This time, I am in need of help
#1
This time, I am in need of help
Base problem: Sputtering moderately and intermittently at peak boost
Expected solution: Fresh BR8ES plugs gapped to ~0.023
Result: No change and will try swapping stock coil packs tomorrow, but that's only an "if," and I just have two days to figure this out.
Background details:
Expected solution: Fresh BR8ES plugs gapped to ~0.023
Result: No change and will try swapping stock coil packs tomorrow, but that's only an "if," and I just have two days to figure this out.
Background details:
- Before this week, I was running 91+alky daily on a good ole Dynoflash tune from 1.5 years ago that was made for my stock VIII turbo that I have since replaced with a stock IX turbo - no other changes from that tune to 3 days ago
- Put down 324whp/348wtq on my local DynoDynamics (don't worry about the raw numbers, but rather the deltas)
- Installed FMIC, LICP, UICP, removed alky, added injectors, and retuned on E-85 at my local shop on the same dyno
- Made 327whp/343wtq with noticeably earlier spool but identical powerbands after 5k rpm or so
- Tuner said that anything over 23psi would cause it to break up. I never felt it or heard it, so I didn't know the extent, but they said turning it back to 23psi eliminated any misfiring
- I had old BR8ES plugs in there gapped to .024 or so that had not been boosted on or driven hard for 6 months. I never go 6 months with my coppers, but I hadn't been racing or driving hard due to my t-case, which is now good, so I just figured it was a simple plug swap away from running 25-26psi with ease
- Drove the entire next day (100+ miles of highway and traffic) with plenty of hard boosting through gears 2-3-4. The only symptom I had the whole time was a VERY slight hiccup when initially rolling into boost in 2nd gear on an on-ramp or something. I wouldn't feel any hiccups in 3rd or 4th, but that's somewhat expected, since when rapping through the gears, the later gears are never below 5500rpm and therefore not near peak boost
- So, that night I swapped in my fresh BR8ES plugs, but I didn't have time to gap them. I drove to get the wife some ice cream and boosted hard all the way through 2nd twice with no hiccups. On the way back, I turned up the boost one full turn (8 UNOS clicks) and boosted several times on the way home with no obvious power difference but also no sputtering or hiccups whatsoever
- Knowing I have all the equipment and software I need to log and tune, I decided to go ahead and add some things I had been neglecting while also getting some good logs to see how things were on the street vs the dyno
- I did a lot of changes to my 05 definition file, which is the funky 05 ID that is a nuisance, and I made changes to the ROM itself. I also tried out the Tephra mods by downloading the correct ROM for my ID and copying all of my tables into that ROM.
- I installed it and went for a drive - first drive of the day in the Evo. Upon boosting hard in 2nd, I got hard sputtering right at peak boost. I tried a few times, and it didn't change. My knock CEL was flashing each time, too, but I wasn't sure if it was true knock or just the misfiring. The feeling was just like when I had fouled plugs on race gas in the past (many times) and was able to boost but would have intermittent rapid fire sputtering that would release after a certain rpm when boost tapered. This felt the same.
- Just in case, I re-flashed with my base, unmolested ROM given to me by my shop. That resulted in no change - same symptoms. I then uninstalled/re-installed EcuFlash to be sure my definition file was untouched, but even when re-flashing with my base ROM after that, there was no change.
- So, I turned down the boost one full turn, since it was still up one turn from the previous night. This caused the sputtering to lessen in severity and not last as long, but it was still there.
- I then took out the plugs and gapped them to ~.023. They were closer to .026-.028 out of the box, so I hoped this would work. Unfortunately, the same problem was there - no change at all.
- Next, I will try to swap coil packs with a local Evo, but I'm skeptical that they went bad overnight. The biggest change between days was the ROM tinkering, which I know full well is not devoid of risk.
- Differences in weather between the days is minimal. It was warmer during the day when I drove a lot than today, but last night should have been just as cool (if not colder) as today was during daylight, so I don't think that was enough of a difference to throw my load off.
- Unfortunately, through all this, I haven't gotten one stinkin' log file, because my EvoScan 2.1 is logging big piles of nothingness, and I can't figure it out, so I'm running a bit blind.
Last edited by Warrtalon; Mar 9, 2008 at 11:47 PM.
#3
I have the ROM in there now that was in it when it came off the dyno and was in it all day the first day.
I can try gapping to .018, but the problem is they worked fine even at .026 yesterday and suddenly didn't work today. No change at .023 either, so that doesn't sound likely. However, if I do try plugs again, I will try 4 more brand new ones first.
I can try gapping to .018, but the problem is they worked fine even at .026 yesterday and suddenly didn't work today. No change at .023 either, so that doesn't sound likely. However, if I do try plugs again, I will try 4 more brand new ones first.
Trending Topics
#10
Account Disabled
Join Date: Mar 2008
Location: FLORIDA
Posts: 65
Likes: 0
Received 0 Likes
on
0 Posts
did the coils change anything? If new plugs dont fix the issue, could have an issue with the crank sensor or cam angle sensor.
For instance i had one car that a rat chewed a crank sensor wire and the car would start sometimes, run perfect sometimes and other times start sputtering and missfiring and sometimes not run at all had to eventualy sodder the wires back toghther. rats are drawn to warm things at night. Do you park outside by any chance.
do you have a wideband to read afrs while knocking/misfire? Alky can also add to the issue specialy if it drips into the intake piping or manifold. if it happens enough your intercooler can have a small flood when you hit full boost it can pick some up and cause sputtering due to rich afrs. hope this heps
For instance i had one car that a rat chewed a crank sensor wire and the car would start sometimes, run perfect sometimes and other times start sputtering and missfiring and sometimes not run at all had to eventualy sodder the wires back toghther. rats are drawn to warm things at night. Do you park outside by any chance.
do you have a wideband to read afrs while knocking/misfire? Alky can also add to the issue specialy if it drips into the intake piping or manifold. if it happens enough your intercooler can have a small flood when you hit full boost it can pick some up and cause sputtering due to rich afrs. hope this heps
#11
Account Disabled
Join Date: Mar 2008
Location: FLORIDA
Posts: 65
Likes: 0
Received 0 Likes
on
0 Posts
#12
warrtalon@gmail.com
Specialist:
1) Haven't changed coil packs yet - have to swap with another Evo owner tomorrow.
2) Car is in the garage at all times.
3) I have a wideband, but EvoScan isn't logging anything right now.
4) Alky is removed, and I have all new IC piping and FMIC that has never seen alky. During the 2.5 years with alky, I never had this problem.
Specialist:
1) Haven't changed coil packs yet - have to swap with another Evo owner tomorrow.
2) Car is in the garage at all times.
3) I have a wideband, but EvoScan isn't logging anything right now.
4) Alky is removed, and I have all new IC piping and FMIC that has never seen alky. During the 2.5 years with alky, I never had this problem.
Last edited by Warrtalon; Mar 10, 2008 at 12:28 AM.
#15
4200-4500rpm at around 23psi, and I am seeing glimpses of 12.2 AFRs, but that's through watching my gauges - different ones on different pulls in the same gear.
My dynograph shows 11.7-11.9 AFRs, though, so I dunno...
My dynograph shows 11.7-11.9 AFRs, though, so I dunno...
Last edited by Warrtalon; Mar 10, 2008 at 12:58 AM.