New engine - related issues?

[Atik]

Just wondering if there was anything that could point to stuttering when on WOT. I had a replacement engine a couple of weeks ago, and on normal road use, the engine feels fine and drives super smooth. But when on track last weekend, with hard WOT I was getting intermittent stuttering.

It didnt feel like a coilpack issue as that was much more pronounced. This particular stuttering felt almost like minor fuel starvation or blockage of the injectors or something. It was very faint and would just momentarily pull power away and then go back on and off and on. If I had about 80% throttle, the acceleration was smooth but obviously not running properly. Couldnt be fuel starvation either as I had more than half a tank (100 miles travelled prior to track and I normally can get about 280 between fills).

Could the injectors be clogged? Or maybe spark blowout? Detonation? Must admit that when it was happening out on track I wasnt listening for knock so cant be certain what it was. I have tried a 3rd gear WOT while on a 'private road' with the EBC switched off and although I didnt get to redline the gear, I felt no stuttering on that occasion.

Must also point out that the new engine doesnt like my old boost settings. I used to get about 10psi boost on low boost and about 13.5psi on high boost. The new engine seems to get around 7psi on low boost and ALWAYS get fuel cut when on high boost setting. Also noticed that the idle boost pressure is much higher than before. I used to get around -10psi on idle but now its steady at -2.3psi.

Anyone shed any light on any of these problems? Could any of these be related to other issues or is there anything I should be on the lookout for?

[foxdie]

Just to add to this thread, I'll be EvoScanning Atik's car on Thursday night whilst he tries to reproduce the issue, one thing I'll be watching for is things like knock etc, will post up the CSV once it's logged, but does anyone have any advise on what we should be looking for?

[Nutter_John]

Atik I will point you to the post I made before you fitted the engine , you are running a custom remap from your old engine on this new one . I advised that you to run a stock map until you could get it checked out on a dyno . You have no monitoring of Knock nor AFR's yet you are running foot to floor tests

Now I would say have a look at the spark plugs as it sounds like you are getting blow out

[Wodjno]

Just wondering if there was anything that could point to stuttering when on WOT. I had a replacement engine a couple of weeks ago, and on normal road use, the engine feels fine and drives super smooth. But when on track last weekend, with hard WOT I was getting intermittent stuttering.

It didn't feel like a coilpack issue as that was much more pronounced. This particular stuttering felt almost like minor fuel starvation or blockage of the injectors or something. It was very faint and would just momentarily pull power away and then go back on and off and on. If I had about 80% throttle, the acceleration was smooth but obviously not running properly. Couldnt be fuel starvation either as I had more than half a tank (100 miles travelled prior to track and I normally can get about 280 between fills).

Could the injectors be clogged? Or maybe spark blowout? Detonation? Must admit that when it was happening out on track I wasn't listening for knock so cant be certain what it was. I have tried a 3rd gear WOT while on a 'private road' with the EBC switched off and although I didnt get to redline the gear, I felt no stuttering on that occasion.

Must also point out that the new engine doesnt like my old boost settings. I used to get about 10psi boost on low boost and about 13.5psi on high boost. The new engine seems to get around 7psi on low boost and ALWAYS get fuel cut when on high boost setting. Also noticed that the idle boost pressure is much higher than before. I used to get around -10psi on idle but now its steady at -2.3psi.

Anyone shed any light on any of these problems? Could any of these be related to other issues or is there anything I should be on the lookout for?

Don't know whether you have been following my hesitation issues Atik ? Had them all the time i had this car.. But only above 5800rpm at WOT ? Is that the same as ur's. And is more apparent with higher Boost.

Mine doesn't hesitate anymore :dance:

Not since myself and Paul changed the Cambelt :book:

We found that the Back Cam was 1 tooth out /help So was opening 2 1/2 degrees before it should.. New Belt on and all lined up and the car is now super v6 smooth and revs to the redline with ease :D

Not saying yours is deffo this issue.. But i had changed all other things that could have contributed to hesitation.. I was very excited to see that it was 1 tooth out in anticipation that it might be the end to my hesitation issues /yes
And it was :dance: :dance: :dance: :dance: :dance: :dance: :dance: :dance: :dance: :dance: :dance: :dance:

Hope it's a much easier fix than mine Atik.. But it's quite easy to check this 1st /yes

Cheers

Wodj

[AlanDITD]

Your getting -2.3psi whats that in inmg

Thanks to Foxdies amazing google maths....thast 118 inMG which is well out of spec...

