hey people, am new to the scooby world, got me first impreza in feb (an what awsome machines they are!!!!! ), its a 95wrx wagon, an i seem to have a boost prob. it usually boost's at 10psi thru out the rev band till i change gear at about 6k (its a td04 turbo), but lately it wont boost over 0.8? its really annoying, you wanna wind down an have a bit of a play, an the boost drops like a lead balloon.

the only mods i have are, a full decatted system, piper cross panel filter, an HKS dump valve. any advice would be brill. cheers fella's

 

As standard the boost limit is actually 0.8psi on Impreza running a TD05 turbo.

You say the boost drops like a lead ballon when you change gear, Does the turbo spool up quicky once the boost has dropped? If so it sounds like you experencing the joys of normal turbo lag.

However, as you say this problem has only recently occurred, it would suggest a boost leak somewhere. Check all the hoses and clips to make sure nothing has worked its way loose or split.

I remap or chip might be order to sort the boost limitations out and to frank it would be a good idea anyway considering the mods you've already got.

 

are you using super unleaded?

 

Good point, petrol can effect performance a great deal.

Use V-power there are a number of links on here, which have that as the Scooby Nets choice of fuel.

 

10psi is 0.68 bar so it hasn't reached 0.8 bar anyway.

0.8psi is 11.6 bar

 

0.8psi is 11.6 bar[/QUOTE]

no its not!!!!!!!!!

 

yeah am using v-power, its all i use. i cleaned out the boost solonoid with a compressor, all the pipes are ok. (or as far as i can see) i went out just before, boosting at 0.8psi, travling at 60mph, floored it in 3rd, an it shot up to just over 10psi an held there. till the next gear. Whilst its not boosting properly, you feel it all the time trying to kick in, noy too mention the fluttery exaust note at idle

tis driving me mad

 

no its not!!!!!!!!![/QUOTE]

sorry don't know why i wrote that doh 11.6psi is 0.8bar doh

 

Make sure there is no black smoke as sounds like air leak or faulty waste gate actuator

 

alot of people have said, the boost solonoid can fail? am not sure how thats possible but u never know. the other thing is fueling, ie when its getting a thrashing. not enuff juice is gettin thru, so it detects knock? the ignition retards, an it cuts boost OR limp mode as its known?

oh an theres no smoke. only when driven hard between gear changes, you get a little puff of smoke, an thats it. ive got a TD05 to go on, dya think that mit cure it with an sti fuel pump?

does that make sense to any engine guru's at all?

 

limphome mode is 0.5 bar and limited to 4000/4500 revs.
Fuel cut is when your head nearly goes through the windscreen (not nice)
You get 10psi (0.68bar) normally but you mention it won't boost to 0.8bar (11.6psi) or did you mean 0.8psi?
The ecu may need to be altered as the td05 spools up differently,if you want a better fuel pump go for a Walbro (about £85)

 

8psi i ment, sorry. my boost gauge is in psi. its all over the show at the moment? 11psi 9psi 10psi 8psi.

The norm for it is 10psi. when the car cant be arsed. (which is what it feels like when it does it) it lets out a breath, (like its sighing) an VERY!!!! slowly creeps up to 8psi. you can actually hear the turbo (when its running at 8psi) spool on the last bit. when it free's up to 10psi. the difference is unbelieveable!! between it working properly an not at all

 

Ok now i what measurements we using
i guess you may have a leak in a boost pipe somewhere (remove them and have a good look for splits) i know you've had alook but always good to double check imo or dodgy actuator perhaps?

You always speak to Scott t (PolarPerformance) he's had plenty of experience with early imprezas.

 

cool cheers myblackwrx, i will check the pipes at tthe first chance, as for the actuator , av got a tdo5 going on in the next week or so? managed to get me hands on one from scoobyteknix, tis festering in the shed?

i know the ecu is gonna think am taking the pi$$ by puttin a td05 on, but thats unil i can get my mates u8 mines ecu, or a z4. he's CONVINCED the u8 mines will kill my engine! i beg to differ.

thanks for the advice dude!!

 

The u8 is from a 93wrx and will run the td05 (it was designed to) although if it has a Mines chip in it they are mapped aggressively(fuel and boost) and for Jap fuel (100Ron) so perhaps running Vpower+octane booster would be wise.
What mods did your mates car have with the Mines in it as the chip would (most probably) been mapped for specific mods.
The Z4 will work fine (once again designed for the td05)

 

believe it or not, he has a 94 uk wagon. full decatted zorst, pipercross panel filter, hks dv (same mods as mine really) But he has a tdo5 on it already! an the way it drives is how you descibed it AGGRESIVE. boost, on his gauge goes to a maximum of 1.2 at full throttle. i think the z4 would bhe best then... if i can find one. dya think my engine will have a fit by putting a td05 on it???

sorry for all the questions dude, but ive gotta ask.

 

What i meant by aggressive is the map not the driving style .
Has your mate ever had it dynoed as it might have a lot of boost but if the fuelling isn't right the engine most probably go pop and you don't want that.

Just go to the link i've posted as he can chip or remap your ecu (to your requirements) that is in the car already (the J1 resistor gets cut and the chip runs the car any problems reconnect the resistor and the ecu goes back to its original map)

 

The mines ecu that was in my car, now on ebay was boosting @ 1.0 bar not 1.2 bar. I have just got a z4 he he . He is Leying about the v-power seen him puting in bp super and texapoo super ron 97 what can I say but

 

Z4 specs are

WRX (1995/96) ECU Z4 - 12.71psi, dropping to 11.78psi @ 6600rpm. Fuel-cut 15.65psi

Got 1 in my 93wrx and the car is a lot smoother through the gears.

 

i dont think ive ever posted a thread, not ONCE!! were i havnt been slagged off by scalesy.

 

nope he always has a pop at you i have a z4 mines if you are interested chris pm me on here or lads m8 if interested and it runs mint using v power and octaine boost and mine is a my96uk wagon

 

you know I is only jokeing