TD04 High Boost Issue

wtdash · Post by **wtdash** » Tue Feb 03, 2009 5:09 pm

I want to get the Revtronix Stage 2 chip.

I'm running the newer/lighter spring TD04 Wastegate Actuator and still getting 10+ psi @ the WG (should be <8 psi).

From what I've read here and elsewhere the '02-05 TD04 WG should be about 10 psi ON A WRX, and the the '06+ should be <8 psi ON A WRX. I emphasize the WRX since I have limited/no psi info w/the TD04 on an EJ22T....but rumor is that our larger displacement vs the WRX 2.0 would cause a higher boost???

I have 2 of the lighter spring WG actuators and I get same result w/both, so there's something in my setup that's causing an unusually high boost.

I've also tested this with 2 of the stock boost control solenoids (BCS) and got the same result....since my WG is higher than the BCS, it just bypasses it @ anything over 8.7 psi anyway.

The car starts/runs great, other than a high (1800+RPM) idle until warm. When I had the MBC installed @ 14psi w/the FCD installed it pulled hard and smooth all the way to redline.

My Setup:
- '93 EJ22T swapped into a '90 Legacy.
- TD04 w/newer/lighter spring WG actuator
- '06 TMIC
- 480cc injectors (just installed - made no difference) (EDIT: Orig. listed as 440cc)
- Coffe cup/reasonator delete mod
- Snorkus mod
- Diamond coil pack
- Turbo 4EAT tranny and Turbo TCU
- 3" Turbo-back exhaust
- Bellmouth downpipe
- STi fuel pump
- Lightweight (not UD) pulley

Thoughts/suggestions?

Post by **Legacy777** » Tue Feb 03, 2009 7:12 pm

Have you tested the wastegate actuators with a hand held pump to see what pressure they start to open at?

If not, you should do that.

Also, how are you reading the boost pressure? You may want to use Vikash's scan tool, if you have a laptop to compare what the ECU is seeing vs. what you may be seeing on a gauge.

I ran my TD05 with the stock boost control setup, and it puts me generally around 9-10 psi.

Personally, if you're seeing around 10psi, I wouldn't worry too much about it.

wtdash · Post by **wtdash** » Tue Feb 03, 2009 7:38 pm

Josh,
I need to test w/the pump...you recommended that earlier, and I'll try it tonite.

I also need to put the cable together and try the scan tool.

The 10 psi creeps to 12-13 @ WOT in 3rd/4th (4EAT)....and I hit fuel cut.

That's why I've been trusting my gauge as the fuel cut @ 13psi matches what I've read online.

Thanks

Post by **Legacy777** » Tue Feb 03, 2009 7:47 pm

The hight boost in 3rd & 4th is boost creep. It is the nature of the turbo and the down pipe you are using.

Without a gear based dependent or better closed loop boost control setup, you probably will not be able to correct this.

Do the checks, but I will guess that you find everything to be normal.

RJ93SS · Post by **RJ93SS** » Tue Feb 03, 2009 7:48 pm

try the pump, my td04 was around 9-10 (out of an 04). do you have "matt's vacuum bypass". it sound like something to do with the way all your vacuum lines are hooked up after the swap. check here http://web.archive.org/web/200510281912 ... vacuum.png

wtdash · Post by **wtdash** » Tue Feb 03, 2009 8:05 pm

I don't have the vac bypass.

I did do a lot of vac hose work after installing the TD04, TMIC and and CC mod, so that could be an issue - not denying that.

I'll make my own diagram of how it's hooked up and let the experts provide feedback.

But since the car ran well w/out spikes, etc. and the boost gauge's readings were consistent w/what I've read I should expect, I thought I was golden.

Thanks

RJ93SS · Post by **RJ93SS** » Tue Feb 03, 2009 10:14 pm

yeah hopefully it works out. i just went to see mike a couple days ago and i'm waiting on your tune to be done so i can do my tune. i got stage 1 1/2 right now and it feels WAY better, i cant wait for stage two. let me know if i can help

RJ93SS · Post by **RJ93SS** » Tue Feb 03, 2009 10:16 pm

if you need to try any different parts, i am about 15 minutes away from where mike lives, so solenoid's ect are available if you need them.

wtdash · Post by **wtdash** » Tue Feb 03, 2009 10:29 pm

RJ93SS wrote:if you need to try any different parts, i am about 15 minutes away from where mike lives, so solenoid's ect are available if you need them.

