2G Hesitation/Bog/Idle's-Cruises Lean

[Chrispy0530]

Tried searching and couldn't find the answer I was looking for to solve my problem.

So I've had this problem for a couple days now, were the car will pretty much have a slight miss-fire/bog/backfire either under idle, or cruising. I for the life of me cannot figure out what it may be. Car was completely fine just until a couple days ago.

Setup;

• Evo III 16G
• 1250cc FIC Bluemax Injectors (Running Pump Gas Currently, never done E85)
• AEM Wideband UEGO
• Speed Density (ECMlink Package) // Speed Density Plug & Play Cable
• 255LPH Fuel Pump

So far I have tried,

-Fixing a small exhaust leak I had on my 02 Housing
-Trying to simulate to Wideband 02, and try front 02, same result
-Swapped Coil Pack, Plugs (Gapped at .23), Spark Plug Wires, and TPU.
-Swapped TPS
-Checked to make sure timing was correct, and is on time.
-Compression Check
-Replaced Fuel Filter
-Replaced FPR
-Unplugged battery to let ECU reset, and no luck.

The car only does it while idling, or while cruising. It's worse when the car is first warming up, bogs and backfires quite a bit. Sometimes, when driving the car will even shut off. Not often, but it's happened twice. If I go into boost, the car pulls awesome however and has no problem.

I'll go ahead and post up a log for those who have ECMlink.



*Note**
I did notice when locking the car in open loop, the misfire almost completely stops, but obviously the car runs richer in general.

 

[Chrispy0530]

Yikes.. 92 views and not one reply.

Anyway, car is still having the same problem, but had a new symptom that popped in as well. While driving around, the car pretty much lost a huge amount of power, started really sputtering up, wideband when completely lean at all times passed 17(18ish on ECMlink log). Best way I could describe it was it sounding a bit like a Subaru. Very similar sound to it.

Would shut the car off, and would be fine for about 15 seconds then start doing it again. When I arrived to a friends house, it stopped doing it, go figure.

I'm at a real loss here. Any help is appreciated.

 

[Chrispy0530]

Maybe a video will help.

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Subaru like misfire seems to have went away, though with the way the car is acting, can pretty much come on at anytime. You can hear how the car sounds "cam'ed", but really are misfires every time it has that loopy idle.

Cams are stock.

 

[jigga0282]

I have the same issue with FIC 1450s. The bigger injectors get harder to tune for idle/cruising since cruising is about the same as idling. NGk BPR7s or colder for plugs. They can also foul out at wot so pull them to see if your rich at that.

 

[MHuddy1213]

random question here but have you checked your voltage?

 

[1Gina2G]

Hey there from miami! I'm just a state away at the bottom of SC. Anyways,

I know it can take some time for the real info to arrive, I'm deffinatley no wiseman but I'm curious myself so I'd like to ask a few things, maybe we can figure this thing out.

-I know this is a repeative question for anything really but it wasn't on the list -- did you do a boost leak test?

-you mentioned you tried installing a new TPS, did you also adjust the sensor's postion itself? what about before? If so, which method did you use?

-just to confirm, are you using a 1G cam angle sensor (Adjustable) - if so has it been adjusted with a timing light? (what setup are you, 1G,2G?)

-noticed you have a 255 pump, and that you mentioned you 'replaced the FPR' does that mean you're using stock fuel regulators? If so you should have an adustable regualator instead.

-speaking of gas, do you have any way of measuring fuel pressure? I personally dislike the regular method of checking the fuel pressure with these cars since there's no 'easy port on the fuel rail, like other vehicles' so I thought an electric guage was worth every cent.

-last but not least, when was the last time you messed with your BISS screw on the throttle body, or have you ever? how old is the TB, my last really weird idle problem was fixed by properly adjusting the TPS voltage/postion and by screwing the BISS ALL the way in till it stops (not tightly of course) and backing out no more than 2 entire revolutions, I used a flat-tip screwdriver to reference the screws postion by matching the flatside if you can imagine.



