Help needed please... Ve sportwagon with a stutter

Hi All

I really need some help before I end up doing something stupid like trading my vehicle or burning it!!
VE Sportwagon M6 - Mafless tune - OTR - HSV headers and mufflers - 45,000 klms on it.

About 4 months ago I noticed I was having a shudder/stutter sort of feel when accelerating. Took it to get looked at by my tuner, and as I had added an auxiliary fuel filter pre inlet manifold (to stop a fuel line harmonic noise) they pulled this and noticed it had water in it... yep copped some water in my fuel tank compliments Caltex!
Anyway it hadnt broken down as such as this filter was stopping the water entering my injectors.

So many tanks of petrol later - a few with metho and a few with Fuel Doctor we believe we have all water out of tank - BUT I still have a "stutter" (for want of a better descriptive word) going on on normal drive accelerations (you don't seem to notice it if driving hard at all).
Take it back and get the tune checked - all looks good on the laptop whilst driving... fiddle with a couple of things but nothing glaringly obvious stands out. Drive again and it is still there.
Go back and change plugs and leads... still there!!!!

To describe the problem:
I figured out tonight driving that in 2nd, 3rd, 4th or 5th when you drive thru the 2100 - 2500 rev range it gets a stutter or jumpy feel to the acceleration. If you drive along and hold it around that rev range you can feel it in whatever gear it is in. As you drive past that rev range it clears up and drives fine!

What could cause this??

Tuners next step is to set it back to standard tune and intake and see if the problem exists still... maybe the easiest at this stage - but to me if it so easy to replicate at that rev range it cant be anything to do with the water it had in the tank (?)
Maybe the injectors? But wouldnt it be more speratic instead or being in a certain rev range?

Any help would be heaps appreciated...

Have you continued checking the filter for water or just presuming the water is gone?

yep we continued for those tanks emptying it and cleaning this filter.
Then we took this filter off completely (and is still off now) to let the little bit that may have been left behind to go thru system with aid of the "Fuel Doctor" product etc.

But if it was still water, you would think it be more "hit n miss" as to when it "played up"? Not as clear as between 2100-2500rpm??

Need much more info. I quick description of how the car feels won't help much. A video of the issue ( if possible ) or a data log of the event would be better.

I'd hazard a guess that it's fuel though, if it's not still contaminated, it'll be delivery or mixtures. It's a very rough guess though.

Simon.

sounds like is load relevant. If you have a mate with same car might be an idea to swap injectors over and see if it makes a diff as injectors do not like water

Thanks for replies guys.
I think would be pretty hard to document on video as it is not a violent shake.
I am hoping it is still not fuel, Caltex have denied being responsible for the fuel contamination, even though the 7 tanks leading up to discovering the water where all from one of their servos near my home.
So it would be probably quiet expensive for me to get fuel tank out and cleaned etc.

I have just over a month left of my warranty and have had it to Holden to check. They recognised the problem, checked fuel pressure etc which is all OK. They said it is tune related and to return the car to stock tune and they would investigate further. Should I use this as my next option? Maybe they might injectors are screwed?

As much as people tend to hate Holden service, I'd agree with them that it's tune related. This is what I'd do.....

1. Reset the fuel trim data in the ECM either using a command from the tuning software or an ECM reset ( remove power ). Do this when the car is exhibiting the issue ( IE, if it's worse when the car is cold, do it then, otherwise do it when the car is hot ). Then go out and see if it feels any different. If the problem changes, then it's learnt fueling data (LTFT) and may be related to the bad fuel you had.
2. Log the car during the issue and check for any changes that are occurring in the log data. It'll take some time to separate symptom for cause, but it should be able to be done.
3. Return the car to stock and see what happens.

To be really honest, I don't think its Holden fault and I'd be pretty pleased that they are willing to look at it given the mods done. You must have a good relationship with the dealership :thumbsup:

Simon.

Thanks swing for your help
Pretty sure all fault codes have been looked at but as you say Holden have been very good at being willing to look at my vehicle even after it has been edited.
I have it booked for Tuesday to return to stock and then booked for Monday week for Holden to look for any fault ( if there still is one after tune is deleted)
I really am not mechanically minded so hopefully it is an easy fix whatever it is

what the jewl in the rough said .
If holden are willing to have a look with the tune back to stock , jump on it .

Each time I've had a stutter in the same manner as you've described, it's been because one of the spark plugs has cracked

Changed plugs n leads 2 days ago... Made no difference unfortunately.

