the larger line in the back of the intake. Just a thought. If everything is in line I would venture to say, very confidently, that you have a scaling issue.
Also check the MAF screen.

 

New spark plugs? what kind and what gap?

 

I have a VSR intake mani so i eliminated alot of that stuff. I checked all the lines coming off it and have no leaks.

My plugs are gapped at .020 due to being on stock ignition and 26psi and pump gas. I got some blow out so had to gap them down. But they have been like that for the last 6 months with no problems. I put fresh plugs in every 2k miles as i change my oil. So these are brand new fresh plugs.


I did notice when i reset my ECU it wants to idle high and i have to manually idle it down with the screw on the TB.

I was on the phone with Chris Black a couple hours ago and he had me change some scaling in my maf to see if it would respond and it doesnt... I checked the voltage at the ECU for the O2 sensor and it seems to read right around what my ECU Scan logs are saying when i watch them in real time. Im lost....

 

I would leave the idel screw as it was stock. Or at least 6 half turns from bottoming it out.

Give the car some drive cycles and it should give you better data to work with. If you are constantly reseting the ecu you wont get acurate or enough info to coorelate with LTFT's. Drive the car and log FT's. It will help you scale things to what will be acceptable for idle and all cruise conditions.

Wish you were sloser to have a look. Sorry man.

 

Yea I wish a EVO shop was closer as well. I have said screw it and am shipping it off to my buddy Eric Jones up at AMS. I have had enough of the headache of trying to figure it out. I have tried everything from injector to maf scaling to even using another ECU!!

Ya know i have seen threads where people have had this same issue with the car dying when u push in the clutch.... But there is never an answer to what actually caused the issue!!

 

if you have the latest evoscan, you need to reset your BISS settings. Also check the operation of the ICS on the TB.

 

Ive went as far as trying another ISC and ECU off a friends car... Unless you hold the car at 2000RPM is will try to go rich and die out when u push the clutch in.