Car not boosting past 3k! - Solved!

[dj_troopa]

Hi all

My car problem went from overboosting in 3k-4k but now it won't even boost past 3k!

Foot down for boost to kick in, you can hear the filter sucking as normal, hits 3k, then boost just dies! It's like you putting your foot down then wacking it into neutral, there's just nothing past 3k. If i keep my foot down when this happens it looks like it will take a lifetime to build up any power after 3k. Definitely jumping into limp mode but i don't know why

There's no EML but i'm getting it scanned by a friend tonight. Has anyone else had this issue or have any suggestions to what i can look at? Even though there's no EML, i REALLY hope it comes up on the scan tonight!

Thanks all

 

[Dan FR]

You don't need a scan, you need data logging with VCDS.

Sounds like a fuel supply issue to me.

Get it on VCDS with someone who knows what they're doing with it. Log both the High pressure and low pressure side of the fuelling, monitor boost, timing pull, lambda correction, misfire count etc etc.

 

[mike0105]

Have you checked the diverter valve?

 

[dj_troopa]

You don't need a scan, you need data logging with VCDS.

Sounds like a fuel supply issue to me.

Get it on VCDS with someone who knows what they're doing with it. Log both the High pressure and low pressure side of the fuelling, monitor boost, timing pull, lambda correction, misfire count etc etc.

Cheers Dan. I need to find someone local and good with VCDS.

Have you checked the diverter valve?

Nope not yet, been thinking about the diverter valve too. I purchased a Rev D in May/June time this year.

 

[Dan FR]

Is it misfiring too, or just flat and sluggish? Diverter valve is a strong contender too, but impossible to say without logging.

Even getting the app 'Torque' and a bluetooth OBD device would allow you to monitor boost, fuelling etc if you don't have VCDS.

 

[dj_troopa]

Nope no misfire. Boost just disappears at 3k and if you keep your foot down the rev needle and mph needle hardly moves, gets caught in limp mode.

I've got the Dash Command app but it's crap, always given me wrong readings even after playing with the settings. Would rather have something proper like VCDS to carry out any scanning/logging.

I ordered a new cam follower from Dave @ Sere this morning just because i want to change it anyway. If i remove my Rev D, how can i tell if it's crapped out on me?

 

[aaronb84]

Deleted

 

[mike0105]

Take it out and have a look. Here is an exampe of a knackered one http://www.audi-sport.net/xf/threads/diverter-valve-fail-images-2-0-tfsi-quattro.171340/

 

[dj_troopa]

Thanks will have a look tonight when i'm home from work. Mine is the Rev D which is the plastic one so will check for any damage to it. I hope it's something simple to sort out!

 

[dj_troopa]

Update:

NO FAULT CODES FOUND.

Now what!? depressing times.

 

[Dan FR]

Logging......

 

[mike0105]

A dv won't always throw a code, you would log some data to find out what it is, as Dan mentioned earlier.

 

[dj_troopa]

Just checked the DV and it looks fine. Yellow ring around it is perfect no splits. Piston moves up and down freely like when i first bought it.

Dan - Yeah will have to find someone local with VCDS and log it. Can't even drive it 'properly', have to granny drive it under 3k everywhere. Will keep this updated as i go for others reference.

Thanks for the input all. Anyone have any suggestions feel free to post But will have to get it logged to pin it down as Dan advised. Would just be nice to have some kinda rough idea.

 

[Joshkcupra]

Troopa, where abouts in London are you? I'm in Kent and have VCDS

 

[dj_troopa]

Troopa, where abouts in London are you? I'm in Kent and have VCDS

I'm in Hayes like 10 mins from Heathrow so a bit far

 

[dj_troopa]

Going to the garage tomorrow who fitted my intercooler. As they are remap dealers they use VCDS to log cars when mapping. He said to pop down and will see what he can find wrong with the car.

Looking forward to it! Hope its not something too expensive lol.

 

[Dan FR]

Get some full throttle logs of the most important data and post it up here

This guide from APR is useful to help with what to log

http://www.goapr.co.uk/support/datalogging.php

 

[dj_troopa]

Great, cheers Dan! That was gonna be my next question. Hopefully he already knows what to do anyway but i'll keep this in mind just in case

 

[locky]

Get some full throttle logs of the most important data and post it up here

This guide from APR is useful to help with what to log

http://www.goapr.co.uk/support/datalogging.php

Cool guide, thanks for that!

 

[dj_troopa]

Update:

I popped down to the garage yesterday for VCDS logging to investigate my issue.

As i'm Revo'd and have the SPS controller, he asked if i could switch the car back to 'Stock' mode to see what happens. What happens? The car bloody drives fine in stock mode! Many logs were taken in stock mode and performance mode (which are my proper map settings) and it wasn't showing any issues. Strange!

He then carried out a smoke boost leak test. Smoke was shooting out fast from the corner of the MAF sensor. The MAF sensor seal which goes around it on the inside was loose and obviously wasn't working very well. There was also smoke coming out of the dipstick. This was due to a small o-ring seal on the dipstick which slid off but he put it back on again and there was no more smoke. Lastly a boost leak coming out of some vacuum pipe which is clipped to the front middle of the rocker cover. Unclipped and clipped on again and there was no more smoke. He's getting me a gasket seal next week for the MAF sensor and that will be the end of boost leaks for now.

Last night i was doing more research online and came across a Revo mode called 'Valet' mode. Valet mode will limit the RPM to 3.5k which cuts of boost so basically noone can rag your car if you hand it someone. So the car works fine in stock mode, alot less power but drives spot on. In performance modes the car is limiting at 3.5k. I also seen a few people on other forums had problems with their Revo and chucking them into valet mode for no reason. Revo say to put car into stock mode then performance mode and it will all be back to normal. I've tried this and it hasn't worked. Others who had this issue went to their Revo dealer and had their ECU flashed which cured the issue.

I think a call to my Revo dealer first thing tomorrow is on the list! We're slowly getting there