tsherriff

My Evo IX MR mods:

Injen Intake w/ uicp
Speed Source licp
Ported exhaust manifold (gasket matched)
Invidia o2 housing
Espilar 3" cat back w/ testpipe and o2 simulator
Sun Auto Hyperforce ignition
Sun Auto grounding straps
Walbro 255lb fuel pump
GSC S1 cams
ARP head studs
Greddy fmic
Greddy Profec B Spec II ebc
Greddy turbo timer
AEM Uego wideband
Greddy boost and egt gauges
ACT HDSS Clutch with ACT light flywheel
Stock IX turbo
Custom dyno tuning by AMS in Gaithersburg, MD

*Currently AWHP is limited to 18psi for a safer tune: 339hp/329 tq

I use to use octane booster in my vehicle until 6 months ago, but after killing two AEM Uego sensors I realized that the octane booster was the cause of this. The reason why I'm asking for help is because in the last two trips to the dyno, my A/F goes lean (@ 21 psi, 11.9-12.0, knock count is 4-6) when I hit peak torque, no matter how much fuel I add and how much I lower timing; then drops back down to 11.0-11.5 till 7,500 rpm. I replaced the walbro pump, plugs, tried another MAF and IX ECU, boost leak test (none). None of these had any affect. I've come to realize that most likely the fuel injectors (one or all of them) have been damaged from the use of the octane booster and fuel system cleans (from Mitsubishi and Firestone). I'm trying to get past this problem so I can finally turn the boost up past 21 and increase my timing.

My best guess is that my injectors are messed up so I need to order new ones, and while I'm at it, might as well get 680s to be safe for C16 and much higher boost levels at the track.

Have any of you had a similar issue, and if so, what did you do to fix the problem?

Mr. Evo IX

iTrader: (5)

I've had injector problems with my IX. I run 12.2 AFR at peak load @23.5-25 (varies some based on temp) psi on 4* of timing, after peak load I gradually richen to 11.1 at redline. What kind of timing are you trying to run? Can you post a log?

Here's a thread that has most of my injector woes in it. I was getting a CEL and was not getting knock. What do your fuel trims look like? Last post on this page.

https://www.evolutionm.net/forums/sh...=335340&page=2

https://www.evolutionm.net/forums/sh...=335340&page=2

tsherriff

I don't have the graph or log since I was doing my dyno tuning in DC. They are using ECU Flash software. I started noticing this problem on my AEM Uego wideband last October, but never really knew what was causing the isssue. All I saw was a 12.0 for a millisecond on my a/f guage and just figured it was normal. When I went to reflash my car it was apparant that someting was wrong. Getting to much knock and leaning out only at peak torque. We just narrowed it down to the injectors. I hope this is the issue, since I was using octane booster and fuel system cleaners it might have screwed up the injectors.

Trying to run 19 degrees advance, which is normal with every other EVO IX that they have tuned here they said. I have turned it down to 9-11 degrees advance and still getting high AFRs (11.7-11.9) with knock.

I'll check out your threads. Thank you.

travman

iTrader: (26)

What is your timing at peak torque? Most IX's seem to like 4-5 degrees on pump. Your afr is fine - its probably to much timing (guessing since you have no logs).

Also you were trying to run 19* up top on a IX on pump gas? That is a lot for a IX usually they don't like the timing that can be run on a evo VIII. Anything over 12-13 by red line gets me consistent knock counts.

That afr is fine - I shoot for 11.8-12.0 afr across the board.

- Have you ever checked for boost leaks? boost leaks can cause the turbo to over work which can cause knock issues.

mplspilot

iTrader: (7)

19* on a IX? What shop is that??

Mr. Evo IX

iTrader: (5)

If your tuner is trying to run 19* or even 9-11* degrees of advance at peak torque that would be your problem right there. Even at low boost that's excessive timing. The fact that you mentioned 19* leads me to believe that those numbers are referring to timing up top but 19* is still alot for up top and 19* @ peak torque on a IX could cause damage.

18-21 psi of boost will normally run in the 220 - 240 load columns of your timing map unless your MAF is incorrectly scaled for your intake. Here is the timing I run in my 220 and 240 columns (18-21psi). I suggest taking it back to the tuner for him to take care of the knock.


RPM 220 240
0 -10 -10
500 -10 -10
750 -10 -10
1000 -10 -10
1250 -10 -10
1500 4 3
1750 5 4
2000 5 4
2500 5 5
3000 6 5
3500 6 5
4000 6 6
4500 7 6
5000 8 7
5500 9 8
6000 10 9
6500 11 10
7000 13 11
7500 15 13
11000 16 15

tsherriff

I did a boost leak check and there were no leaks. Also, this max afr happens only at peak torque, then drops down to 110-11.7 till red line. I try to run higher boost (21-22) but the knock count jumps up and then timing begins to get pulled. They were trying to set timing 19 up top, but had to set it below 10 get a safer tune with less knock and afr. I just cant understand why i cannot bring boost up beyond 18. I figure i am maxing my injetors out or one of them is not working properly to give me such high afrs with low boost.

cssaddictm4

iTrader: (13)

4* is way too low, 19* is too high.. sweet spot is usually around 6-8* at peak torque and 14*ish to redline with 11.0-11.3 AFRs.

tsherriff

Has anyone had any issues with octane booster or fuel cleaning (iv hook up to intake vacuum) cause injector problems?

Mr. Evo IX

iTrader: (5)

I didnt suggest that the OP needed to run 4* - I posted appropriate 18-21psi ignition timing that would likely work and not knock with his current AFR, I was just using that as an example to show how out of window 19* is. And FYI 4* is just right for my 25psi tune on 93 octane.

cssaddictm4

iTrader: (13)

What are your AFRs @ 25PSI at peak torque? Do you monitor EGTs?

C6C6CH3vo

iTrader: (9)

19* at peak VE is for those times where you want the engine crank spinning CCW . I suppose you can richen it up to about 9 afr to keep knock sum below 20 counts, but instead of knocking to death the head would melt.


12.0 is rich.

egt is a useless tool for this application

Anyhow, there are tons of things that can cause a WB to read lean of target and not respond.

Any log files?

tsherriff

I'm running as rich as I can possibly go, and it is still hitting 12.0 afr with only 18-19 psi. Something has to be wrong with the injectors then , right?

recompile

iTrader: (38)

Is Lean Spool enabled or disabled?

I doubt you have an injector problem, because max airflow is at the top of the RPM range, where the injectors do much more work