High Street Mechanics Bricked My Car

jgradisher

Mildly_Miffed said:

jgradisher said:

born_again said:

I'm curious by just what a "High Street Mechanic" is?

Begins with an H. But I am reserving official calumny until this all settles

You took it to a bicycle shop?

Yes, I know...

LightFlare

jgradisher said:

born_again said:

I'm curious by just what a "High Street Mechanic" is?

Begins with an H. But I am reserving official calumny until this all settles

I would barely trust them to fit a wiper blade let alone do a cam belt change 

Ibrahim5

I like the bit about trying one belt and then another one. You can only muck the timing up. I would always use the best belt possible but if the belt is turning it's obvious that you've messed the timing up. Changing the belt isn't going to do anything unless you re-adjust the timing.

Ibrahim5

There isn't just the timing belt of course. Lots of other components need to be removed and re-assembled. Garages love to damage other things whilst they are repairing something else. They also like to throw loads of the parts in the bin at the end because they can't be bothered to put them back or they can't remember where they were from.

jgradisher

Ibrahim5 said:

I like the bit about trying one belt and then another one. You can only muck the timing up. I would always use the best belt possible but if the belt is turning it's obvious that you've messed the timing up. Changing the belt isn't going to do anything unless you re-adjust the timing.

Thanks for that. I'm beginning to think the sticky actuator may be a red herring, because if it was the turbo, then the check engine light should have come on at some point, and they did not mention that at all.

Goudy

There's little relation between the timing belt and turbo actuator. (though I suspect it's the vanes that are stuck due to soot/carbon and the actuator itself just can't over come that).

Yes an engine out of timing may produce more soot (which will bake to hard carbon) and that could speed up the process of jamming up the turbo actuator/vanes but I would suspect you'd notice that if it was driven like that for so long.
The same thing can be said of an intermittent sticking actuator. 
Every time it sticks, it's fuel to air ratio gets screwed up and it'll produce more soot, adding to the problem of carbon build up.

If the turbo is worn, oil will leak internally and externally, adding to the carbon build up, so a new or rebuilt turbo is needed.

If it's not worn out and leaking, you might get away with manually working the actuator arm.
It's hard to get too but I seem to remember you can get at it via the front left wheel arch and remove the heat shield.
Then hook a bent wire coat hanger on the arm to work it back and forth to free is off (for a while at least).
It takes some effort though.

I have to add, the turbo is a very common issue with the TDV6 and it very well known it will give grief as some point.
You don't state the vehicles mileage but I suspect it's at the age/mileage where the turbo is clapped out.

As for blanking off the EGR, well that generally helps prevent oily gunk in the intake side, but the exhaust/turbo side tends to run a little hotter and it's just not designed for that.

The recycled exhaust from the EGR cools combustion, without it low fuel combustion cycles will scream mad hot as it's pumping only air and not airless exhaust gasses.
Excess heat in the exhaust/turbo doesn't bode well for the turbo, it'll turn the soot in to hard carbon quicker and likely damage the turbo bearings and seals.

I seem to remember the trick with these TDV6's was to restrict the EGR flow rather than blank the EGR completely off.

jgradisher

Goudy said:

There's little relation between the timing belt and turbo actuator. (though I suspect it's the vanes that are stuck due to soot/carbon and the actuator itself just can't over come that).

Yes an engine out of timing may produce more soot (which will bake to hard carbon) and that could speed up the process of jamming up the turbo actuator/vanes but I would suspect you'd notice that if it was driven like that for so long.
The same thing can be said of an intermittent sticking actuator. 
Every time it sticks, it's fuel to air ratio gets screwed up and it'll produce more soot, adding to the problem of carbon build up.

If the turbo is worn, oil will leak internally and externally, adding to the carbon build up, so a new or rebuilt turbo is needed.

If it's not worn out and leaking, you might get away with manually working the actuator arm.
It's hard to get too but I seem to remember you can get at it via the front left wheel arch and remove the heat shield.
Then hook a bent wire coat hanger on the arm to work it back and forth to free is off (for a while at least).
It takes some effort though.

I have to add, the turbo is a very common issue with the TDV6 and it very well known it will give grief as some point.
You don't state the vehicles mileage but I suspect it's at the age/mileage where the turbo is clapped out.

As for blanking off the EGR, well that generally helps prevent oily gunk in the intake side, but the exhaust/turbo side tends to run a little hotter and it's just not designed for that.

The recycled exhaust from the EGR cools combustion, without it low fuel combustion cycles will scream mad hot as it's pumping only air and not airless exhaust gasses.
Excess heat in the exhaust/turbo doesn't bode well for the turbo, it'll turn the soot in to hard carbon quicker and likely damage the turbo bearings and seals.

I seem to remember the trick with these TDV6's was to restrict the EGR flow rather than blank the EGR completely off.

Thanks. For what it's worth, the car has 140k miles on it, 55 reg. I've been using supreme diesel and giving it STP treatments pretty much since I acquired it 14 years ago. I tend to 'blow off the carbon'  whenever I get the chance. And I once had an indie tell me it was one of the cleanest engines he's ever seen.

Haven't had any smoke of note, except when blowing off the carbon on the highway.

Anyway, thanks for your observations and suggestions.

Goudy

You won't blow off soot/carbon by accelerating hard or flooring the throttle at high speed, quite the opposite. 

All you are doing is creating more soot/carbon. You are working the engine harder so it uses more fuel, so creates more soot/carbon.

The soot/carbon is just a by-product of combusting fuel with air.

The more fuel you burn the more by-product you get, that's why it smokes when you are working the engine heavily "blowing off", it's just lots of burnt fuel you are seeing.

It will produce less soot/carbon on a steady light throttle once the engine is up to temp, as that's when it's using less fuel.

Over the years/miles all this soot builds up on the turbo and bakes hard as the turbo gets very very hot.
Eventually it's so crusty with the stuff the vanes/wastegate no longer operate smoothly and the actuator, either a vacuum system or a small electric motor, can't overcome the sticking vanes/wastegate as they don't produce a lot of force.

Turbos with motor driven actuators will often damage the actuator motors as they just end up getting hot and burning out trying to push/pull against stuck vanes/wastegates.

If they are easy to get at a simple trick is to hand operate the wastegate/vane arm (not the actuator).
If it's stuck you will often need a lever like a long screwdriver to force the arm back and forth.
With enough force you can break the carbon up that causes them to stick for a while. I say for a while as you continue to run the car, it burns fuel and creates more soot so will eventually suffer again.

If the turbo isn't all leaky, it might be worth trying to free it off but I would say at 140k you're looking at a pretty worn turbo (or two) so would advise to find a local turbo specialist.

jgradisher

Final follow-up. Indie had a look and is replacing the turbo.

It was not a stuck actuator. It appears some foreign object has got into the turbo and damaged the vanes.

Indie is 99% convinced it was caused by something falling in when the cam belt was changed. Getting a full report tomorrow.

jgradisher

Thanks for the comments and the advice.