2011 on. So last of the 169 models and then the new one.
Technical 2013 Panda 1.2 rough idle and failing emissions test.
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Technical 2013 Panda 1.2 rough idle and failing emissions test.
2012+ section.. so should be VVT 
Hi Jock,
On this one the lambda test result of over 1.4 is the MOT emission test equipment calculation , not a voltage reading from the o2sensor of the car.
The car looks like it may be running ok as the co and hc readings are low and a pass on the MOT emmision test.
Normally a high mot lambda reading is due to leaks in the exhaust system allowing oxygen to enter the exhaust flow before the tailpipe sensor of the MOT test device .
I have never seen such a high mot lambda reading as 1.4.
Cheers
Jack
plasmahal2020
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The second test was a higher value!!!!!
Nope, it's all stock.
I did check the injectors this morning and while all have a little rotational movement, all the plugs seem fine.
There is an slightly different noise once warmed up and the exhaust noise also sometimes sounds like it mis-firing even though the reader says no mis-fires.
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plasmahal2020
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So what can i check for now?
Leaks around the CAT? I know the CAT has 2 sensors on it one pre and one post.
A visual/audible inspection of the exhaust or is there anywhere else i need to look at?
Thanks.
Leaks around the CAT? I know the CAT has 2 sensors on it one pre and one post.
A visual/audible inspection of the exhaust or is there anywhere else i need to look at?
Thanks.
Where are you based?
Is the exhaust back box the typical 'peeling onion'.. shedding layers.. or is it a factory replacement??
Charlie
Is the exhaust back box the typical 'peeling onion'.. shedding layers.. or is it a factory replacement??
Charlie
Thanks Jack. I'm still getting my head round all this diagnostics stuff. Making progress I think but also a lot to learn still. So every little bit helps!
Plug or partially plug the tail pipe with a damp rag ,any exhaust leaks will be very greatly pronounced , don't rev the engine while doing this.
If the engine can keep running with the tail pipe plugged the exhaust has a big hole somewhere.
For your high mot reading any leak will be after the cat.
Does your code read show live data?
Sounds like it's drawing air somewhere, I've heard of inlet manifolds cracking giving rise to weak mixture, perhaps one reason it's OK when cold, a good spray with WD-40 may help locate the issue if it suddenly clears. Or what about the carbon filter canister?
plasmahal2020
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Ok most live readings expired.
Try the damp rag in tail pipe to find exhaust holes.
Also perhaps remove the Lambda sensors and give them a decent clean - or indeed replace them as they're not expensive and don't last forever necessarily. Remember that a sensor that 'thinks' it's seeing higher than normal O2 levels will give similar output voltage as one that IS seeing too much O2. So a faulty sensor could cause the same issue and I have had this on another car myself so I know they do need cleaning/replacing sometimes.
Whilst you're under the car, locate the Crank Position Sensor (next to the crank pulley, at the front of the block, on the drivers side of the engine), remove it, clean it up (and the timing marks on the crank pulley itself ) and replace. Cannot hurt.
Have you also tried a proper Italian tune-up to blow out all the cobwebs and maybe even reveal the root cause of the problems under really high load?
Whilst you're under the car, locate the Crank Position Sensor (next to the crank pulley, at the front of the block, on the drivers side of the engine), remove it, clean it up (and the timing marks on the crank pulley itself ) and replace. Cannot hurt.
Have you also tried a proper Italian tune-up to blow out all the cobwebs and maybe even reveal the root cause of the problems under really high load?
plasmahal2020
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Ok, I have a new oxy/lambda sensor and i tried in both the top and bottom positions either side of the CAT. This made no difference.
I also tried the damp rag up the exhaust trick and there is air blowing a little out of the back box on the front side.
As the car warmed up, there was dirty water coming of the front seam.
I carefully put my hand around the back box but could not feel anything but there is a definite sound.
I also tried the damp rag up the exhaust trick and there is air blowing a little out of the back box on the front side.
As the car warmed up, there was dirty water coming of the front seam.
I carefully put my hand around the back box but could not feel anything but there is a definite sound.
Did the engine keep running when you blocked tail pipe?
plasmahal2020
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Yes.
That is 100% proof there is a huge hole in exhaust.
If you bought a cheap no name o2 sensor and it is still fitted take it out and put the original back.
If you bought a Bosch or ntk/ngk sensor well done leave it in.
Get the exhaust fixed / replaced get it retested and be amazed
If you get chance to see car up on ramp please take a pick of hole /s and post pic on here.
A garage with asmoke machine should be able to find any leaks within minutes
Anyone that can get the car in the air and is not totally blind should be able to find the leak in seconds !
It won't be a huge hole, as you'd hear that particularly as there is only one silencer that does any real silencing, so I suspect the hole is small. However, the exhaust pulses will allow low-pressure zones where air can be pulled in to the system from the outside, so the advice to get the exhaust fixed/changed is good. It does take quite a lot to make an engine stop by plugging the exhaust so I'm not entirely surprised that a damp rag didn't stall it completely, but it does look like it might be pointing you in the right direction.
Mot emmisions test machine reading over 1.4 not a large leak of air into exhaust?
The highest reading I have previously seen was 1.2 caused by a 25mm diameter hole and a split , both in the middle pipe.
But I guess a smaller hole in a low pressure region(hadn't considered that) could have a similar effect .
I do hope we get some pictures so we can see for ourselves
