vauxhall astra design twinport mk v(5) 2005 1.6 MOT FAIL

14 Feb 2013
Reaction score
United Kingdom

I am having problems with my car these are symptoms -
vauxhall astra design twinport mk v(5) 2005 1.6 has done 70K miles

Failed on MOT all emissions (See link)
- Running very lean
- ECU putting tons of fuel in because of lean running so its eating tons of fuel
- White intermittent smoke from exhaust only seen myself once

Garage number one says (After MOT fail on emissions) -

The o2 sensor gone and needs a new CAT. (£550)

Garage number two says (After emissions fail and white smoke)

- Needs new engine (Piston rings gone) (£1500)

What I have done

- New sparks
- New air-filter
- Various chemical cleans (RedX, Injector Cleaner, Cataclean)
- Only one error code now cleared and not returned (Running lean)
-Linked to laptop no obvious problems

Possible problem
- the o2 sensor might not be functioning correctly seems to take some times a few seconds to cycle further testing will be done on weekend although this does not explain white smoke.

Points to note

- Car idle perfect
- Car drives fine
- Using lots of fuel
-No signs of blow headgasket

When the car was running I put my hand under exaust fumes and it was so hot it burnt
when the car was blowing white smoke I put my hand in same place and it was just warm air, I could also feel flicks of liquid got a white piece of paper and the liquid was clear like water.

Any suggestions as to what could be causing white smoke.

Originally thought maybe the cat is dead but this would not cause smoke.
Then thought maybe its unburned fuel but this would be black smoke.
Sponsored Links
In a nutshell.....white smoke = water vapour, blue smoke = burning oil, grey / black smoke = excess fuel.
An emissions fail can't really be argued with, although the garage should give the car every chance i.e adding a fuel additive and getting the catalytic converter seriously hot.
As for a goosed engine, well a compression check would be a good start.
Whats your actual MPG?
John :)
The results you have point to either incomplete combustion or a goosed cat.

Generally white smoke means water as John has said but it could be caused by high concentrations of un-burned fuel. I assume you are not loosing any coolant? Does the exhaust smell of petrol?

If the O2 sensor is not working properly this could be causing the over fueling. However, if this has been happening for any length of time it could have killed the CAT.

Are you loosing any oil? I doubt the piston rings have gone at 70K miles and you would be more likely to see blue smoke and would notice a loss of power.
Over fueling might suggest a faulty engine coolant temp sensor? The one the ECU looks at to knock the choke off, usually a two wire type.
Sponsored Links
New update -

I have some picture to follow.

While the car was idleing about an hour on and off. I noticed a large puddle on the floor by exhaust after smelling it, it just seems to be water but as I understand it no fluid should be coming from exhaust. This was accompanied by small amount of white smoke. 

Checked the coolant and doesn't seem to be going down going to buy a test kit from eBay to check the gasket.

idle only results
I would watch the ECT readings from a cold start, hard to say but yours looks high at 111 degrees celcius but it all depends on how hot the engine was.
As suggested the ECT is a cheap place to start as it controls the fuelling and its a very common failure.
lambda sensors on live data should switch between roughly 0.2 to 0.8 volts once per second, 0.2 being lean and 0.8 rich. A perfect mixture the sensor should read roughly 0.5. Before cat sensor should switch as above and after cat should be around 0.5 if all is well with the mixture and cat.
Yea that's what I thought, apparently its normal for my car its the reason they removed the temp from dash.
Sponsored Links