Chubster

Hi Guys,

i brought a 2002 airtrek turbo a few weeks back and have just hooked up a boost guage and taken it out for a test run to see what it is actully making, to my surprise the needle climbed all the way to 18-19 psi, at this pressure and at approximatly 5k revs its sorta farts(like letting the air out of a large ballon) and bleeds off pressure (just a constant pshhhhhhhhhhh), bear in mind this can be heard from the drivers seat at 140km/h.

letting off the accelorator stops the noise and pressing back on the peddle it climbs again then farts and bleeds off the pressure.

im no expert on turbos (my last car was an r33 gts25 skyline) and i dont think this is a good sign, from what i can find on airtreks standard boost is about 0.6bar (9psi)

i am unable to locate the BCS (not under the airbox like i have read)

i have tightend all piping, cable ties on the vacum hoses (clips dont seem to hold them well)

no mods, standerd everthing afaik.

any help would be much apreciated.

(sorry if this is in the wrong section the engine and gearbox is very similar to a evo 7 GTA ad i couldent find an airtrek area)

prockish_03evo

iTrader: (7)

truthfully its hard to tell w/o hearing it myself, but it seems has if you still have a boost leak. i personally had some piping that was bent and would hold boost fine till around 18 than boom my boost guage fluttered around and than settled and actually climbed very slowly so i was like wtf? so after a boost leak test sure enought after about 15 psi i heard a whistle and all it was a pipind the looked like a D vs O. good luck

GregM

iTrader: (1)

Some will run more than 9psi standard, but if its running 18psi, then it must have been played with. It would be interesting to get a wideband on it and get a log to see whats going on.

AndyCT9W

What BOV are you running?

Chubster

Thanks guys, ill look into the above, i dont have a code reader or logger yet.

i may have located the BCS under an intercooler pipe, right hand side, will post a pic when i can, thought i mite swap it out for a MBC on its lowest setting to see if that may be causing the overboosting issue, what is a safe everyday boost level for these TD04 turbos and 4g63t engines?

im going to build a little home made pressure test rig, hook up a compresor, put 20psi into the intake side of the turbo and try and find a leak.

if somone was to have "messed" with it, is it possible for them to have removed the boost limit or change it with somthing like EVOSCAN?

Cheers!!! Heaps of help

Chubster

opps missed that its a Stock bov

AndyCT9W

If someone has messed with the boost via the ecu they would have used ecuflash, very easy to do. Safe boost? An 02 would would do ok up to 20 psi I would imagine (I don't know exactly how different the EVO and airtrek 4g63s are) and the td04 would be ok at that boost but might be out of it's efficiency. BUT (< that's a big bold but) the engine would definitely need a tune to run that level of boost. And I doubt that the stock BOV could take twice the stock boost level. That would be my first check for a leak.

GregM

iTrader: (1)

Yea, bov will probably be leaking. The TD04 can run that boost level, but it needs to be tuned to do so. I'd be dropping the boost back to near the factory level until you get a wideband, cable, ecuflash and evoscan so you can see whats going on.

Check out http://www.airtreker.com/ I've uploaded my xml which is quite detailed. Its not my latest, but at least its correct, as the xml that comes with ecuflash has lots of errors in it, that screwed me up for 6 months figuring it all out.

Where in NZ are you?

Chubster

ok, so if the ecu it letting the boost build that much, will taking out the boost control solinoid and replacing it with a mechanical one drop me back to near standard boost, i assume the wastegate will open itself at a much lower pressure without anything (BCS) interfering?

@GregM, im in new plymouth, how much it that gear going to set me back $3-400 easy im guessing?

GregM

iTrader: (1)

Same here, you've probably seen my Airtrek around.

You could just take the boost control solenoid out and it should run off the wastegate.

It will set you back abit more than that. Talk to Hamish at Evoscan for his software and a cable, hes in Tauranga. www.evoscan.com

I'd recommend a Zeitronix ZT2 wideband and I'd get the boost sensor at the same time so you can log boost. I also have the EGT sensor and a temp sensor for my gearbox. www.zeitronix.com

AndyCT9W

And ecuflash is free software
http://www.tactrix.com/index.php?opt...d=36&Itemid=58

GregM

iTrader: (1)

Just don't use the xml that comes with ecuflash, use mine from the airtreker forums.

Chubster

the evoscan cable i could do but man those sensors are expensive, are there other options?

can the ecu not put out its own boost log to evo scan?

i havent really seen any others driving round lol, and def not with a FMIC, unless you hide it really well.

if i was to flash ur rom would i end up with your tune for injectors fmic turbo etc etc?

sorry about all the questions..... gotta learn somehow..... you wouldent know where to get a service manual would ya?

GregM

iTrader: (1)

Yea, there are, but thats the best. I have mine permanently mounted. You need a wideband before you start tuning - modding.

Its done on the Evo's but Airtrek is abit more difficult. Its easier and cheaper to hook up the Zeitronix boost sensor.

I've had mine for 2 years and the front mount and TD05 were fitted after a few months. Its my daily driver, but its probably not out and about much to be seen.

Yes, you'd end up with my tune, which suits my level of mods. Would make your car run like crap and probably do some serious damage.

When you get a cable and wideband, let me know and I can mod your rom so you can log 2-byte load and raise fuel and boost cuts for you. Once you get that stuff so you can tune, first mod is fuel pump!!

AndyCT9W

I'd still recommend you check your wastegate actuator. I've a handful of overboosting issues caused by wastegates not functioning as they should.