Its probs either a leak or a compression issue, or anything else that effects vacum

[Wodjno]

Your getting -2.3psi whats that in inmg


Ah.. Just seen this bit /Hmmm That is low Atik /yes

Wonder if my Vacuum has changed since the Belt change ? I'll take a look an let you know..

[foxdie]

For the masses, -2.3 PSI == -118 MMHG == -4.68 INHG

[miller]

I remember you mention this Atik, was it on WOT when cornering or could you get it in a straight line?

[AlanDITD]

Ah.. Just seen this bit /Hmmm That is low Atik /yes

Wonder if my Vacuum has changed since the Belt change ? I'll take a look an let you know..

dont you mean high :PSee my post above!

[Atik]

John, I know :( I was hoping that just the remap and low boost would be safe as it wouldn't be putting max demand onto the engine components. Apart from the track session I havent been driving hard at all and have every intention of getting to Eurospec to get the remap and boost tweaked.

Wodj, I had a cambelt shange at the same time as the engine change. Not sure if Nick would make such a schoolboy error :p but its worth noting and I will check this out at some point.

Alan, noted and will look into getting it checked. Will try the stock BOV on the car just incase it could be that.

Mike, it was on straight line acceleration that I was feeling the hesitation. Dont think I was ever on WOT in the corners :p

But after two straights of hesitation, I backed off the car and took the session at around 70-80% throttle and never felt it after that.

[Wodjno]

dont you mean high :PSee my post above!

No i mean Low /yes As in Low numbers /yes

[Mark 4]

I have a similar issue to Atik.
Only got the car on the road last Friday so still some logging to do but I have had to turn my boost controller down quite a lot. I also have hesitation (started at Japfest) only on WOT, so will be investigating this week.

[AlanDITD]

No i mean Low /yes As in Low numbers /yes

but its minus 2.3 so its higher than normal /yes

[Nutter_John]

try as Glennn says check the cambelt alignment , but also double check the spark plugs

[Wodjno]

but its minus 2.3 so its higher than normal /yes

Well mine idles at -9.4 psi !! So i stand by what i said.. That Atiks is Low.. /catfight

[mike74]

i would say its almost definitely a boost leak somewhere, given that the idle vacumm isn't what it was before & its boosting lower too. maybe a split boost hose or a clamp not done up tight enough? did you replace all the necessary gaskets with new ones when swapping the engine over? worth checking all pipes, hoses clamps & even breather pipes to make sure they're ok before going too deep into things. chances are it'll be something cheap n easy to fix (hopefully). i had a very similar sounding problem with an audi s2 i used to have. i checked & re-checked everything i could pipework-wise (no change), fiddled with the actuator in case of a problem there (no change) & replaced the dump valve (no change). turned out there was a pin hole in the intercooler that only really showed itself under hard acceleration...
any time since then ive had an issue with stuttering its been a leak somewhere or, occasionally the plugs! hope you sort it mate

[Atik]

Will feel up the pipework this evening (oo-err) to check the easy stuff, but until I get EvoScan hooked up to log knock etc I will be driving like a granny!

[Nutter_John]

Will feel up the granny!

Now thats just wrong Atik :p

[Atik]

PSML! /lol

[Nick Mann]

Low vacuum and lower than normal boost with fuel cut at low boost says a loose pipe to me. Probably a control pipe of some sort.

I'd suggest a good look at the boost control pipes, especially the red silicon jobbies to the boost controller. You'll need to remove the snorkel and the flexi from the intercooler to the plastic elbow for that.

The Cams were locked for the cambelt change - if anything is a tooth out, it can only be the crank. I can't believe that 1.) I would have missed the crank being a tooth out and 2.) the car would still run with any kind of power at all if that were the case.

