Re: Eureka!

Glad you got it sorted
where abouts is the actuator? I may have to check over my pipes when i get the chance.
Did you replace the whole pipe or just cut the bad bit off?

Re: Eureka!

minimad99 said:

where abouts is the actuator? I may have to check over my pipes when i get the chance.
Did you replace the whole pipe or just cut the bad bit off?

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If you follow the tube from the VGT valve (overboost) that goes towards the front of the engine then you'll soon find it. I think this is only an issue for anyone who's had their overboost valve moved up by the battery. The original fiat tubing that goes to the old location under the headlamp is most likely a lot more reliable

Didn't see exactly what was done to the tubing but just glad it's fixed.

I could kick myself for not changing ALL the tubing 2 years ago when I first had a problem :bang: The thing is, two type of tubing had been used and I assumed the 2nd type was OK which turned out to be quite a mistake :doh:

Result Argo.

When i relocated my VGT valve I noticed that some of the original piping was quite stiff almost plastic like on the bends. I assume this is reinforce it.
I reused the original pipework but may check it over when i get round to cleaning the EGR valve. I did look at replacing it before but you have to make sure you get a strong pipe due to the vacuum created.

bozzy said:

Result Argo.

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Thanks Bozz - over the moon about it basically as this is the fault I've been trying to track for what must be 2 years now. It started as poorish consumption but over the last year I've started to notice the lag too and over the last month it's been obvious something is wrong. In actual fact I got the same garage to check out the car about a year ago, for poor consumption, but that time they totally failed to find anything wrong (only cost me 1 hour labour though)

I'll tell you another thing too. I'm real glad I had a AT generic map installed instead of a live map - as otherwise I'd be in right mess now. Now everything is properly matched it feels like a completely different car :woot:

The VGT turbos are rare to failure, glad you found the problem If anyone wants to know more about variable geometry turbos, theres some good info here: http://www.holset.co.uk/mainsite/files/2_5_1_5-VGT.php
(I work for Cummins/Holset )

Glad you got it fixed.
Has the fuel economy improved much, or are you now driving too enthusiastically to tell?

john55 said:

Has the fuel economy improved much, or are you now driving too enthusiastically to tell?

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I guess I'm sticking my neck out a bit but with all the extra low end torque (huge difference in that area) it's difficult to imagine it wont be improved but I'll report fully once I've had time to check.

I've also got a perfectly good VGT valve and MAF sensor spare now. Could be worse I suppose - at least I didn't buy a new EGR valve

BigFoot032 said:

Congratulations, Argonought!
I have had the same case, with a little difference in the position of the demage. It's close to anti-poluttion system. Look the picture and watch the pipes! Better then turbos or VGT actuators... ​

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I think I recognize that - isn't it the vacuum reservoir (feeds the VGT & stop valves)?

They checked all that on mine too.

I've just been thinking, that on mine you couldn't dream up a worse fault if you tried. I think I was wrong about the turbo and that it's default condition is really NO boost. Once the VGT valve operates then I think it gradually lowers the pressure to the actuator which in turn causes the turbo to generate more boost.

Because of the leak I think there was hardly any movement of the actuator but all the time the ECU would see low pressure at the MAP sensor and request the VGT valve to generate more boost. This would eventually cause some movement of the actuator but also due to the nature of the break in the tubing (check the photo) then the tube would temporary and suddenly seal itself.

From the drivers perspective, this would seem like an explosion of power at the top end (even more extreme when remapped). Also, the break would tend to stay sealed so if going through the gears quickly then power delivery would appear sustained. However, once back to low speed town driving then the break would tend to open up again. I really believe this has been going on for years and getting just very very slightly worse all the time.

On thing's for certain. If anyone has similar symptoms then go out and buy a tube and connect it between the VGT valve and the actuator (even if only on a temporary basis). If there was a leak before then you should feel the difference instantly. If it doesn't improve then simply reinstate the original tubing.

Argonought said:

I think I recognize that - isn't it the vacuum reservoir (feeds the VGT & stop valves)?

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Yes, that's it exactly.

Argonought said:

From the drivers perspective, this would seem like an explosion of power at the top end (even more extreme when remapped).

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I have Red Dot Racing remap and I'v got the explosion of power at about 2800-3200 rpm. At the lower rpm I could not see any movement of the actuator rod and I was prepare myself for turbo cleaning (and possible unbalancing ) or just a VGT actuator repair / replace. But, we trace the problem from the actuator pipe, up to overboost sensor (replaced on batter case) and till to vacuum reservoir. At the vacuum reservoir we'v got the vaccum pressure, and the valve is working. Then we suspects on overboost valve and remove the pipe from it, but there no vaccum, too. At the end we'v start to trace the pipes and found the demage.

Now, in this perspective I think that was the problem due to some misstake with the fuel filter replacing and accidenlty change the pipe routing.

Now, my Stilo was alive, again! And I have the real boost. I'v made some tests and accelerate in 5th gear from 80 km/h to 120 km/h in just 8.4 s! Before remapping this was 10.7 s, and with the hole in the pipe it was 25+ s.

Re: Eureka!

Argonought said:

Therefore, amazingly, in 3 years: Total faults = 3 glow-plugs + 1 brake light bulb :spin:

... and a final big thanks to Italian Car Spares (01202-660678) for a great piece of diagnosis

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Congratulations, and well done to Italian Car Spares!

BigFoot032 said:

Now, in this perspective I think that was the problem due to some misstake with the fuel filter replacing and accidenlty change the pipe routing.

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Yes; I don't think it's common to have problems there as my pipework was still in good condition on the reservoir side

Now, my Stilo was alive, again! And I have the real boost. I'v made some tests and accelerate in 5th gear from 80 km/h to 120 km/h in just 8.4 s! Before remapping this was 10.7 s, and with the hole in the pipe it was 25+ s.

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Certainly makes a massive difference doesn't it I've now got torque I'd forgotten all about (you tend to not notice when you lose it very gradually over a 2 year period)

Have you timed yours in 4th (64kmh - 129kmh)? :slayer:

I have measured about 10 s (9.5 - 10.5) in 4th (64kmh - 129kmh), just like you are. The boost is really incredible now!

BigFoot032 said:

I have measured about 10 s (9.5 - 10.5) in 4th (64kmh - 129kmh), just like you are. The boost is really incredible now!

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What engine power do you have (without/with mapping)? 115 bhp or 140?

Slavomir

No such thing, but 155 BHP

BigFoot032 said:

No such thing, but 155 BHP

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from 115 or 140?

BigFoot032 said:

No such thing, but 155 BHP

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Did you read my post? I have remapped Stilo and 155 BHP now. Ok?

BigFoot032 said:

Did you read my post? I have remapped Stilo and 155 BHP now. Ok?

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slavomir was only asking what your car came out the factory as

I'm sure like mine it was 115bhp - but it was just a question

Ok, sorry...
It's was 115 BHP without remap and 155 BHP after remap. It would be clear now...