Xantia 2.0i 16v idle problems

VertVega · Post by **VertVega** » 14 Dec 2010, 13:24

merlin617 wrote:... was close to dying on the A3 @ 50mph in 5th gear....

In my opinion your case is not idle motor related. As the name suggests you feel the symptoms while idling.
If there was also lack of power and/or engine hesitation then it could be MAP sensor.
This was just one option and there can be other causes as well.

merlin617 · Post by **merlin617** » 14 Dec 2010, 13:59

VertVega wrote: If there was also lack of power and/or engine hesitation then it could be MAP sensor.
This was just one option and there can be other causes as well.

would a MAP sensor failure be clearly indicated by the Lexia diag ?

Thanks for your replies so far chaps

VertVega · Post by **VertVega** » 14 Dec 2010, 14:42

MAP sensor error might cause an instantaneous engine K-light and then an OBD error code will be registered to ECU.
i.e this code can be read by Lexia.
The K-light does not necessarily be seen all the time on the dashboard.
With Lexia you see all possible errors recorded.

Did the engine almost dying happened when you pressed the clutch pedal to change gears?
If yes then one more reason to suspect the MAP.

Edit: If you write more about the symptoms, conditions and etc. I guess you will have more chance to get replies/suggestions.
Don't buy a new MAP sensor yet

merlin617 · Post by **merlin617** » 14 Dec 2010, 16:27

Started up cold this morning running slightly rough as it warmed up there was noticeable missing in the engine and lack of power/spurts of energy. On the A3 there was a lot of vibration trying to accelerate from 40mph.

I turned back to London and it struggle to move from rest all the way back which was mostly 30mph or less. As long as I kept my foot gently on the throttle it managed to get me home.

I half wondered if the timing belt had slip a tooth. Timing belt was changed at 63,000, car has now done 81,000.

VertVega · Post by **VertVega** » 14 Dec 2010, 16:57

Based on your recent post, I would say that these symptoms are
- defintely not caused by idle stepper motor
- not likely caused by MAP sensor
but they might be because of
- lambda sensor (lack of power, poor fuel economy, hesitation during accelaration)
- spark plugs (misfiring, lack of power, poor fuel economy)

Try to check spark plugs and replace if they look in bad condition.
This option is much cheaper than lambda sensor (also called Oxygen sensor).

Lets wait and hear what other members think about this case.
Did you notice any big increase in your fuel consumption? (Some increase is normal due to the cold weather.)

Sid_the_Squid · Post by **Sid_the_Squid** » 14 Dec 2010, 20:53

Running on 3 cylinders?
Could be the plastic ignition coil/spark plug cover has come loose, Its only held on by those small Allen blots, on my 1.8 it worked loose one day car would start and run on 3 cylinders but very roughly.

merlin617 · Post by **merlin617** » 30 Dec 2010, 13:28

Just want to give you a heads up, it turned out to be a duff spark plug. Its still wanting in acceleration and I am getting 22 MPG !

How long do Lamda / MAP sensors last can they half fail ? can you test them off the car?

car has done 81k

Thanks all

VertVega · Post by **VertVega** » 30 Dec 2010, 14:38

It's nice to hear that the problem is solved

and also very nice that you've told us the solution

- Bosch Lambda sensor is max. 160k km for heated 4 wired models (data from Bosch).
My original lambda sensor lasted for an unbelievable ~ 250k km

Good Quality!.

- MAP sensor life span was shorter, something around 180k km I had to change it.

***
Edit:

merlin617 wrote:... can they half fail ? can you test them off the car? ...

They can half fail.
They both can raise an error code in ECU. It can be read/erased, for example by Lexia.

We have same engine and this type of lambda sensor is in 2.0i 16V Xantias.
From Bosch web pages:

addo · Post by **addo** » 30 Dec 2010, 19:49

The best way to evaluate a lambada sensor is to watch the voltage steps with a "known good" unit.

If the original behaves similarly, it's fine. Mine is good, and it's at 180K (kilometres).

Post by **myglaren** » 30 Dec 2010, 23:07

I hope that was one of your deliberate mistakes/spoonerisms Adam

addo · Post by **addo** » 31 Dec 2010, 04:32

There are idle problems, and idol problems! She could leave her latex slippers under my bed.

Got to love that rubber dressing (the shiny stuff in a bottle, I mean).

Xantidote · Post by **Xantidote** » 31 Dec 2010, 11:01

Keep up the spoonerisms Addo - see what other piccies the Admin team are keeping from us!!

Xaccers · Post by **Xaccers** » 31 Dec 2010, 11:17

Xantidote wrote:

Keep up the spoonerisms Addo - see what other piccies the Admin team are keeping from us!!

Should we be worried that Steve found that photo so quickly?

Xantidote · Post by **Xantidote** » 31 Dec 2010, 11:23

No, I just say keep them coming