Awesome...thanks for the offer!

skid542 · Post by **skid542** » Wed Feb 04, 2009 4:09 am

If you need a hand this week, I can make myself available after work. I usually get back into town around 5:30-6:00 these days.

I'd like to offer a reason of why it's not working but I'm a bit stumped. But do let me know if you need a hand, I'd be happy to help.

wtdash · Post by **wtdash** » Wed Feb 04, 2009 4:53 pm

skid542 wrote:If you need a hand this week, I can make myself available after work. I usually get back into town around 5:30-6:00 these days.

I'd like to offer a reason of why it's not working but I'm a bit stumped. But do let me know if you need a hand, I'd be happy to help.

Lee,
Thanks...it's appreciated...but I'm not sure what to do either.
Td

wtdash · Post by **wtdash** » Wed Feb 04, 2009 5:08 pm

Legacy777 wrote:Have you tested the wastegate actuators with a hand held pump to see what pressure they start to open at?

Tested both WG actuators and they started to open about 7 and fully open @ 10 psi.

Not sure where the extra couple of psi is coming from as it'll climb to 12-13 psi if I stay on the throttle.
- Bellmough downpipe ?
- EJ22 vs. EJ20 ?

I've reached the Peter Principle in my engine knowledge.

Post by **Legacy777** » Thu Feb 05, 2009 7:25 pm

wtdash wrote:Tested both WG actuators and they started to open about 7 and fully open @ 10 psi.

Not sure where the extra couple of psi is coming from as it'll climb to 12-13 psi if I stay on the throttle.
- Bellmough downpipe ?
- EJ22 vs. EJ20 ?

I've reached the Peter Principle in my engine knowledge.

If you've tested the WG actuators and verified the boost pressure going to the actuator is correct, then your problems are as I mentioned earlier a function of your setup, primarily the turbo and down pipe.

I don't recall if you mentioned you did this, but have you tried running a line directly off the turbo compressor nipple to the WG actuator? What happens when you do this?

I really don't believe you're going to be able to do anything to correct this without altering the turbo, or changing to a different downpipe.

wtdash · Post by **wtdash** » Thu Feb 05, 2009 8:01 pm

Josh,
You're on the same page as post # 6 HERE.

He suggests porting the wastegate.

I've ran 3 scenarios w/my vac lines:
1. Stock - w/BCS
2. Direct from WG actuator to turbo
3. MBC - using the intake as the boost source.

# 1 and #2 allowed boost creep to 12-13 psi; # 3 would hold steady @ 11 psi.

I don't understand why there's a difference w/the MBC, though.

So, getting the turbo/wastegate ported and/or put the stock downpipe back on are the fixes.

Thanks again for the input/feedback.

RJ93SS · Post by **RJ93SS** » Thu Feb 05, 2009 8:29 pm

it must just be the elevation, it would make perfect sense. i'm at sealeavel with the same setup, and i was seeing 9-10 sometimes 11.

ScottyS · Post by **ScottyS** » Thu Feb 05, 2009 8:52 pm

Just for the heck of it last night, I tested this on my car with an 02 WRX TD-04.

Went straight from the turbo outlet nipple to the WG actuator. I measured 6psi using a boost gauge teed from the #1 intake runner.

I live at 5000MSL.

Post by **Legacy777** » Fri Feb 06, 2009 6:42 pm

That is odd about the MBC holding at 11, while plumbing directly from the compressor outlet to the wastegate actuator gives you 12-13.

The only difference between those two setups would be that you stick a MBC in between that hose. I'm assuming this is how you setup you MBC?

Personally....I wouldn't spend any money porting the wastegate of a TD04

legacycentral bbs

A forum for 89-94 BC-BF(BJ) Legacy Owners and Fans

TD04 High Boost Issue

TD04 High Boost Issue