leon 110 tdi lack of boost?

[bigdaddy]

I have done research previously to posting this thread into why i might be getting lack of boost for example MAF/MAP sensor, sticky turbo rings etc but i just want someone to help me out which would more than likely fit my situation so i know where to start.

Basically earlier today i was driving up the dual carrage way and started to overtake another driver. I put my foot down through 3rd and 4th gear taking it to around 3000rpm before changing gear to get past. When i was safely past the driver I put it into 5th gear and as soon as i took my foot off the clutch i had a huge dip in power (slight up hill dual and with my foot to the floor the car wouldnt accelerate at all). I then changed back down into 4th and was getting the same problem.

It turns out I was getting a complete lack of boost in any gear (it was for all the world like i was running on the diesel engine alone). I stopped the car to listen if i could hear the turbo spooling and it was but it was alot more difficult to hear than normal. At no point during any of this did the engine management light come on but i decided to take it to my mate who has a diagnostic machine and all the readings on the machine looked fine as well as there being no error codes present.

I drove it around half an hour ago (around three hours after the whole thing started) and the problem seems to have fixed itself with the turbo giving full boost and all the power is restored. Ill be doing alot of mileage in the next few weeks and i need to get whatever the problem is sorted ASAP to avoid breaking down.

If anyone can give me a headstart as to which problem it could be ill get right on it. I appreciate any help and thank you in advance

 

[sssstew]

its strange that nothing got logged, but it certainly sounds like limp mode which will be because of boost i reckon. I would bet on sticky vanes on the turbo, drop it off and clean it up or use some innotec then report back.

 

[akchappers]

Or rag the crap out of it!
Ak

 

[MrBen2k7]

I have done research previously to posting this thread into why i might be getting lack of boost for example MAF/MAP sensor, sticky turbo rings etc but i just want someone to help me out which would more than likely fit my situation so i know where to start.

Basically earlier today i was driving up the dual carrage way and started to overtake another driver. I put my foot down through 3rd and 4th gear taking it to around 3000rpm before changing gear to get past. When i was safely past the driver I put it into 5th gear and as soon as i took my foot off the clutch i had a huge dip in power (slight up hill dual and with my foot to the floor the car wouldnt accelerate at all). I then changed back down into 4th and was getting the same problem.

It turns out I was getting a complete lack of boost in any gear (it was for all the world like i was running on the diesel engine alone). I stopped the car to listen if i could hear the turbo spooling and it was but it was alot more difficult to hear than normal. At no point during any of this did the engine management light come on but i decided to take it to my mate who has a diagnostic machine and all the readings on the machine looked fine as well as there being no error codes present.

I drove it around half an hour ago (around three hours after the whole thing started) and the problem seems to have fixed itself with the turbo giving full boost and all the power is restored. Ill be doing alot of mileage in the next few weeks and i need to get whatever the problem is sorted ASAP to avoid breaking down.

If anyone can give me a headstart as to which problem it could be ill get right on it. I appreciate any help and thank you in advance

My old 110 did this, new MAF cleared it for me.

But I'd give it a good italian tune up, wack it in 3rd and redline it until the black smoke stops.

 

[Lancashire Lad]

Does that work? I have only ever seen black smoke from mine when it was on the rolling road at awesome gti (during the remap

 

[MrBen2k7]

Gets the turbo and exhaust hot enough to clear out the carbon deposits and frees everything up.

Try that or some good fuel treatment.

 

[akchappers]

WHat he said.
Ak

 

[bigdaddy]

hey guys.

I decided to take your advice and i tried redlining it in third gear to clear the turbo however as soon as i hit 4500rpm the car went into limp mode again. I kept it on the redline for around 3/4 of a mile though to see if it made an improvement. I pulled over after, shut the engine off and started it again and the power was back.

Anymore ideas on what it could be with this info?

 

[MrBen2k7]

MAF I'd say, mine did the same when this happened.

 

[bigdaddy]

Aii i was thinking more along these lines to be fair.

Reckon i would have any luck with cleaning it?.

 

[sssstew]

sure, give it a clean and see if it makes any difference, if it does then you know that your maf is on the way out. if a maf has got to the point where it needs cleaning then usually its on its last legs and needs replacing.

 

[bigdaddy]

Hey guys,

Sorry its been a long time since i last posted, had alot to do over the previous weeks.