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[Chrispy0530]

Thanks for the replies.

I have the same issue with FIC 1450s. The bigger injectors get harder to tune for idle/cruising since cruising is about the same as idling. NGk BPR7s or colder for plugs. They can also foul out at wot so pull them to see if your rich at that.

Yeah, I hear you. Though, the injectors were pretty much dialed in perfectly, and the car drove perfect for a month. This just happened out of no where.

I pulled the plugs as well, and they looked fine. Running BR7ES.

random question here but have you checked your voltage?

Voltage reads at 14.2-13.9. Can even see it on ECMlink log.

-I know this is a repeative question for anything really but it wasn't on the list -- did you do a boost leak test?

Yes, have done a boost leak test and have a small leak on my actual FMIC. However, I'm on Speed Density. So even if I had a blown coupler, the car would not run as it is now due to a boost leak.

-you mentioned you tried installing a new TPS, did you also adjust the sensor's postion itself? what about before? If so, which method did you use?

dsmlinktpsadjustment [ECMTuning - wiki]

-just to confirm, are you using a 1G cam angle sensor (Adjustable) - if so has it been adjusted with a timing light? (what setup are you, 1G,2G?)

7-Bolt Evo 3 Longblock, just with a 1G CAS. Yes, as been adjusted with a timing light.

-noticed you have a 255 pump, and that you mentioned you 'replaced the FPR' does that mean you're using stock fuel regulators? If so you should have an adustable regualator instead.

This I know, however, I have many local friends who pushed cars way passed my limits with a stock FPR. And on E85. A AFPR will be purchased, but not until I figure out what's going on now first. Car was driving perfectly fine for a month, and have friends still rocking a stock FPR on 400whp setup on E85 for years. Highly doubt this is what's causing my car to behave so odd.

-speaking of gas, do you have any way of measuring fuel pressure? I personally dislike the regular method of checking the fuel pressure with these cars since there's no 'easy port on the fuel rail, like other vehicles' so I thought an electric guage was worth every cent.

Hmm, at the moment I don't.

-last but not least, when was the last time you messed with your BISS screw on the throttle body, or have you ever? how old is the TB, my last really weird idle problem was fixed by properly adjusting the TPS voltage/postion and by screwing the BISS ALL the way in till it stops (not tightly of course) and backing out no more than 2 entire revolutions, I used a flat-tip screwdriver to reference the screws postion by matching the flatside if you can imagine.

TB was rebuilt a year ago.


Thanks so much for the input so far guys.. Please feel free to throw more suggestions. Dying to drive it again.

 

[1Gina2G]

Well my TB is also rebuilt, but the BISS screw was not asjusted properly. Really easy to check, even though there's a more precise way to set the BISS.

where is your front 02 sensor located, have you checked 02 voltage? I actually need to check my voltage tomorow just to be sure.

 

[Chrispy0530]

BISS screw is adjusted properly again, and no luck. BISS screw is only a few months old as well, as my other one had grown brittle and dried up pretty bad.

Car is set to simulate off my wideband, which is located on the 02 housing. As shown on the log I posted, the voltage cycle's fine.

 

[Deadspool]

I had something like this happen recently, one of my injector clips backed off slightly, If i were to take a guess, it was half firing the injector. Pushed it back down, Good to go.

 

[mchustle]

Did the op figure this out I'm having a very similar problem?

 

[elguareali]

I'm having The same Problem with my gsx (evo 8 ECU) did you figure out what was The Problem? How did you solve it? Thanks for your reply

It's driving me crazy

 

[DiyDsmGuy]

Did anyone figure this out my gsx is doing this same thing? Car sounds and runs exactly as the posted video up top.

 

[Vegas Smith]

Did anyone figure this out my gsx is doing this same thing? Car sounds and runs exactly as the posted video up top.

Start a new thread with your mod list and a log if you have one.