Turbo Back Pressure

[Joe Flannigan]

Hi Peeps

Yes I am a New

I have a Toyota Avenis 2.2 L Diesel 2008 Model (180 BHP)

Well where do I start..... The head gasket went first and had this fixed with a new water pump. The car was running fine, then the Battery went pop on me and replaced the Battery. I then started to see black smoke coming from the exhaust so had the erg valve replaced and still had the black smoke and loss of power from the turbo. There is also back pressure coming from the turbo this builds up near the Throttle housing next to the inlet manifold. I have now changed the throttle thinking it was this causing the problem(No Fix) There is no power and just get back pressure, although when I take of the pip leading gate valve to the turbo drop fuel the pressure is gone and don't have any power. I have had the turbo checked and I was told the turbo is fine although, has a little play in the turbo. I have also been told it could be the ECU electrical fault. I don't want to get rid of the car as it has everything I want in it and drives like a dream when fully working.

The engine management light is now on with VSC and Traction control light.

Can anyone help!!! I am at my wits end and have spent £1800 in the last three months.

Thanks

Joe

[Heidfirst]

when you had the head gasket done what exactly did they do? The head gasket often goes as a result of carbon build up internally so if they didn't address that it will only go again & with possible additional damage. The Toyota fix under warranty was essentially a new engine (minus ancillaries) on an exchange basis - £5-6k at retail!

Is it using oil?

[Joe Flannigan]

Hi Scott

Thanks for the reply.

There was a build of carbon and all was cleaned thoroughly. There is no oil burning it is all carbon black smoke. I was not entilted to the warranty as the car has 140000 miles on the clock.

It is driving me crazy as it just seems to build up pressure until I un-plug the pipe going into the gate valve. The engine is running really smooth till you put your foot down and there is no turbo kicking in with the gate valve attached and without. I would dread taking it to Toyota as it would cost me a fortune.

Just looking for any ideas to check.

Joe

[Cyker]

What do you mean you have turbo back pressure?


Normally when you talk about back pressure, it's concerning a blockage in the exhaust which saps power from the cylinders as they have to push against this back pressure instead of having a free flow.


What is the problem you're trying to fix exactly?

Is it that you're getting a lot of smoke under acceleration and there is a lack of power?

That can be caused by turbo problems; I'd check for damage or leaks in the pipes/hoses. If you have a variable turbo, might be worth getting it checked to make sure the vane actuator is moving freely.

Other causes can be a sooted up EGR and/or throttle body. The throttle body in particular can be prone to this as there is a small channel that goes from the EGR to it and it gets so sooted up you wouldn't even know it was there if you looked at it!

I had that on my Yaris once; My travelling mechanic mate soaked the thing in carb cleaner until it all dissolved revealing a 5p-sized hole which was completely hidden before

[Mr.D]

Hi,

I would start from simple things and go to heavier on money and labour, starting from:

1. Fuel filter, either way it is good to change it.

2. Turbo leaks, this can be checked one of 2 ways, either smoke machene attached to inled or... smoke from your mouth ( most probably you'll have to borrow one cigarette).

3. Actuator, this might be stuck and variable turbo isn't variable anymore.

4. MAF sensor, it is between turbo and air filter, cleaning with something very vapour active ( dries fast) and soft brush ( like kids uses).

5. EGR check and clean, easy to do, might be difficult to get it out.

6.Check fuel preassure in rail, however in this case there would be a noticable but not total loss of power.

I would leave ECU as absolutely last option possible.

[avensisd4d786]

I have never had my hands on the 2.2 but look at the map sensor and boost sensor. these sometimes give trouble on the 1cd engine

[Joe Flannigan]

I have now had all the electrics checked by auto electrician and all is working fine.

The smoke has now stopped and the back pressure from the throttle housing has stopped since I have taken off the pipe from the gate value.

I have no power although the engine is running like a dream.

I have gone through and checked the ideas from the people who have posted comments. I would like to say thank you.

The next thing I am going to try is to change the vacuum valve solenoid to see if this will fix the problem.

Please post any comments as I will take them all on board to fix this issues that is driving me insane.

Joe

[avensisd4d786]

What are the fault codes when engine management light comes on?

[Joe Flannigan]

Hi

I have no engine management lights on.

This is where I am up to at the moment. I have a whooooshing noise when the pipe is connected to the gate valve coming from somewhere near the inlet manifold. When I release the gate valve by removing the small pipe it goes away but have no turbo power. I can hear the pressure build up, when I turn off the engine you can hear it release.

I have been driving the car without turbo and drives really good but no power.

I have tried changing the solenoid connected to the gate valve still no different.

I have tried all the above tips and still no joy.....Please help its driving me crazy.

Joe

[Cyker]

Could there be some debris blocking a pipe somewhere? (I really have no idea!)