If you have a slight leak in the pipework somewhere, then you will not get boost as before, your vacuum will be lower than before, you will get fuel cut at lower pressures.

[Nick Mann]

Actually, if you have a small boost leak, you will be over fuelling at WOT, which could also be causing the stuttering.

[Atik]

Low vacuum and lower than normal boost with fuel cut at low boost says a loose pipe to me. Probably a control pipe of some sort.

I'd suggest a good look at the boost control pipes, especially the red silicon jobbies to the boost controller. You'll need to remove the snorkel and the flexi from the intercooler to the plastic elbow for that.

The Cams were locked for the cambelt change - if anything is a tooth out, it can only be the crank. I can't believe that 1.) I would have missed the crank being a tooth out and 2.) the car would still run with any kind of power at all if that were the case.

If you have a slight leak in the pipework somewhere, then you will not get boost as before, your vacuum will be lower than before, you will get fuel cut at lower pressures.
Thats the kinda direct info I like :) Thanks Nick. I can handle that kind of checking tonight so will keep you all posted.

At least my radiator is working fine now /Banana

[mike74]

do you know anyone that could do a smoke test on the inlet to locate leaks? im not sure if a couple of lungfuls of B&H's finest would cut it or not...

[Atik]

I'm assuming a smoke test is simply setting a smoke grenade type deal off under the car and looking for any flow thats not normal? Could a smoke pellet work for that? Set a couple off under the car and look for leaks?

[AlanDITD]

what i love about this forum is the way good advice is ignored until
"someone special" posts....crazy!

[Nick Mann]

You put the smoke pellet in the turbo pipework and seal it in.

My local man ordered the equipment a few weeks ago, I can check if he has got it yet if you'd like?

I have a home-made apparatus that allows you to pump air in to the pipework, but it is difficult to pump enough by hand to hear any kind of hiss. I have found a leak using this method and soapy water though.

Feel free to pop round here (with or without Jason) if you want to have a look using my home made stuff.

[Atik]

what i love about this forum is the way good advice is ignored until
"someone special" posts....crazy!
Sorry Alan, are you suggesting I'm ignoring good advice?

[foxdie]

Feel free to pop round here if you want to have a look at my home made stuff.

Dirty bugger! :laugh:

[Atik]

You put the smoke pellet in the turbo pipework and seal it in.

My local man ordered the equipment a few weeks ago, I can check if he has got it yet if you'd like?

I have a home-made apparatus that allows you to pump air in to the pipework, but it is difficult to pump enough by hand to hear any kind of hiss. I have found a leak using this method and soapy water though.

Feel free to pop round here (with or without Jason) if you want to have a look using my home made stuff.
Cheers Nick, guess we could swing by to get it checked out on Thursday :)

[Nick Mann]

Cheers Nick, guess we could swing by to get it checked out on Thursday :)

Just give me a shout before heading over, to check I'm in!

[AlanDITD]

Sorry Alan, are you suggesting I'm ignoring good advice?


It does look that way sometimes mate, but then it happens all the time on the forum. But you can delete these comments as they have no relevance to the thread. Im just making an observation.

[Nick Mann]

Alan - looking back, your comment on a leak was a small one in with other stuff. Also, Atik is only paying more attention to me because I was the one with mucky hands in his engine bay. Lots of people suggested boost leak before me - I mentioned it to underline the idea, not to take away from others who had already said it. I also felt I could point out some of the hoses I didn't like when I worked on the car.

And - if it was me you called "Special" - thanks! Not many people have called me that before! :P :D

[Nutter_John]

he meant special needs Nick :p

[Nick Mann]

he meant special needs Nick :p

I thought that was more likely! :(

[Atik]

Alan, I got no problem with the comments staying in the thread, but can you point me to other instances where you feel I've ignored advice posted up? PM me them if you want, as I feel that your comment is unwarranted. I have ALWAYS searched for any problem/solutions before I post and where possible I approach other knowledgable forum users via telephone/PMs/pagers/chat/in person to get advice and help.

The reasoning to putting up this thread was that I had a number of seemingly unrelated small issues that could all be interlinked to indicated an overall larger fault. I'm sorry but I have had a lot of time and effort and money put into this car and had major components fail on me for no apparent reason, so if you feel I'm asking questions that have been covered before, feel free to either ignore my questions or point me to the topics of discussion where it has been dicussed previously.