Try the ECM reset, you might be surprised.....

I understand my car isn't the 6ltr or a VE, but i have the same problem in the same rev range as yours, only when under a medium load or half type throttle in 2, 3, 4, 5, 6 gears, when on LPG, if i run it on fuel its all good after a good run. does it feel like its missing or a hesitation and it stumbles along, till it gets out of that rev range and then goes like a rocket? I'm guessing mine is Fuel related, as pcm reset the car runs a dream on LPG and heaps of power too. after about 2 days of driving to work does it play up again. also I have a cold start issue too, with it almost stalling out (on petrol). I run the JTG liquid injection system... just havent gotten around to going back to tuner for a touch up. Guys from work have told me I blow black smoke out the back when i give it boot... so hopefully same for you.
So as Swingtan suggested give the ECM a reset ans see if it helps with the problem.

I think it is strange you felt the need for an aux fuel filter?!?

Anyway, try the ECM reset - and the logging they are talking about isn't just fault codes mate, it is the data about timing advance, knock, air:fuel ratios etc etc etc. get your tuner to do their job - I would also piss off the aux fuel filter to be honest - no need for it!

Thanks guys - how do you do a ECM reset?

The auxilliary fuel filter is off now (for the moment). It was put there as my fuel line has a really harmonic pulse noise that goes thru it that drives me insane at idle. If you lift the bonnet and grab the fuel line it stops. So the solution was some flex fuel line and a fuel filter - works a dream.
Holden were shown the problem and said there was no fix for it.

Tuner has been for 2 drives in the vehicle with me with lappy checking all - he feels it is not a tune issue.
Resetting to factory I suppose will tell the story wont it...??


Also, thanks for the helpful advise guys. Will try a reset if you can tell me how to do it properly...
PS: Just come home from driving and the car is actually worse now I have changed plugs n leads!!

Have your oxygen sensors been checked if there operating correctly, It's possible with all the products that you've put through the tank might of damaged the oxygen sensors leaving this lingering problem after the bad fuel has passed through, The surge could be that the sensors are unable to provide a fast enough signal when it hits closed loop mode.

Just a hunch

I believe one way to do an ECM reset is just disconnect the battery for a period of time. An hour or so? Maybe less? :confused:

I was going to chip in and say AFM until I read that yours is manual.....

Sounds like it will be a process of elimination. Hopefully a short process. My guess is that Holden will flash it back to stock, then diagnose a secondary issue not tune related.

Good luck with it all.

Quote:

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Originally Posted by Fence_sitter

Have your oxygen sensors been checked if there operating correctly, It's possible with all the products that you've put through the tank might of damaged the oxygen sensors leaving this lingering problem after the bad fuel has passed through, The surge could be that the sensors are unable to provide a fast enough signal when it hits closed loop mode.

Just a hunch

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That's a pretty sensible diagnosis - be interesting to hear what the final problem is found to be. I was thinking maybe coilpack/s - but they'd play up across the whole rev range (in hindsight).

Quote:

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Originally Posted by chillicatqld

PS: Just come home from driving and the car is actually worse now I have changed plugs n leads!!

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Why might this be?

Quote:

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Originally Posted by steve_t

Why might this be?

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At this stage it just seemed to be getting... more noticeable in all gears thru the 2000-2500rpm range.

As of today it even is getting more and more crappy to drive. I almost think it may not make it till Monday week to get Holden to look at it without breaking down!
If I am not mistaking even on backoff now it seems to be "missing" also!!!

Cant wait for it to drive properly again....

Quote:

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Originally Posted by Fence_sitter

Have your oxygen sensors been checked if there operating correctly, It's possible with all the products that you've put through the tank might of damaged the oxygen sensors leaving this lingering problem after the bad fuel has passed through, The surge could be that the sensors are unable to provide a fast enough signal when it hits closed loop mode.

Just a hunch

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Pretty sure they havnt been checked... I suggested it - but not sure!!!
Will be spewing if it is just that simple and it wasnt checked... would you see this as being a problem whilst doing a live view on laptop?

WTF DO I DO NOW???

Well after the last 3 days of my car gradually feeling worse to the stage I thought it would even break down. This arvo at 4pm I go out to pick up my lad from kindy. Car is cold and drives as per usual like crap up my hill on way as it warms up.
About 3 klms into my drive something "happens" - I pull off hwy into the kindy road and my car just feels different. Throw lad in car and drive off paying a bit more attention to it. Yep, definately something different... it feels like a new car!!!
The farkin thing after 4 odd months of crap has decided the night before it is getting its tune deleted that it going to "fix" itself!

