Performance problem. No boost....?

[RobM]

My car seems to have an odd, intermittant performance problem and I wondered if anybody could shed some light on it for me?

Twice since I've owned the car (a week) it will perform like the turbo has gone to sleep. You can't hear the turbo spooling up, and the car feels like a normal 1.8 car, there is no boost and very little performance compared to normal.
When this happens, it seems that turning the car off and leaving it a while cures the problem (heat related perhaps?)

Now I don't know if this is related, but last night it happened after I was sat outside waiting for someone with the engine running. I must have been there for 5 or 10 minutes tops. On the way it was fine, felt great. On the way back, after that wait, it felt like the performance had gone totally. It still drove smoothly, but just like a decent N/A 1.8 would feel.
I can't remember for sure, but I have a feeling the first time it happened was also after sitting for a while too... but can't be 100% sure.

Does anybody recognise these symptoms? Is it something stupid that I need to be aware of (it's my first turbo'd car) or is it sounding like a more serious problem?

Any help would be appreciated

Cheers

Rob

 

[BEOWULF]

could be ya dv
or a pipe have a look round the turbo area m8 c if u can find any residue
do u now any one with vagcom.

 

[RobM]

Unfortunately I don't know anyone with VAG-COM. Would be handy right now.

I've had a good look around the DV area and all pipes and connections seem nice and tight. No sign of anything out of place, that's for sure.

 

[BEOWULF]

what dv do u have is it the bosh one

 

[RobM]

Yes it is, car is totally standard.

 

[emocionR225]

Check my thread on this very page mate.

All I can say is...good luck.

 

[RobM]

Check my thread on this very page mate.

All I can say is...good luck.

Just had a read mate, sorry to hear of your problems

I don't think the problem is the same as mine though. I've driven the car nearly every day, including stop-start driving in traffic on the way to work and it's always been fine. It's just these two occasions where the problem has occured.

I hope you get yours sorted though, hopefully the fault codes will help Seat shed some light on the problem.

 

[cupra-c_ya]

any light on the dash? could be your maf fella, car would not pull so well if your maf is failing or died.

maybe someone near u in southampton will lend a hand with vag com?

you could un plug your maf briefly to see if your car performs better, this might give you your answer

 

[RobM]

If the MAF was failing, would this not happen all the time though? I'm going to look into this VAG-COM business and see what's needed to get it going.

 

[cupra-c_ya]

sorry just noticed you said that it is intermittent, as already said worth checking all pipework, d/v. Standard boash recirc valve is crap and can fail on a standard car, these are areas to look at but vag com might tell you more as you may have fault codes.

If you have a laptop and you are interested in getting a good third party interface cable for vag com send me a pm.

 

[CupraUK]

I had the same thing when the connector on my N75 valve was loose

 

[RobM]

I had the same thing when the connector on my N75 valve was loose

Interesting... was this under the same sort of situation? I mean, in your case, what caused this problem to happen?

 

[RobM]

I've just spent a while reading about the N75 valve, and this does sound like a possible cause.

Is it possible that by letting the car idle for 5-10 minutes, the N75 got stuck open and effectivly caused zero-boost? Turning the engine off and letting it cool a little could then have allowed it to re-set? Or am I talking nonsense?

Also, despite finding loads of information to read, I've found no pictures of the N75 and where to find it in my engine bay. I'd really like to check this out tomorrow and ensure everything is attached properly. Does anybody have any pictures or guides that may help?

Cheers

 

[cupra-c_ya]

this is what you are looking for, under the engine cover.

 

[RobM]

Nice one, just found that part on the VagParts website. After reading more about the N75, it seems as though fitting the later spec'd 'J' version may help performance too.

But I'd still like to shed some more light on my original problem if possible.

 

[cupra-c_ya]

N75J can cause probs mate, limp mode etc. Some people on here have used it and not had any probs.

 

[CupraUK]

Yes, don't assume that the N75J will suit. Go for a standard F replacement first to check if solves your problem. Don't comlicate things while you have a problem by trying something new.

When I had the problem it was just literally a loose connector, when I got revo it failed completely but I still replaced with a standard before moving to the J later on as I like its delivery rather than its performance benefits.

 

[cupra-c_ya]

Well said cuprauk

 

[Ruddmeister]

Nice one, just found that part on the VagParts website. After reading more about the N75, it seems as though fitting the later spec'd 'J' version may help performance too.

But I'd still like to shed some more light on my original problem if possible.

Before you spend money on the N75 identify the issue, if the car is dropping into limp mode which is what it sounds like then there will be a code or three logged on the ECU. You need to get the codes read and this will shed some light on the problem. The issue could be heat related as you say, could equally be a faulty sensor or something else altogether.

When you have the codes look in the VAGCOM section and match the code to the problem.

Sometimes the code doesn't always give an obvious answer so if you have a query post a question in that section when you get the answers.

 

[RobM]

Nice one guys. I was going for the 'two birds with one stone' idea in replacing a faulty part with an uprated version.

I've ordered a VAG-COM cable and will download the software when that arrives. When all is done I'll see what fault codes are logged.

Quick question though... are all fault codes logged and stored, or do they go away if the problem corrects itself, so only current codes are shown? Reason I ask, is as this is an intermittant problem, do I need to wait until it happens again before running VAG-COM?