[AlanDITD]

I didnt mean special needs at all...i meant it in a genuine way that you do know the cars very well.

[Nick Mann]

I didnt mean special needs at all...i meant it in a genuine way that you do know the cars very well.

:D :sweethear /Banana


@ Nutter: => /Nuuu :smug:

[AlanDITD]

Atik,

I wasnt reffering it just at you, it just happens alot. I dont have instances to hand as it pisses me off for about ten minutes and then i usually forget about it.
Its also nothing to do with searching and covering previous topics.

Its a simple manners issue as far as im concerened! Advice from other members isnt neccacarily ignored, but often it isnt acknowledged either.

Then the knowledge of the "special ones" come along and its praise for that information...

In this instance no one picked up on low idle pressure, i came ot the chat worked out some things with you, and we talked about a possible solution, and then a post went up on the forum..its then ignored, not even a thanks in the chat iirc.

Like I said this looks like im having a pop at you, which well i am but its a more general issue that happens on here all the time and this time coupled with not smoking really pissed me off.

Most likely me over reacting of course.

[Nutter_John]

Go and have a fag you moaning git :p

[foxdie]

Go and have a fag you moaning git :p

I told you, I don't offer those kind of services anymore :p

[swinks]

Atik, I had the same issue last year going to Thoresby Hall. I've posted on a forum even due to these symptoms. Apparently it was loose vacuum hose going from wastegate to ebc selenoid. Hope yours is the same :-)

[Atik]

Alan, you advised me it might be a compression and/or vacuum issue in the chat. I acknowledged that in there. I posted up the thread as there were additional issues that I needed to clarify. I wasnt ignoring your advice. See post number 10 where I clearly acknowledged your input.

I understand you might feel that I'd given Nick's pretty much identical reply more weight, but his advice included checking the red silicone pipe which is individual to my car and the fact that he pointed it it out after having worked on it it two weeks previously, was very valuable. I'm sorry if it came across as ignoring your advice, it was not intended. But it just wound me up suggesting that I was ignoring advice when I clearly wasnt.

Wodj's advice regarding the tooth being out is totally valid, but as Nick has said, he doesnt think that he would have missed that when doing the cambelt. That puts Wodj's suggestion to the back burner. I havent ignored it, but as its the least likely option (in this particular case), I will probably check that if other checks do not show any issues.

[Mark 4]

Actually, if you have a small boost leak, you will be over fuelling at WOT, which could also be causing the stuttering.

My AFR's are high 10/low 11's. That's not rich enough to cause stuttering - is it ?

[Wodjno]

My AFR's are high 10/low 11's. That's not rich enough to cause stuttering - is it ?
No.. There fine..

[Nick Mann]

No.. There fine..

/yes

[Turbo_Steve]

Alan, I agree, I've seen you offer good advice only for it to be passed over a number of times.

I suspect the biggest problem is that you tend to fire an answer into a thread without neccesarily explaining your thinking. This can be thought provking, and inevitably someone experienced will come along and agree - my first thought reading this "knock" and then reading your post thought "ahh yes, that'd do it".


I'd also add that you have been known to make facecious posts that don't add anything to a thread. Whilst sometimes funny, it doesn't always do a lot for your credibility, dude.

But mainly, I think the problem can be summed up with:

It ain't what you say, it's the way that you say it,
It ain't what you say, it's the way that you say it,
It ain't what you say, it's the way that you say it,
That's what get results



:D You'll feel better when you're off the Smokes, dude.

I may post up something motivational shortly....

[John TheAntique]

With all the scares about volcanic ash destroying aircraft engines I hesitate to suggest this but I've used fine talcum powder instead of smoke as it shows up beaut on the pipe where there is a split. On second thoughts ignore this.

[bradc]

Does indeed sound like a boost leak. With evoscan you will be able to log airflow through the MAF (obviously) and if that is particularly high for a lower power output that expected then obviously that would point to a boost leak.