I have just been for a long drive and all I can say is WOW. I forgot how good this drives and how bad it has been.
I didn't realise exactly how much lag it had trying to get thru the 2-3,000rpm rev range - now it just "jumps" smoothly straight thru it with no stutter/kangarooing at all.
It was pulling like an old 4 cylinder bomb - now it just rockets right thru that rev range. (I am talking just regular driving not hard acceleration as it used to have no problem with "spirited" driving)

WTF could be going on? Will it last?

I have the car booked to go back to stock at 10am tomorrow - and then Holden looking at it on next Monday.
I am scared I cancel both of these and then a week later it all starts again (I am in a hurry as I have till 8th August of Holden warranty left)

What would you do if it was yours? Maybe wait till like Friday and see what happens - hopefully tuner can reflash if something is wrong at that time.

Any thoughts on what may have been my problem and why all of a sudden after 4 odd months all is good again...
Maybe a blocked injector that finally cleared itself?
Maybe a o2 sensor been playing up?

Beats me.... will go for a cold start drive in morning and re-asses my situation.

Any thoughts appreciated.

Maybe your cats were blocked and it finally blew something out of it?

Well just having my morning Arabica ritual and gonna go for a cold start drive... still spun out that after so long a problem that it may have fixed itself.
Will report after this drive and make a decision I suppose from it as to whether it's tune deletion or not.
I suppose even the slightest hiccup I should go down that road just to be safe.

ANY thoughts out there?

I had a Mazda 6 MPS that had it's engine replaced due to a stutter. I was told it was a carbon buildup on the valves. Maybe yours was something similar and it has been cleaned out now?

I use my iPhone and an OBDII cable to keep an eye on not only any codes my car throws, but I can also see the Cat temps as well in realtime. I was able to diagnose a blocked cat due to an increase in temp. Wasn't a lot, but was enough to warrant a warranty claim. No stutter, but a bit of a noise on acceleration that Holden could never find.

The cable is the GoPoint cable and it has paid for it's self already !

Can cars pass Kidney stones?

hahaha... thats what it feels like it needs

I have solved the problem..... thanks to all valid suggestions and helpers.

I will post my results in the next few days. Just sorting out some details!!
But suffice to say - it is good to have my car back!!!!

Quote:

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Originally Posted by chillicatqld

I have solved the problem..... thanks to all valid suggestions and helpers.

I will post my results in the next few days. Just sorting out some details!!
But suffice to say - it is good to have my car back!!!!

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So that Wynns '' No more Stutter '' works then , lol

hahha..... you coul coul could say tha tha that!

Any further update as to the solution???

Any news on this?

Hey guys,
The problem is solved and I WILL be back to post results/problem ASAP.
Just trying to be diplomatic with my approach to my reply....
stay TUNEd

Quote:

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Originally Posted by chillicatqld

stay TUNEd

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Was that a hint? :)

Quote:

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Originally Posted by Wonky

Was that a hint? :)

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One would think so. Interested to see what the issue was. Hopefully something simple.

well my "diplomacy" is getting short lived....
The answer may soon be unravled...

(nothing like a bit of a saga on LS1)!!

OK so without the intention of insulting anyone (ie: tuner) the result of my problem was...
Tuner flashed back in my standard tune and put on standard intake to have it ready to return to Holden to find "the problem" (thinking maybe injectors, o2 sensors etc, water in fuel still, ??)
.... drove away, and all feels like it is back to normal!! yay.

Left it a couple of days to see if nothing bad returns and all I can say it is good to have a car back that doesnt have a "glitch" in it.
It is driving so much better (obviously missing about 30kw) but better in a lot of ways.

Rang tuner to tell them that the car was all better and was told that there was nothing wrong with the tune, my car "just doesn't like running without a MAF"?!
Best to leave it untuned and they would refund my tune cost!!
Now I know NOTHING about tuning cars so I am not going to expand on these comments, just glad to have my car back, and although I was never after a refund (just a fixed car) I am thankful for the offer, and thankful to be driving a car that isnt sending me bonkers....

thanks to all for their suggestions/help.


PS: Does anyone think I should get Holden to patch in an "updated" (if there is one) tune, as it has been 2.5 years since it has been serviced by Holden - maybe there is an updated tune??

Am I interpreting correctly when it seems as if you're saying your tuner used a MAF tune when it was actually mafless??? :confused: If so it sounds like they don't have much idea? :weirdo: