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Surging/pulsing TTID problems

32K views 99 replies 6 participants last post by  kez 
#1 ·
Today, one of my TTid's is surging in 3rd gear.

from 2000rpm all the way through to 5000rpm, the boost drops and then climbs (pulses).
from 2000-3000 ish it drops to 3/4 and the back up to full, once a second ish, from 3000 it drops to 1/2 and back up to full, and from about 3750 it just stays at half.

it did it 3 or 4 times on the trot, and then would do a couple of accels at full boost, before going back to the above pulsing.

No errors showing on Vaux-Com.

It was serviced last week, has a partial EGR blank (10mm hole) and a Maptun stg1 tune.

Any ideas?
 
#3 · (Edited)
EGR, never cleaned, egr pipe and egr was looking clear when I fitted the partial blank 12 months ago.

Inlet manifold was full of oily soot though

DPF last regen was 240m ago, 58% full now, not currently regenning

2008 car with 79,000m

Luckily I have two TTid's (3 with fathers), so maybe I'll swap some bit over with the wifes.
 
#4 ·
if it hasnt been done in 12 months i would get it cleaned asap and the pipe that feeds it just as a matter of course they need cleaning once or twice a year...

look on kez "cars poorly" thread from a few days ago he took some pics of it with a how 2 on the way

you said "one of my ttid" meaning you have 2 ???

at least you could try swapping over some ancillary components if the egr clean doesnt sort it

i would also suggest doing a regen drive mid revs motor way 20-30 mins should clear it out

also look at the swirl flap bar and see if its attached ,

not to scare you but the early ttid had issues with the flaps being swallowed if it wasnt updated later one
 
#8 ·
replace "o" ring and get that egr and pipe cleaned if it was like that a year ago, also do throttle body and MAP ;)

i clean mine about twice a year, the last 6months only done local miles hence i needed to clean 2months earlier

if the car is mainly driven local commutes the emmissions system will clog up and then lead to other issues
 
#10 ·
As others have said EGR clean, maybe try replacing the MAP sensor as well (or swapping one over). Definitely try a manual DPF as well. You can prove if it's the MAP sensor as well by unplugging it and going for a spin - you'll get an EML but wont get limp mode. And where have you been hiding with your 8000 posts !?!
 
#11 ·
Not getting limp mode or eml currently, regens happen every 400 miles ish. No DPF back pressure being measured as such, about 1.5 psi.

Will try some logging and and have a clean down and parts swap.


As to 8000 posts... I was a mod and then 1 of the 3 admins on here when it was first sold off. :cool:

Children and wife mean I have little time now.
 
#16 ·
hi,not been on for awhile,cars been fine,done the clean and replace just before my trip to france and 1000miles later and an average of 45mpg with afully loaded wagon i have to say its the best saab i have had.I keep an eye on oil levels as after my software upgrade my aero can go into a regen as soon as temp touches middle,sadly just as i am in traffic.One question,my sportwagon ttid is on a 58 plate,how can i tell if it has the so called" upgraded swirl flaps"
 
#17 ·
Its the 08-09 that were the problems after that I believe they revised them.....

Kez will know for sure....

Tbh I'm suprised I havnt sold my deflapped on.... My tid ones fly out one ebay can't get the scrap ones fast enough to recon them and its more of an issue on the early ttid than the tid ever was
 
#18 ·
MY 2010 have them, maybe some late MY2009, i very much doubt that yours will, even if a car was registered in 2010 theres still a chance that it wont have the upgrade because the car/engine could be from 12/18months earlier if you get what i mean
 
#19 ·
I was going to look into my problem further on Monday, but things have beaten me to it....

Feels like my TTid is running on only the larger turbo....

This morning on the only accel point to work, out of 30mph and up a hill in 4th is started bucking badly with boost torque gauge bouncing up and down. Changed up and thought that odd.

Tonight noticed when accelerating round a large roundabout in 2nd that there was no pickup, then whoosh.

Checking now, and at 1500rpm boost torque gauge goes to. Half, at 1750rpm it goes to three quarters, at 2000rpm you get full boost and it's off.

Possible idea of error so far

Seized smaller. Turbo
Jammed open boost diverter
Waste gate controler failed

Tech 2 I got doesn't work, so opcom later.

No error codes at all, EGR pretty much blanked, no black smoke.
 
#21 ·
The big vacuum pot is holding vacuum and the turbo switch over lever is free and smooth.

I can suck it up myself with a short length of hose.

I don't know which was is which though, is vacuum (up) big turbo and no vacuum (down) little?

Checked again and no smoke and has good boost over 2000rpm. No error codes of any sort.

Boost controler check in Vaux-com is a pass. (raises revs to 1400 and does things with vacuum) which can be heard too.

EGR is mostly blanked and doesn't appear to be an issue.

dpf is 50%, regenned 245km ago, no back pressure under boost.

looking more and more likely the little turbo either isn't going round (siezed or foreign object - swirl flap?), or the big turbo boost charge diverter spring plunger thing is jammed open.
 
#25 ·
OK, it looks like the controllers are working ok.

if you start the car, the High pressure wastegate (big vacuum divertor) shuts, just like it does on the wifes car.

looking at 2 vauxcom boost req/actual plat from mine and her cars, my boost req's (and thus actuals) are much lower.

rpm abs boost req wifes v mine
1250 150 v 150
1300 160 v 160
1350 176 v 171
1400 192 v 176
1450 200 v 184
1500 216 v 200
1550 240 v 200
1600 256 v 208
1650 264 v 215
1700 270 v 224
1750 280 v 224
1800 284 v 232
1850 290 v 236
1900 296 v 240
1950 312 v 256
2000 320 v 256
2050 320 v 264
2100 320 v 272
2150 320 v 280
2200 320 v 304
2250 320 v 320
 
#27 · (Edited)
No, normal, it's just completely lethargic below 2000rpm

Slight vibration at 1200rpm, possible early dmf failure.

disconnected battery for 15 mins tonight (usual have you tried a reboot....)

I'm suprised by the low boost requests though, if little turbo is down, I'd expect request to be normal, just not delivered.

here's hoping it's just the low pressure larger turbo bypass stuck open...
 
#28 ·
been out tonight after children went to be.

large vacuum divertor un plugged and hose plugged:
large turbo only, no boost until 3000rpm and then rocket ship

large vacuum divertor with full vacuum and then temp silicone hose plugged. original hose also plugger
small turbo only, same as before, limited boost until 2000rpm, then full boost from 2250rpm.

So it looks like little turbo is working/doing something, but the car is not requesting for full boost/torque, of the little turbo is not doing what it should as well as it should.

does anyone know if there is a failsafe map? I have tried disconnecting the battery for 15 mins already though.

maybe try reflashing the std or stg 1 maps again.
 
#29 · (Edited)
Garage thinks the spring in the boost pipework may have broken (valve is forced open when the larger turbo gets up to boost).

Spring is pretty much where the [1] points too, unfortunately the [1] is the whole exhaust/turbo setup. I can't find a parts listy for bits in there......

Could be an expensive way to get a spring
 

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