Shouldn't be that hard to find though :)

[Atik]

I'm gonna ignore Brad's suggestion :p /STP

[lancerevo3]

I'm gonna ignore Brad's suggestion :p /STP
/lol /lol /lol /lol

[bradc]

Meh I don't give a sh1t anyway ;) I just give help whereever I can and if people don't listen to me I'm not the type to get upset and whinge about it, I'll just find other people to help in other threads.

[Wodjno]

Meh I don't give a sh1t anyway ;) I just give help whereever I can and if people don't listen to me I'm not the type to get upset and whinge about it, I'll just find other people to help in other threads.

Good for You :thumbsup:

[Atik]

Dammit. He didn't bite :D

I didnt get around to checking the car last night as it got a little busy at home. Gonna leave it for tomorrow now while I have the expertise of Jason and maybe Nick to help me out with some EvoScan.

[Atik]

Its probs either a leak or a compression issue, or anything else that effects vacum
What does he know?!? Load of tosh as usual :vulcan:



.



.



Cheers Alan. You were spot on. I have replaced two of the boost pipes and now can happily used high boost setting. Got 13.6psi on a few power runs this evening (while logging with EvoScan to monitor knock). Believe it or not, the red silicone pipe I had on was too short and was being pulled too tight and was kinking where it connected to the nipples (oo-err), and one boost pipe was either off altogether or partially off as it came up as I moved it to get a better view.

Running stupid boost again and it feels good to be planted to the seat in any gear :D

I will still be taking it easy until I have had the car dyno'd and checked out thoroughly, and boost and map tweaked.

Thanks you everyone for the advice and help. CVR4 triumphs once again /Banana

[aboo]

Glad you got it sorted Atik.

[Subaru ETA]

Meh I don't give a sh1t anyway ;) I just give help whereever I can and if people don't listen to me I'm not the type to get upset and whinge about it, I'll just find other people to help in other threads.

unless that person is vr4-fan, then you give him ****! :p :evil2:

[stuey]

Moving on from Atiks boost leak issues, I think I had the same, as at Japfest I had the weird spiralling boost, gauges and boost controller reading vacuum but no control over boost settings so fuel cut all the time.

I checked the small hoses and did indeed find one with a split, one loose and one not connected at all.. where does this one go.. ?

I checked Nicks description of the route but can't really make head or tail of where some of the pipes go..

Loose hose seem to be around the plastic intake elbow area, and comes from a Y splitter that goes down into the engine V at one end and the other connects to the plenum just behind the throttle


Other pipes I've got are:
One from the dash (from the boost gauge and ProfecII I assume) that splits and into the plenum and a little round metal thing (looks bit like a fuel filter, but I know it's not)

Another from the Top of the plenum that goes down into the depths of the engine V.

Another from one side of the Boost controller valve that goes down into the engine V.

Another the Boost control valve that goes to the plastic intake pipe.

There are some others but can't see them being wrong as they don't look touched for a while..

Any ideas for my missing pipe ?

[Nick Mann]

It's really difficult to follow all that!

I don't suppose the pipe not connected is just off at one end? Or is it off at both ends?

[stuey]

I know.. !! I'm having trouble working out where they go.. seems to be connected to low somewhere, and nothings been changed on the car so assume it's supposed to go somewhere.. Too many bleedin' pipes and hoses on this thing.. I'd take some pics but that probably won't help

[stuey]

Right, using my logic, as this stray pipe already is attached to the plenum so already had a vacuum present I just blocked it off with a screw.... and hey presto ! no spiralling boost, power is back, and no fuel cut.

Haven't had a chance to try the other settings on the boost controller but seems to have solved it. Just a bit worried where it was supposed to be in case something that's supposed to have a control hose/pipe now hasn't got one..

[Turbo_Steve]

Chances are it will be a fuel system purge or emissions control line : it still needs looking at, but it's unlikely to be dangerous and at least the car is back to normal :)

Best thing to do is get someone close to you like Nutter John to have a look and sort it : reckon an hour of his time, Max.

[Nick Mann]

If it comes off the plenum by the throttle body, towards the front of the car, then it should go to the fpr solenoid.

[The Vee]

Hope this helps