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Tallpointy
Monday 10th January 2005, 20:58
Hello every one.

My 850T5 has just developed a problem and I am at a bit of a loss as to how to fix it.

The symptoms are the car now accelerates like a 2.3L low compression 850 Volvo to an amusing swaney whistle type noise.
The noise rises in pitch in time with the turbo and not the revs or roadspeed. It's not the turbo spooling as I can hear the normal very quite high pitched whine as it does so.
I found a couple of the vacume hoses had come off but their refitting made no difference to the lack of performance.
The standard boost guage shows the boost going to the start of the white section,as it used to (the car is bog standard) but the acceleration that went with it has gone.

I can't find any leaks (it doen't make the noise on idle thus making it tricky for me to fault find).

Of course it wouldn't do this in the month of checking out that the car was OK, but as soon as I order some new performance plugs, leads, and a K&N filter.

Sorry about the essay!
Any help would be gratefully received.

Cheers,

Darryn

Justin
Monday 10th January 2005, 23:43
It may well be running in limp home mode, even if there are no lights on the dash.

Get the ecu read for fault codes, especially if vac lines were off ;)

Tallpointy
Tuesday 11th January 2005, 21:11
Ta!
I have seen the codes listed in the Haynes comic and shall set about checking them out.
I didn't bother as there were no lights up.
Ho hum.

If any one out there needs to know how to read the codes give me a yell.

I'll let you know the results as soon as I get the chance to have a look.... It's always bleedin' dark by the time I finish my enforced cycle home from work as I haven't dared to drive the five.

Cheers for your comment Justin.

Take it easy all.

Justin
Tuesday 11th January 2005, 21:25
No worries mate, just hope you get her back on her feet ;)

Tallpointy
Thursday 13th January 2005, 21:55
Hi,

I've got the codes that were on the ECU:

3-2-5 ECU memory loss
5-3-5 Turbo regulator valve fault

I cleared the codes.

Checked all the vacuum hoses I could find, and took her for a spin.

Still the comedy noise, boost on the guage but not much acceleration.

Stopped, checked the ECU and no fault was reported.


By reseting the fault log would the car recover from limp home mode or is there more for me to do??

Any ideas or sugestions would be gratefully recieved.

Cheers!

Bracer
Friday 14th January 2005, 09:24
Even thou T-5's are notorious for turbo whistle I'm guessing before you had this power loss it wasn’t' that pronounce !

I would suspect a split hose somewhere especially when you say a couple of vac pipe popped off.

Your boost gauge should reach between half way to 3/4 into the white area as this is the "On Boost" area. If your only getting to the start of it your not producing any boost or more to the point your loosing it out a hole somewhere.

Check ALL the vac lines and replace if they look worn or perished. Another common area to look at is the hoses going to the Intercooler both top and bottom pipe can split and cause many scratching head moments.

Lets me know how it goes over the weekend !

Regards

Steve :wink:

Tallpointy
Tuesday 25th January 2005, 20:21
Changed every vac hose I could.
Noticed a pipe missing tho... Can I confirm that the pipe that should be fitted just after the MAF sensor (on the plastic elbow) should go to the middle of three connectors on the turbo control valve?

I'm getting pretty desparate now and may have to take the car in to a garage :0(

Cheers for yer help.

Justin
Tuesday 25th January 2005, 20:29
Hi mate, the pipe on the elbow should go to the BCS, middle pipe.

Sounds like you have a split turbo hose though to be honest. The only way to check is remover ebery turbo hose and inspect it, the noise would be air escaping through the split.

Notorious causes are the inlet hose that has a T piece on it going to the idle valve, always split on the join and is impossible to see without removing. The other famous one is the bottom hose made of rubber that goes to the intercooler, it chafes on the lower bulk head and wears through.

Keep us posted mate ;)

Tallpointy
Saturday 5th February 2005, 16:41
I have found the problem, when grubbing round with the pipes I decided to have a look in the turbo .....

Oh dear. There would appear to be a shortage of impeller fins on the inlet side. Looks like they have been ground off. (kind of goes with the way how the performance dropped off)


Are reconditioned ones OK?
Can anyone recomend a supplier?
Is there a cheap performance upgrade available through this misfortune?

Oe even better does anyone have a second hand one (94-95 T5 (15G Conical outlet)) I can trade beer tokens for?

Bracer
Monday 7th February 2005, 09:46
I have found the problem, when grubbing round with the pipes I decided to have a look in the turbo .....

Oh dear. There would appear to be a shortage of impeller fins on the inlet side. Looks like they have been ground off. (kind of goes with the way how the performance dropped off)


Are reconditioned ones OK?
Can anyone recomend a supplier?
Is there a cheap performance upgrade available through this misfortune?

Oe even better does anyone have a second hand one (94-95 T5 (15G Conical outlet)) I can trade beer tokens for?

You can have mine if you contribute to the 19T for Steve fund :wink:

glock19
Tuesday 15th February 2005, 16:31
Somehow, I knew it was the impeller, but why 15G ? I thought it was TD04H-13G, no ?

Just a point I want to debate with my friends, the T5 is consider a soft turbo whereas the T5-R is a full blown, right ?

Wobbly Dave
Tuesday 15th February 2005, 17:25
Depending on transmission - 15G for Auto, 16T for manual the major difference in power between a T5 and T5-R is the map on the ECU. Turbo's are the same for both specs

Tallpointy
Thursday 17th February 2005, 19:51
Cheers Bracer,

E-mail me to let me know what size 19T contribution is needed.

I'm going on the listings on this site (my car is a 94 T5) to work out the turbo type.
Other than dismantling the car is there a way for me to confirm the type?

As my car is standard will I need to add 8mm to the wastegate arm?

You sir are a gentleman, a schollar and an acrobat.

Justin
Thursday 17th February 2005, 20:44
10mm for the waste gate mate :)

Bracer
Friday 18th February 2005, 09:32
I will have a count up this weekend to see how close I am to the 19T.

Thanks

Steve

:wink:

Tallpointy
Saturday 19th February 2005, 19:28
Cheers,

The WG arm lengh question came about 'cos in your spec.s I see 'W/G Rod -8mm' and am not sure what it means or even if it's for this turbo.

Ta,
Darryn

Bracer
Monday 21st February 2005, 10:48
Cheers,

The WG arm lengh question came about 'cos in your spec.s I see 'W/G Rod -8mm' and am not sure what it means or even if it's for this turbo.

Ta,
Darryn

Yeah it would need to be reset and it is part of the turbo. I've adjusted the pre-tension of the WG actuator to give earth shattering spoolup :eek:

But I dont advise anyone else to try this without a full set-up as you could bend a rod :cry:

Steve :wink: