Clogged Catalytic Converter

[carlo1s]

Hi all from Venezuela,
I have a Zd30 engine that not start because the catalytic converter is clogged and I must wait at least 3 months to get one from my dealer, they haven´t in stock.

So I am wondering if I could remove the converter without have problems with the engine.

I read in this topic that 2006 D22 ST-R 3.0 ltr, don´t have catalytic converter..

Thanks..

 

[Dave]

Rip it out or get a aftermarket one.

The ZD30 ECU isn't that smart to register that its been removed.

 

[Old.Tony]

The catalytic converter is an emission control device, nothing more. You can remove it, but run the risk of being fined for not having it in place.

Chances are, nobody will ever know unless you paint on the side of your car "I have removed my CAT".

 

[carlo1s]

Thanks guys. In Venezuela We don't have emission control test.

Is true 2006 Zd30 ST-R don´t have cat?

 

[Dave]

Not sure about over your way mate.

But they do out here in Australia.

Just delete it until you can get one, I am no greenie but the cat is one thing I personally would keep on the vehicle.

 

[tweak'e]

Thanks guys. In Venezuela We don't have emission control test.

Is true 2006 Zd30 ST-R don´t have cat?

just rip the cat out and fit dump pipe. upgrade the whole exhaust while your at it.

some markets have a different emissions setup than most of the ones down under have. i've seen pics of one without egr butterfly.

also i would find WHY the cat blocked up. typically bad fuel, poor injectors, clogged intakes, to much engine oil through the breather can cause the cat to block up.

 

[carlo1s]

I am going to rip it out this weekend.

the cat block up becouse the turbocharger was leaking oil for a long time!

 

[DieselTuner2]

Wow, even with a leaking turbocharger I have never seen a cat blocked badly enough to prevent an engine from starting.
It must have become impossible to drive the vehicle due to lack of power?

 

[carlo1s]

yeah my car was losing power until one day was imposible start it. I had to change the turbocharger due it had a lot of soot petrified on the dump pipe and turbine of turbo..

But after that my car won´t start. the air can´t pass for the cat is totaly blocked.

 

[Old.Tony]

I'd be concerned about the oil leak. Are the turbo bearings shot? Check the shaft, it should spin very freely and not wobble in the slightest - if it does, bearing failure will soon be followed by turbine failure and catastrophic destruction of the compressor. These should be caught by the intercooler ... but why not avoid that?

A good question is: why are the bearings failing? The most common reason is early shutdown, where the turbocharger is still very hot but the engine is turned off. Once the engine stops, the oil pump doesn't move oil through the bearings, so the oil that is in there starts to cook from the heat. It produces varnish, a hard substance that will deform the bearing's surfaces and destroy them.

If you are shutting down early, you might want to invest in a turbo timer or at least an EGT gauge so you can see what the temps are before you turn the engine off.

 

[carlo1s]

Old.tony...! I changed my turbocharger due all that you are telling. It was in very bad conditions. I think it was by early shutdown. I didn´t know that until I had to buy a very expensive new one

 

[tweak'e]

an exhaust blockage causes more egr to be shoved into the motor. that makes it smoke a whole lot more which blocks up the cat even more.
i've seen pics of a patrol ZD30 cat all blocked up and it was without a leaking turbo.

 

[Old.Tony]

Old.tony...! I changed my turbocharger due all that you are telling. It was in very bad conditions. I think it was by early shutdown. I didn´t know that until I had to buy a very expensive new one

Glad to hear that you caught it in time! If there is no intercooler, the engine will be ruined by the broken parts entering the cylinders and being rammed by the pistons just as the engine siezes. Rebuild costs would be several thousand dollars at least.

Now it is time to get an EGT gauge and watch the temperature! Put the probe BEFORE the turbocharger on the exhaust manifold. Wait until the temperature there is under 300C at least before you shut down.

 

[Escapee]

What about the cat in the D40 diesel 2006/7? Can that be replaced with a cheap aftermarket one. Reason I ask is my turbo is blowing back through the intake and without taking it apart yet the mechanic suggests this could be caused by the cat being clogged causing too much back pressure. So end of the day I'm defeinately needing a new turbo and I'm now looking for the cheapest option for a cat if worst comes to worst and I need to replace that too.

 

[Old.Tony]

I don't understand "my turbo is blowing back through the intake". I do NOT see how a clogged CAT will do this.

The intake side of the turbo is in NO way connected to the exhaust side. You could fill the exhaust with spuds and the exhaust isn't going to come out the intake side of the turbo. You'll stall the engine and/or fire lots of baked taters at the car behind you but that's all.

If your CAT is clogged it may degrade the vehicle performance but it shouldn't cause issues with the turbo. An aftermarket CAT may be available and should resolve the problem, but if you suspect the CAT is blocked, you could just use a screwdriver to hollow it out and see if that fixes it.

 

[Escapee]

Just going off what the mechanic said and he "thinks" something inside has given way. There is carbon build up around the inlet seals and when he removed the airbox he could feel pressure blowing back when I reved and let the throttle back off.

Aside from the cat' converter the problem started when I noticed a strangled cat sound coming from the turbo on acceleration with a tone that matched the engine RPM. Took it to 1 mechanic who straight out said the turbo bearing is on the way out due to a noise it makes on engine shutdown. Second mechanic agreed and pointed out the carbon build up. either way I need a new turbo but the concern is what caused it to fail at just 120,000 kms. 1st mechanic said cause the exhaust manifold gasket was blown and letting crud in. That didn't make sence and second mechanic who is an exhaust specialist said manifold gasket is fine but suspects that the cat could be blocked and would require inspection to confirm but that hte back pressure caused by this "may" have blown out something inside the turbo.

 

[tweak'e]

i would suspect the vane system is jammed or not working.
quite common for the control solenoid to fail and the turbo stays in one position. also the vanes are known to stick in one position.

the turbo could be stalling due to lack of drive when you take foot of the gas and you get bit of boost coming back through. especially if you have the model that has the variable inlet butterfly.

 

[Old.Tony]

If you're hearing a squealing sound coming from the turbo, it's either the bearings making the noise directly (softer sound) or the compressor wheel rubbing the housing (really loud sound).

Either sound is terminal for the turbocharger - it's gone.

The cause for bearing failure is usually as I posted previously in this thread (and plenty of times elsewhere) - the engine is turned off before the turbocharger has cooled enough, so the heat still in the turbo cooks the oil that just sits in the bearings.

Change the turbo, problem's gone, but it could happen again unless you look after your turbocharger.

I'm going to make a thread about "Caring For Your Turbocharger" - I've been writing it for some days now, and when I think it's ready I'll put it up.

 

[Krankin]

Last time I had a complete cat failure and full blockage, I removed that small section of pipe/cat section and with a meter or so of 90mm2 XLPE SDI,
used that to shove into the cat and removed the whole blockage, then put the section back in and hey presto...a new ex system with cat and all looking standard.