Turbo_Steve

Help please, peeps.

Have a TD05 on my legacy (it was already fitted with a TD05, this is just a newer one off a WRX) and at the moment the wastegate is connected directly to the compressor barb.

I also have an H&S exhaust, from which I have just removed the splitter mod, thinking this was the cause of the problem.

On WOT, boost quickly reaches 0.7Bar......and then (especially in 3rd & 4th gear) gradually creeps higher and higher. I normally lift off at 1.0Bar because I am still on the standard map, and the knocklink is twitching at this point, though AFRs are still very rich.

I have tried pressureising the wastegate actuator(using a footpump) and it seems to hold pressure, (i.e. isn't leaking) so does ANYONE have any idea what can be causing this? The wastegate armature seems to move freely....any ideas what I can change \ adjust to reduce \ remove the creep?

nom

Erm, from what you're describing, this sounds quite possible & reasonable? As the boost rises, so does the wastegate, but not enough to bleed enough exhaust to keep the boost as low as 0.7bar.
Or have I missed something?

jameswrx

iTrader: (4)

I think it is down to the design of the wastegate on the tdo5. I have been through this a million times in my head as to what could cause. I have tried downpipes, std, hks and open neck with splitter, all gave boost creep.

The only way I've been able to almost keep it under control is run more boost. 1.1bar on scoobyecu map seems to produce a good hold of boost. The lower the boost the greater the creep. It seems to want to run at least 1.1bar.

Pipe to barb as you say about will produce a lot of creep, ie 0.65bar up to 1.2bar, std map on solenoid (with de-cat) will produce 0.85bar creeping to 1.2bar Scoobyecu map (with de-cat) will produce 1.15bar and there abouts all the way.

Essentially wastegate design is flawed, porting of wastegate seems to be the answer if you want control at higher rpms.

Andy.F

Check that the WG can open fully, someone may have adjusted the linkage in the past.
To do this, remove the circlip and lift the linkage off the arm. Adjust the threaded rod so that the actuator arm needs pulled out just 1-2mm to fit over the pin. This will ensure maximum available wastegate travel without losing spool up.
If you have the early (fixed) type, you can bend the bracket to have the same effect.

Andy

jameswrx

iTrader: (4)

tried that, I even wired the wastegate fully open, still crept.

Turbo_Steve

Thanks Andy, will try that. As the car previously had a TD05 on it, and the only differences are a new TD05 and the H&S exhaust, I assumed it was the exhaust at first, but I guess it is concieveable that the actuator has been adjusted. I had a feeling it was worth trying something like that.

Jameswrx, have you tried the standard downpipe? Did that still creep? Is it the original turbo or is it possible it's running a different compressor?

rayman_2

hi if you are interested, i have a very good doc on the subject based the wrx subaru boost creep. it basically shows how to elimate it completely with some nice pics.

email if interested.

Turbo_Steve

Update:

Well....I've tried everything I can think of now.

ECU control is crap....fuel cut all over the place, but it DOES seem to be able to keep the whole thing stable at 1.0Bar (once it's cut out twice on the way up! D'OH!) but it manages to stop the creep past 1Bar.

Here's the weird part. Connect the actuator direct to the compressor housing and the boost holds steady at 0.7Bar until about 5500rpms.....in 3rd or 4th gear....when it starts to slowly creep and creep until BAM fuel cut.

I have tried two actuators, check all the hoses for leaks, adjusted the first actuator all over the place, checked for blockages in the compressor nipple.......
and STILL I am getting boost creep.

I chopped the splitter out of my downpipe...made no difference.

I am pretty much at my wits end. I am about to buy a Dawes to see if this will hold the boost steady at 0.9-1.0Bar, but as the actuator alone seems to not be able to hold 0.7Bar, I doubt it.

Why can the ECU hold 1.0Bar and yet nothing else can?
And why am I getting the creep in the first place?

This is really getting to me now

Turbo_Steve

Sorry, just re-read above.....can understand WHY is creeping....

but am confused as to why ECU can hold it steady at 1.0Bar? Just having enough pressure to hold wastegate open? Sorry to seem a little dumb, here....

POC

Hi mate, i've been having an identical problem on my MY95 WRX type RA, was doing my head in. The boost would hit 10psi then climb to the 16pis peak, car felt sluggish etc.

Solved it this evening by following some good advice from Tweenierob, fitted a dawes. It now hits the boost, each and every time in evry gear and holds it, the car is a weapon, pulls like a steam train!!

Get a dawes mate, problem solved.

Cheers

Paul

Turbo_Steve

Right. Dawes it is until I get the new software.