I cleaned the MAF sensor today and took it for a little run it appears to be little to no difference in the power of the car etc. although i couldn't manage to get it into limp mode today. It is hot and dry here though and the problem seems to occur more when the engines cold and its been raining.

Anyway while cleaning the MAF sensor today i noticed that there was an oil leak towards the front of the engine so i took the engine cover off and noticed that the leak was coming from a pipe on the top of the engine which is connected to the thick air intake pipe which the MAF is connected to on the right hand side. The part connected to it is circular located directly on the top of the engine and looks like it is a pressure release valve of some sort. I undid the pipe and had a look inside and there is definitely oil in the pipe and well as oil going into the intake pipe.

Would this cause my limp mode problem?

Cheers

 

[SEATgod]

Hello Mate, that is your breather pipe.

If the control valve is damaged it "could" cause your issue by allowing unmetered air to be drawn into the engine.

It does sound like your turbo vanes are sticking...so common on these engines.

Do you have vacuum gauge (miti vac or similar)?

I can talk you through checking it if you do!

If not where do you live? I might be able to help if your close!!

An air mass fault will cause a lack of power but not limp home mode as the ECU use a base value to fall back on if it reads erratically etc.

Limp Home mode is normally caused by overboost! Got an engine light on?

TTFN

 

[bigdaddy]

No i haven't got a miti vac sorry mate however there are no fault codes on the diagnostic machine.

Something i however forgot to mention is i have a noise coming from the behind the center console which hardly happens but when it does i can feel the engine lose power for the length of the noise which normally lasts for the whole of half a second and this can happen about 3-4 times then stop and i wont hear the noise again for a few days. It started happening just as i took my foot of the clutch after changing gear but did occur once when i was in gear around five seconds after changing although hasn't happened like that again.

Sorry if the informations limited but i've never heard this sort of noise in the past but if i was so hazard a guess it would sound either like grinding or a sucking of some sort but dont quote me on it.

One thing that might be worth mentioning is that im not positive that the car is going into limp mode but due to the explanations of other users in to what limp mode is, it does sound very similar.

i live in south wales by the way buddy. Near newport.

Cheers

 

[aymen_a22]

Hi,

I have a 110 TDI SE (ASV engine) and have had the exact same problem as you and I tried everything to fix it including the 3rd gear high rpm fix and it did not work.

The problem is the rings in the turbo for the VNT system, they are clogged up with carbon and are not allowing the turbo to reduce boost pressure which is giving an engine code and putting the car into limp mode. Cycling the ignition will solve the problem temporarily until you need the higher boost levels and then the engine will go into limp mode again.

To solve this problem I got underneath the car and took off the engine tray, you should be able to see the VNT actuator on the back of the turbo, get your hand up there (when the engine is dead cold) and pull the actuator, it should move about 18mm. If you have trouble moving it then you will know this is the problem.
Another test is to disconnect the vacuum line from the N75 valve (on the bulkhead) and suck that. Look down the back of the engine and once again you should see some movement of the actuator, if there is no movement then it is clogged up.

There are a couple of solutions to cure this problem.
1: Innotec Turbo cleaning Kit - Involves removing the exhaust at the turbo and fulling with various solutions which dissolves the carbon and then neutralizes the metal.

2: Remove the turbo from the car and open it up and clean the insides.

3: Crude method but it worked for me, remove the EGR pipe from the car, get some mr muscle oven cleaner and using a small tube fill the turbo as best as you can. Leave the cleaner in there for maybe 15 mins and actuate the VNT mechanism by hand (or with a screw driver from the top) until it is free. Now get some engine de-greaser and put that in the same tube. Once completed reconnect the EGR pipe and start it up, warm the engine up and then get the turbo spinning a little. Lots of black smoke will come out and that should be the problem solved.

Your choice. Good luck

 

[bigdaddy]

I was looking at that innotec cleaner and apparently you need something behind the cardboard they provide to stop the cleaner coming out because it's "useless". This true?

 

[aymen_a22]

Yes that is true, the kit should come with a piece of cardboard but apparently that is useless and it is better to use something else (make your own).

 

[bigdaddy]

alright thanks mate. Ill give it a try and let you know how it goes

 

[aymen_a22]

Good luck with it, I think you will need to renew the gasket between the turbo and exhaust so I would make sure of this before you start. Also the bolts will probably be very very difficult to get off so it might be worth soaking them as they could be quite brittle after the heat cycles it experiences.

 

[bigdaddy]

I know this might not be associated with the limp mode problem however how serious is the leak from the breather pipe?