csa Posted July 25, 2008 Share Posted July 25, 2008 The car has started to behave odd. Boost is set to 1.2 bar, but when giving it stick, it sometimes boosts 1.6 and a minutte after it's back to 1.2 when floring it again. any ideas? Quote Link to comment Share on other sites More sharing options...
michel lane Posted July 25, 2008 Share Posted July 25, 2008 looks like boost spike , whats do you have controlling the boost ? if its a standalone controller , check the solinode , mayneed cleaning . Quote Link to comment Share on other sites More sharing options...
csa Posted July 25, 2008 Author Share Posted July 25, 2008 it's controlled by the AEM EMS Quote Link to comment Share on other sites More sharing options...
csa Posted July 25, 2008 Author Share Posted July 25, 2008 just been out for a spin. When it's boosting 1.6 it's clear to hear that the wastegate is letting gas out of the srreamer pipe and now closing correctly...whats happening? Quote Link to comment Share on other sites More sharing options...
michel lane Posted July 25, 2008 Share Posted July 25, 2008 sounds like a split in the pipe worrk to the waste gate , check this first. Quote Link to comment Share on other sites More sharing options...
jevansio Posted July 25, 2008 Share Posted July 25, 2008 Wastegate jamming? Split diaphragm in Wastegate? Quote Link to comment Share on other sites More sharing options...
csa Posted July 28, 2008 Author Share Posted July 28, 2008 i've just tried to clean the solenoid. now it giving a quite loud buzzing sound. seems to be wasted. could I switch to a manual adjustable boostcontroller to see if that eleminates the problem, or would the aem be "confused " about that when it's set to control boost? Quote Link to comment Share on other sites More sharing options...
jevansio Posted July 28, 2008 Share Posted July 28, 2008 Take the boost control out of the equation totally, just run a boost pressure feed from where-ever you currently take it, to the side of the wastegate, leave the top nipple of the wastegate unused. This will run the car with the boost pressure set by the wastegate spring, 0.8 BAR is most common I have seen. This will prove your wastegate is working in it's most basic setup (or not). Quote Link to comment Share on other sites More sharing options...
csa Posted July 28, 2008 Author Share Posted July 28, 2008 okay, and the aem wont go abesh*** when I do that? Quote Link to comment Share on other sites More sharing options...
jevansio Posted July 28, 2008 Share Posted July 28, 2008 okay, and the aem wont go abesh*** when I do that? No, the spring rate is below your normal boost setting, the spring shouldn't (if the wastegate is operating correctly) boost over that. The AEM may well be controlling the solenoid, but as far as it is concerned boost will never reach the level the AEM is trying to achieve, it will just think boost is building up slowly. The 1st time you go for a run, do it gradually (in a high gear on a motorway or similar), if everything is working correctly the wastegate will open. if there is a problem with the wastegate it may well keep on boosting, be carefull you keep an eye on the boost, if it goes over what you normally boost to you have a problem in your wastegate/boost feed line. Quote Link to comment Share on other sites More sharing options...
csa Posted July 28, 2008 Author Share Posted July 28, 2008 thanks! will try this tomorrow Quote Link to comment Share on other sites More sharing options...
csa Posted July 30, 2008 Author Share Posted July 30, 2008 just tried this. boost is stable now (at 0.7 bar) but I still think the car pulls uneven from pull to pull, and it still gives that whesteling sound sometimes... Quote Link to comment Share on other sites More sharing options...
jevansio Posted July 30, 2008 Share Posted July 30, 2008 With the uneven pulls you are experiencing, can you log what boost you're seeing on the AEM to confirm this, it maybe in your head Quote Link to comment Share on other sites More sharing options...
csa Posted August 4, 2008 Author Share Posted August 4, 2008 Unfortunately I can't log this my self (or well, have to learn how to do) but there’s definitely something wrong somewhere. When boost is coming on in a high gear, you can hear a pretty loud whistling sound starting before max boost, so it can’t be the wastegate opening. Just a thought: when I assembled the current turbo, I had problems with screws holding the compressor housing. 2 of the had “eaten” the aluminium and couldn’t be tightened that good. Don’t get me wrong, they are tight, but not THAT tight. Further there’s large O ring in that turbo (Precision T67) so could it be the turbo blowing out air from the sides? Or would a problem like that be 100% consistent? Quote Link to comment Share on other sites More sharing options...
suprattgaz Posted August 4, 2008 Share Posted August 4, 2008 This sounds like my problem. But my pressure drops a bit, with a weird whistling sound. Watching this with interest Quote Link to comment Share on other sites More sharing options...
csa Posted August 8, 2008 Author Share Posted August 8, 2008 okay...changed to wastegate...it wasn't it :-( Quote Link to comment Share on other sites More sharing options...
JamieP Posted August 8, 2008 Share Posted August 8, 2008 If it was me i would pressurize the system to find any air leaks before i do anything else, my money is on the turbo leaking, ive had the same problem you are describing before on that car and it was the turbo. There is a thread around here somewhere about it. Quote Link to comment Share on other sites More sharing options...
csa Posted August 8, 2008 Author Share Posted August 8, 2008 okay...the turbo not beeing assebled "tight" enough? Quote Link to comment Share on other sites More sharing options...
csa Posted August 8, 2008 Author Share Posted August 8, 2008 btw it's not the wastegate sounding wiered...I've just changed that as well (4 hours hard work for nothing, but had to give it a go...) Quote Link to comment Share on other sites More sharing options...
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