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Intermittent Boost Problem

Posted:
Sat Dec 05, 2009 8:01 am
by 04GTLIB
Guys.
I noticed a little problem with the wagon the other day whilst out and about.
I'd just made a quick stop to grab a couple of things at the shop, started the Lib and headed off home when I noticed it wasn't getting full boost.
I immediately thought boost leak but there were no apparent noises/squeals/air leaks at all.
The car drove fine, it just wouldn't get any more than 7-8 pounds boost.
I continued to drive on and off boost to see if I could hear anything or try and source a problem, stopped at a set of lights and when they changed I checked again and low and behold I had full boost again.
Now this being the first turbo car I've owned, I'm a little vague as to all the bits that make these things do what they do, but could this be the actuator playing up or maybe the boost solenoid?
Any help/suggestions guys would be very much appreciated.
Cheers,
Rusty.
Re: Intermittent Boost Problem

Posted:
Sat Dec 05, 2009 8:06 am
by Arith
I'd check the actuator. I'm starting to see quite a few fail and needing replacement because they aren't strong enough to hold boost anymore. Otherwise the other issue is that you have a wagon. Have you thought about trading up to a sedan?

Re: Intermittent Boost Problem

Posted:
Sat Dec 05, 2009 8:20 am
by 04GTLIB
Arith wrote:I'd check the actuator. I'm starting to see quite a few fail and needing replacement because they aren't strong enough to hold boost anymore. Otherwise the other issue is that you have a wagon. Have you thought about trading up to a sedan?

Sedan....
My god Jim, that word is disgusting and I wouldn't be caught dead in one.
Now getting back the the other not so important part of your response...
Would the actuator cause intermittent problems Jim?
I found it a little weird that it was ok for a while, it then played up and a few minutes later it was ok again.
I have access to another actuator, but I wanted to get a few opinions before I started playing around with it so to speak.
Cheers,
Rusty.
Re: Intermittent Boost Problem

Posted:
Sat Dec 05, 2009 9:27 am
by Arith
Hmm, probably need someone else to verify intermittency. I've known of a few people who have lost boost due to the actuator, but didn't check on whether the boost loss was constant or intermittent. Norm (libsti)? You out there buddy?
Re: Intermittent Boost Problem

Posted:
Sat Dec 05, 2009 9:36 am
by senator
Rusty a you using a boost controller? did you checks all your plumbing around the tmic, and boost gauge plumbing…????
I experienced a very similar issue to what you described, it turned out to be the avo tmic, the threaded holes which held the bov in placed were stripped. I started noticing the car was not pulling as strong when on boost, until one day I heard the bolt shooting out and bouncing around the engine bay…. Long story short…. Phat gt worked his magic by fitting stainless helicals and problem solved
Re: Intermittent Boost Problem

Posted:
Sat Dec 05, 2009 10:37 am
by 04GTLIB
senator wrote:Rusty a you using a boost controller? did you checks all your plumbing around the tmic, and boost gauge plumbing…????
I experienced a very similar issue to what you described, it turned out to be the avo tmic, the threaded holes which held the bov in placed were stripped. I started noticing the car was not pulling as strong when on boost, until one day I heard the bolt shooting out and bouncing around the engine bay…. Long story short…. Phat gt worked his magic by fitting stainless helicals and problem solved
Not using a boost controller Tony, it's been flashed tuned.
I've had a good look around all lines and pipework and haven't been able to see any issues/problems.
It just seems strange that one minute it was showing 17 pounds boost (on the boost gauge) and performing normal and then it was only showing 7 pounds.
It wasn't making any air loss or air leak noises, it just drove like it was only getting half the amount of boost it normally gets.
Re: Intermittent Boost Problem

Posted:
Mon Jan 04, 2010 9:54 am
by west_minist
If everything is mechanically good, its the car disabling the boost. Try a better fuel or get her retuned
Re: Intermittent Boost Problem

Posted:
Mon Jan 04, 2010 10:06 am
by west_minist
Take from here:-
viewtopic.php?f=17&t=7206&p=108750#p108756
The car uses some call the IAM to switch fuel maps and disable/enable boost and other functions. If you look closely, the car is running 10psi or so of boost, which is wastegate boost.
Sometimes these legacies fuel requirements are pretty high and need retuning for local gas.
Re: Intermittent Boost Problem

Posted:
Mon Jan 04, 2010 10:11 am
by Hotwire
I was wondering that if Ignition Advance Multiplier (IAM) has dropped so low that Wastegate duty has hit 0%
You say your car has been flash tuned - who did the tune, and in what weather?
Just wondering if you're in hot weather now you're getting heat soak in the IC and its causing detonation, thus the IAM dropping. I noticed in my factory car, in winter (<20deg ambient) tune is fine, but anything over 25, IAM sits around .825 and in summer (32+ lately) tune is shit and IAM is sitting at .525 ....
Re: Intermittent Boost Problem

Posted:
Mon Jan 04, 2010 10:26 am
by tangcla
I have nothing useful to add to this topic.
I just came into admire Russell's avatar.
Re: Intermittent Boost Problem

Posted:
Mon Jan 04, 2010 10:33 am
by west_minist
I find it surprising that aussie tunes are so unstable. hummmmmm.
I tuned cars from 0-C to 39+C. The tune if possible show include the environmental conditions as much as possible. Call the customer back in when these changes occur for a retune.
Re: Intermittent Boost Problem

Posted:
Mon Jan 04, 2010 10:41 am
by tangcla
west_minist wrote:I find it surprising that aussie tunes are so unstable. hummmmmm.
It's not a generalisation to be made for all tuners. But yes there are a number of so-called tuners around who know nothing about cars or the way engines work; that goes for any country, just that we seem to have less decent tuners

Re: Intermittent Boost Problem

Posted:
Mon Jan 04, 2010 10:45 am
by Hotwire
tangcla wrote:west_minist wrote:I find it surprising that aussie tunes are so unstable. hummmmmm.
It's not a generalisation to be made for all tuners. But yes there are a number of so-called tuners around who know nothing about cars or the way engines work; that goes for any country, just that we seem to have less decent tuners

Actually, its the stock tune that I was referring to (and Parso_Rex agrees) that they seem to have taken the JDM 100Ron tune, made some minor and useless changes and stock the ADM cars run poorly in warmer weather!
Remaps, well that's another story all together and much debate can be found on here

Re: Intermittent Boost Problem

Posted:
Mon Jan 04, 2010 10:47 am
by tangcla
Hotwire wrote:Actually, its the stock tune that I was referring to (and Parso_Rex agrees) that they seem to have taken the JDM 100Ron tune, made some minor and useless changes and stock the ADM cars run poorly in warmer weather!
Ahh right. Yeah the stock tune is kinda crummy. On our gen4 they ran it extra rich because of the problems Australia has had with the gen3 B4 (tuned for 100RON and not detuned for Australia)
Re: Intermittent Boost Problem

Posted:
Mon Jan 04, 2010 5:16 pm
by 04GTLIB
tangcla wrote:I have nothing useful to add to this topic.
I just came into admire Russell's avatar.
Glad you like the new one Clarence.
Guys.
I wanted to let you know there was a small leak near the TMIC. Paul pointed it out to me when I had the tune tweaked the other week.
Thanks to all for your help, comments and feedback.
Cheers,
Rusty.