The saga of the underperforming LCR... part 14

[RobM]

As some know, I've been having a problem with my LCR pretty much since day one of owning it. The problem is a lack of power at times, when it simply wont perform.

Well, I've changed the DV, N75 etc and the problem still happens. I have to say, when it's driving well it's bloody superb! But at random moments it just doesn't work.

For a while now I've been wondering if this problem is heat related. It often happens after the car has sat idling for a few minutes, or if I've been crawling along in slow moving traffic. For instance, Saturday the car was stunning to drive! Went out and about in it all morning and it was better than ever (had just changed N75 to a J variant and it's superb!).... but later on, I had to sit in a car park for 5 mins waiting for the Mrs', the car was idling, and when it came to driving home from there I had nothing, no performance at all.

Well, today something happened that hasn't happened before. As per usual, driving in slow moving traffic caused the car to stop performing once the road opened up. Put your foot down, nothing. Normally this is the way it stays for the rest for the journey, but today, the power came back! Yup, just got onto the motorway, put foot down, nothing. Changed into 5th and put foot down again and the car started to pick up! From then on it was lovely again. That's never happened before.

What the heck could be causing this? My guess is a temp sensor of some sort, but what could it be that would kill the power and then later allow it to come back again?

Any expert opinions would be very gratefully received at the moment!

Cheers

Rob

 

[virdi]

Air Charge Temperature?

You need to get a Diagnostic done

 

[RobM]

I've ran VAG-COM on it numerous times and the only consistent message I'm getting is relating to a boost leak (17705 I think, can't quite remember). Nothing else shows up.

 

[RikH]

do you have any silicon hoses
a TIP or anything rob?
id be checking hoses for loss of performance, but if it comes and goes thats really strange, defo need a vag-com test if you havent already and see what it says if anything

 

[RobM]

All standard hoses, none have been changed that I'm aware of. The fact it comes and goes it what really confuses me. If a pipe had split I'd expect to see the problem all the time. But like I said, sometimes it's perfect to drive! All morning Sat it was fantastic, it was fast, responsive and performed like an LCR should! But after being sat for 5 mins, if that, it killed it.

 

[virdi]

could be a dodgy vacuum pipe - Which is stopping the engine / turbo building up boost....

...aren't these classic systems of the standard dump vavle?

 

[RobM]

could be a dodgy vacuum pipe - Which is stopping the engine / turbo building up boost....

...aren't these classic systems of the standard dump vavle?

All classic symptoms, which is why I have changed my DV to a Forge 007P. And if it were the pipe, would it not cause these problems consistently, all the time? And why would it suddenly bring back the power when driving?

 

[virdi]

good point.

Have you checked your spark plugs? - But if it were the plugs - the car would most likely mis fire...

But I have heard cases of boost blowing out the spark - If the spark plugs are not gapped correctly...

 

[richybigman]

I had a similar problem with the car not performing 100% all the time, turned out that the TIP wasn't on the turbo properly. Original hose was split half way round where someone had tightened up the jubilee too much.

 

[RobM]

I had a similar problem with the car not performing 100% all the time, turned out that the TIP wasn't on the turbo properly. Original hose was split half way round where someone had tightened up the jubilee too much.

Did yours run perfectly some times though? Or was it always under performing?

Interestingly, I've read a few comments to say that a sign of the TIP failing is an extra loud air movement noise coming from the passenger side footwell, which is something I have had recently. Sound right?

 

[bentaw]

perhaps it is something to do with southampton cos i have running issues too my idle is not stable it fluctuates not a lot but isnt steady at all, sometimes when driving slowly in second gear especially in the wet for some reason as i approach the 2000rpm mark my car seems to hit a wall or flat spot. There are days where i go to boot it and nothing like it is in limp mode and other days it is like a bullet train it just pulls and pulls.

 

[richybigman]

Did yours run perfectly some times though? Or was it always under performing?

Interestingly, I've read a few comments to say that a sign of the TIP failing is an extra loud air movement noise coming from the passenger side footwell, which is something I have had recently. Sound right?

