Mr2 Mk2 2 Turbo not making any boost or revving past 3-3.5k.

[moscoworbust]

Hi,

I have a rev 1 turbo and I have a problem.

I was driving down the motorway and accelerating and the boost was coming on and off and the suddenly I couldn't make any boost and I couldn't rev past 3-3.5k.

I thought that the wastegate was stuck open or the turbo had seized.

So today I took the whole intake and exhaust system apart.

The wastegate was shut and the actuator is fine, even if it was't and was stuck closed it would be over boosting. Plus the actuator arm moved fine when I opened the wastegate with a screwdriver and it closed.

The turbo isn't seized. The impeller moves fine and the shaft on the turbine side moved with it.

I checked all the intake lines for a split, and no split, so no air leak.

It is very weird.

I will reset ECU tomorrow.

Ideas?

Clogged air filter? Can't be, it's a mushrooim filter with loads of gaps.

Blockage? Maybe in the exhaust but I have a huge japspeed one. I'll check this?

Fuel? Might be a blocked fuel filter? I can check this tomorrow.

Any help appreciated.

Thanks.

[eybic]

I've had similar in my Celica when the intake pipe came off, I would say there is definitely an issue in getting boost to the intake somewhere.

Have you run the car since putting it back together?

[TankRizzo]

Boost is load-dependent, isn't it? Have you checked that the throttle body butterfly moves freely?

[moscoworbust]

Hi,

yes I'm still driving it.

It drives fine.

No split on the intake side of the turbo.

MAF works fine.

Throttle body moves fine.

Fuel is load dependent off MAF not throttle body.

[Stuartggray]

Check any silicon/rubber bits under vacuum at speed for collapsing.

[moscoworbust]

re. Check any silicon/rubber bits under vacuum at speed for collapsing.

did that.

revved it and checked actuator wasn't moving too.

Think it might be ECU issue.

But the violent coming off and on boost before it happened makes me think it's mechanical.

[MikeyMike]

You'll probably get a better response on imoc.co.uk but it sounds to me like you've either hit fuel cut or blown the knock sensor. The knock sensors on the early turbos at least (I have a rev 2) are pretty much disposable items, I've gone through about 3 in 8 years.

Check for error codes before you reset the ECU.

[moscoworbust]

Flap in MAF is fine but still might be a knackered MAF.

[moscoworbust]

RE.

"You'll probably get a better response on imoc.co.uk but it sounds to me like you've either hit fuel cut or blown the knock sensor. The knock sensors on the early turbos at least (I have a rev 2) are pretty much disposable items, I've gone through about 3 in 8 years.

Check for error codes before you reset the ECU."

Guys on IMOC are thieves, cowboys or idiots.

I removed fuel cut.

The knock sensor sends ECU into limp mode?

I'll check ECU codes tomorrow.

[TankRizzo]

The only thing I can say is that I used to have a similar thing on my VX220 Turbo and it was the plugs, but it ran like a bag of spanners with the ECU light flashing until I fixed it (went into limp-home).

That almost sounds like the ECU cutting boost to save the engine when it's leaning out, does the MR2T ECU have that type of protection?

[ejenner]

Turbo is broken.

[moscoworbust]

"The only thing I can say is that I used to have a similar thing on my VX220 Turbo and it was the plugs, but it ran like a bag of spanners with the ECU light flashing until I fixed it (went into limp-home).

That almost sounds like the ECU cutting boost to save the engine when it's leaning out, does the MR2T ECU have that type of protection?"

Plugs are fine.

No, the way I have it set up, the boost is only controlled by my controller. The ECU has no control over it.

ECU only controls fuel and ignition ( via a distributor)

So fuel only.

[moscoworbust]

"Turbo is broken."

It isn't.

[MikeyMike]

Yeah if your knock sensor has gone pop your car will go into limp home mode which is very much like the symptoms you've described, and you will get an error code. New knock sensors are bloody expensive though so unfortunately it's not like you can just chuck one on in the hope it fixes the problem, need to get the code or test it first.

Good luck with it.

[moscoworbust]

"Yeah if your knock sensor has gone pop your car will go into limp home mode which is very much like the symptoms you've described, and you will get an error code. New knock sensors are bloody expensive though so unfortunately it's not like you can just chuck one on in the hope it fixes the problem, need to get the code or test it first.

Good luck with it."

Cheers.

Sensors are 35 quid, not too bad.

[Herman Toothrot]

moscoworbust said:

Guys on IMOC are thieves, cowboys or idiots.

Sounds about right, a decade ago it was a great forum I gave up on it about 5 or 6 years ago, was by that time more populated with chavs than normal people.

[ejenner]

moscoworbust said:

"Turbo is broken."

It isn't.

Did you check if you still have a turbine wheel?

[moscoworbust]

ejenner said:

id you check if you still have a turbine wheel?

Yes, when I span the impeller wheel I could feel the shaft moving on the turbine side.

The turbine wheel is so deep inside the turbo I couldn't actually feel it or see it.

I think if the turbine wheel had snapped off there would be oil everywhere and the debris would of ended up in the engine and I wouldn't be able to drive it.

I'll try the fault codes tomorrow.

I don't want to take the turbo off but I will if I run out of options. Might upgrade to a ct20b.

[GC8]

Its usually a vacuum pipe.

[moscoworbust]

ejenner said:

moscoworbust said:

"Turbo is broken."

It isn't.

Did you check if you still have a turbine wheel?

Ah crpa, you've got me second guessing myself now.

This is what you are talking about:

http://www.mr2turbo.info/brokenturbo/

Maybe I could just feel this centre part spinning and the turbine should of been there.

Should of taken a photo.