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Old 03-21-14, 08:54 PM   #1
markusrose
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Default Stumble fix mod

Ahh yes the good old stumble fix...once again

Ok so the reasoning for me to bring this up is that im looking...more or less for a quicker cheaper fix. (leased so definitely cannot tune)

I know I can do the fuel line extension, but from my understanding I will need some sort of tune with this route?

I also managed to stumble upon someone using the GD FPR, they say it helps resolve the problem but I couldn't find a lot of information on it (does it work, tuning needed?). So if someone could shed some information on this it would be great help

And lastly IAP makes a "GR stumble fuel kit fix" for $199 which doesn't bother me, but if one of the above is going to do the trick then ill just go with that.

Have any of you guys done any of these? what were your thoughts?

These are pretty much my only three options when it comes to an easy/cheap fix that can be returned to stock in a hurry if something were to go wrong.

Thanks in advance guys any help at all is definitely appreciated.
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Old 03-22-14, 01:36 AM   #2
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Default Re: Stumble fix mod

I chased the dreaded stumble for over a year with two different tuners. I tried the fuel line extension, changing to the GD regulator set-up, an aftermarket regulator, and at least half a dozen tuning tweaks along the way to try to get rid of it. Replacing the fuel rails was what solved it 100%.

Essentially, changing the rails treated the disease, everything else was treating the symptoms. Other people may have had better luck with the cheaper changes, but for my car none of them worked out.
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Old 03-22-14, 01:41 AM   #3
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Default Re: Stumble fix mod

Personally, I've done the fuel extension mod and it works very well. If you have an accessport and ots map, you can ask Cobb for AccessTuner for free and modify the ECU yourself. It's very easy and only involves changing 2 parameters. As for the latter 2 options, I don't have experience with them and cannot say much.
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Old 03-22-14, 04:05 AM   #4
markusrose
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Default Re: Stumble fix mod

did you guys run any of these remedies at all before adjusting your maps, what results were yielded?

What are the dangers associated with me not tuning after I do the mods?

I apologize if I was unclear in the previous post, I am on a lease and cannot tune until my buyout period arrives. This is more or less for me to tame the problem down, so if something were to go bad with my motor I could easily just return it back to the way it was.

Thanks for the input, good information so far!
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Old 03-22-14, 06:55 AM   #5
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Default Re: Stumble fix mod

I just ran 3' of Fuel Injector Hose and called it a day. $10 and I was in business. No tune, no more stumble except if I recently pulled the battery which resets the ECU. After a couple drive cycles it seems to smooth itself out.

Word of advice: use a drop of blue service removable loctite on the hose clamp screw, otherwise it may back out over time.
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Old 03-22-14, 08:58 AM   #6
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Default Re: Stumble fix mod

Quote:
Originally Posted by grrSTI View Post
I just ran 3' of Fuel Injector Hose and called it a day. $10 and I was in business. No tune, no more stumble except if I recently pulled the battery which resets the ECU. After a couple drive cycles it seems to smooth itself out.

Word of advice: use a drop of blue service removable loctite on the hose clamp screw, otherwise it may back out over time.

did you use the same method and hose used in this writeup: https://www.iwsti.com/forums/how-inst...e-fix-mod.html
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Old 03-22-14, 08:59 AM   #7
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Default Re: Stumble fix mod

edit*
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Old 03-22-14, 09:40 AM   #8
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Default Re: Stumble fix mod

Yes, just make sure you get injector hose and injector hose clamps.
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Old 03-22-14, 01:17 PM   #9
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Default Re: Stumble fix mod

$25.00 later..got the hose and clamps!

now all i need is for spring to come, and for the snow to melt so i can get the whip back on the road. Ill be dropping a post once i get a few runs in on it.

Thanks for the help once again boys, If theres any other tips, tricks, or wisdom to be given just list them here for some other noob such as myself!
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Old 03-22-14, 01:28 PM   #10
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Default Re: Stumble fix mod

The fuel line mod doesn't require a tune. Adjusting the tables will just help smooth even more, but not necessary to run the car safely.
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