It was totally intermittant, sometimes it would pull like a train and other times like a tram! And now for some reason i'm only hitting 20psi instead of 22psi

 

[warren_cox]

When I had similar issues I ended up having to take mine to a rolling road centre so it could be tested under load. Dealers seem tostruggle to resolve these kind of issues that relate to pipe leaks as they don't leave a clear and indicative fault code.

Take all your hoses off, one at a time, and check for any cuts or breaks around the jubilee clips, or also in areas where the pipes may come into contact with other engine parts.

Also, although I know you have a new DV, do the leak test on it (eg. remove it from the car), use a ballpoint pen to push up the internal plunger to its limit inside the DV, then whilst it is held there stick your finger over the top vacuum hose output of the DV. If the plunger stays locked up inside the top of the DV then its fine, if you hear it spring back to the bottom of the DV you have a leak.

I had a brand new DV, but then changed the spring to a yellow spring. Somehow I caught the rubber washer in the top cap when screwing the DV back together and then I couldn't work out why the car couldn't hold boost. If I hadn't had a boost gauge I'd never have known where to look for the issue.

Check all the pipes as the std ones are rubbish.

 

[bentaw]

i want a new s3 but i am not jealous honest

 

[RobM]

Cheers for your advice

It's frustrating, as I don't know enough about these engines yet and I don't have access to the space or tools to check things myself! Car's booked in with JKM for Thursday this week (assuming I can get time off work) so hopefully they will find the problem, but I'd was hoping to be able to sort it myself

 

[richybigman]

You gonna get it rolling roaded whilst you're down there?

 

[Ruddmeister]

When I had similar issues I ended up having to take mine to a rolling road centre so it could be tested under load. Dealers seem tostruggle to resolve these kind of issues that relate to pipe leaks as they don't leave a clear and indicative fault code.

Was that Stealth? assume they sorted the car for you?

 

[RobM]

You gonna get it rolling roaded whilst you're down there?

Possibly. They are going to do a physical check first to see if they can find the problem, but if they can't it will go onto the rolling road. If they manage to find and fix the problem and they have the time, I will ask for a rolling road run to see if it is making it's correct power.

 

[Mitchy]

Without stating the obvious, an underperforming 1.8T is usually down to an under reading MAF sensor.

Usually the 1st thing you should check.

I had similar problems when i first got my LCR. I changed the MAF and it made a huge difference to the performance.

What kind of fuel are you putting in? Try V-power 99 for a few tanks.

My car just doesnt like Esso/BP 97. It is noticeably more sluggish and less responsive compared to the V-power fuel.

Have the sparkplugs been changed? 40000 mile service and they should be replaced.

Dirty airfilter?
Boost leak (Cut/torn hose)

The temp sensor is renound for going wrong and it can also have an effect on performance. Do you have the green topped bosch sensor?

 

[RobM]

Without stating the obvious, an underperforming 1.8T is usually down to an under reading MAF sensor.

Usually the 1st thing you should check.
Logs seem ok (once I worked out how to get accurate logs). Did try unplugging it and taking it for a drive and it was great. Plugged it back in and it was also great, so no difference.

I had similar problems when i first got my LCR. I changed the MAF and it made a huge difference to the performance.

What kind of fuel are you putting in? Try V-power 99 for a few tanks.

My car just doesnt like Esso/BP 97. It is noticeably more sluggish and less responsive compared to the V-power fuel.

Started using VPower, now using Tesco 99RON as the car seems happier on it.

Have the sparkplugs been changed? 40000 mile service and they should be replaced.

Had full service 5k miles ago, is due for another in 5k miles time.

Dirty airfilter?
Air filter is spotless

Boost leak (Cut/torn hose)
Booked in with JKM to find this out. But would expect a boost leak to be evident all the time, not just some times?

The temp sensor is renound for going wrong and it can also have an effect on performance. Do you have the green topped bosch sensor?

Only started thinking of Temp sensors this morning, so will check tonight. But as I mentioned in original post, I think this problem may be heat related as it occurs most after idling for a while or crawling along in rush hour traffic.

Answers in Bold above to make life easy