Cheers

jameswrx

iTrader: (4)

Did have a Dawes..

I'm pretty sure I still got boost creep with that too.

More boost is the answer, the lower the target the greater the boost creep in my experience.

bdolgu

Same here, cant get the boost on my standard'ish MY96 below 1bar at anything above ~5.5k on 4th and 5th.

Have a dawes, but that does nothing to help.
Porting the wastegate would help...

And something like a scoobyecu (with higher boost targets and fuel-cut) "fix" it as well.

/Ola

nom

Well, it depends...
If your wastegate is fully open & the boost is still rising, porting might be a good move, or it might be a restriction because of the downpipe - where is the dumped gas going? Enough restriction there & no matter how open the wastegate is, it's not going to help.

jameswrx

iTrader: (4)

Downpipe is not the issue in my case.

Turbo_Steve

Downpipe is open neck...exhaust is 3"....so not a problem, unless there is severe turbulence.

Turbo_Steve

Dawes now fitted, and set at 0.9Bar. Things seem more stable.....except in 4th, which is still suffering from creep at 5500rpms and above.

nom

Next thing I'd want to know, then, is what your wastegate duty cycle was before the Dawes (and just to check that you followed Andy's advice?). It sounds to me as though the actuator is as far out as it can go (so 100% duty cycle) which is still not dumping enough exhaust, hence creep... but the question is - is the wastegate fully open at this point? If it is, the only thing I can think of is having the wastegate ported.

Turbo_Steve

How would I measure Boost Solenoid Duty Cycle? Select Monitor?
(I don't have access to one)

Your point about adjusting the actuator arm is good: after having no joy with the original actuator I removed it and fitted one from my old TD05 (which seemed to work just fine) which I haven't adjusted yet.

However, I found adjusting the old one by even the slightest amount caused the turbo to spool SOOOOOO slowly as the wastegate wasn't closing properly.
As I know this actuator worked just fine on the old TD05, I didn't bother to adjust it.


As I have a pair of TD05's now, neither of which actually work on the car, am considering trading both in for a nice hybrid with a WARRANTY.

nom

That might be a good idea
Yup, DeltaDash, etc. is the way to read wastegate solenoid duty cycle! Don't think there is another way... (well, select monitor maybe?).
The furthest out the actuator should be set is so that at rest, the arm is just pulling the wastegate shut (it can lengthen a little when hot, apparently...) but yes, this may well slow boost build right down - I have no idea how the standard ECU works or copes with this sort of thing!

ktomass

A bit confused here; you get 0,7bar when direct connection from turbo niple to waste gate. We get 0,5 with the same setup and as far as I read posts here think many others do too.

If your wastegate arm was adjusted then it doesn't fully open.

Hope this helps (MY92 with VF12).

K.

Turbo_Steve

Actuator to bleed nipple hits 0.7Bar straight off the bat (which is what I believe a TD05 is supposed to do) but then proceeds to gradually increase and increase and increase past that point.
Adjusting the actuator arm opened the wastegate, causing boost to build VERY slowly....but still crept in 4th gear.

At this point I posted on here, and was told that the TD05 just won't hold 0.7Bar, as the wastegate just won't flow enough.

So I went and got a dawes and set it to 0.9Bar, which is the state I am in now. With the Dawes set to 0.9Bar, boost creeps slightly in 3rd and a little more in 4th, but seems a lot more stable.

The ECU has always had problems: Even on the original turbo with no mods the ECU would surge to 1.1Bar on cold days. But if I put the ECU in control of my new turbo, it flips straight up to fuel cut, but then settles at 1Bar of boost all the way up the range with no creep. How the ECU can do this when the dawes can't, I'm not sure, unless it is sucking the actuator into closed position using the vent line on the 3port solenoid.

As you can imagine I am very frustrated by all this: I want to get on and tune the car, and currently I can't even get it to run standard.

As mentioned, I understand some of the companies who provide Hybrids will do a discount on a trade in of your old TD05. So it might be worth me trading BOTH my old turbos in: I've tried ringing Lateral Performance, but no one ever answers. Will keep trying.

Have no money left this month, and MoT is rapidly approaching (and there is other stuff that needs fixing too!), so coughing up for a Hybrid is NOT my favourite option.

As I have injectors, defi guages and a mapped chip and god knows what else all sat in a box waiting to get fitted once I get this sorted, (defi's need a controller, and I just need a fuel pump and regulator to have a complete set of mods) you can imagine my frustration!

But I am aware the chip raises the fuel cut to 1.7Bar or more, and the last thing I want is the turbo to creep up this high!!!