Polo 9N AWY 'check engine' light on

[Akagi]

When is the next thread?

Today...

I will be getting my mechanic to have a look, but obviously it is Sunday tomorrow, so this is more of an "in the mean time, what can I try" thread.

My car is a 2002 VW Polo 9N 1.2 6V AWY with 138K on the clock.

I was driving home earlier today and the 'check engine' light came on.

There are no strange sounds coming from the engine, the engine idles smoothly, the engine pulls fine through all gears, there is no "lumpiness" and no misfires throughout the entire rev range. I have checked all fluids and all seem fine, I have checked all hoses and plugs as much as I could at the side of the road (just visual checks for obvious splits or loose hoses/disconnected plugs etc) and there don't appear to be any obvious issues.

I have tried various methods which are supposed to clear lights/errors or reset the ECU (I don't know how many [if any] of these are genuine methods but I tried these regardless):

- Pressing in trip button for 2 seconds and turning to the right
- Pressing in trip button for 2 seconds with key turned to lights position, and turning to the right
- Pressing in trip button, holding, turning ignition to lights position, holding, turning ignition off, removing keys, and releasing button
- Disconnecting negative terminal for 15 minutes and re-connecting, then starting engine
- Disconnecting negative terminal for 3 minutes, then re-connecting, then turning ignition to lights position, waiting 3 minutes, turning ignition off, removing key, putting key back in, then starting engine

Points to note:

- Engine had a full tank of petrol when this happened, it was cheap supermarket petrol though (Tesco 95) and I usually use Momentum/Ultimate/Super or sometimes Esso 95
- Radiator fan is faulty and non-working (blows fuses) but it has been like this for 2 weeks/500 miles, I have been careful with the engine, and never seen it go above 90 degrees. (replacement fan is in the post)
- The car was involved in an accident a few weeks ago, but it has been fine from after the repairs up until now (again, 2 weeks/500 miles) and it was fine before (never had the light come on)

The only engine component which needed replacing following this incident was the radiator.

If anyone could shed any light on the subject or give me things to try, it would be much appreciated!

I do not have access to any diagnostic equipment.

Finally, would you advise against driving the car while the check engine light is on persistently, even if there are no obvious issues?

Kind regards!

 

[[TW]Fox]

You normally use Momentum 99 in a 1.2 6v?

 

[Kenai]

Get the codes read and go from there, it could be literally anything.

Probably just a failing sensor of some sort if it otherwise seems fine.

 

[rodenal]

As above, pull the codes - playing the guessing game is pointless without at least a hint

 

[bledd]

You normally use Momentum 99 in a 1.2 6v?

This... lol

The most common cause I've seen for a CEL is failed oxygen sensor. Get the code read before throwing parts at it.

Oxygen sensors (or lambda sensors) tend to give up after 10 years or so. Typically a £50 part plus fitting

 

[miniyazz]

Get a £5 ELM adapter from eBay and Torque.

 

[MagicBoy]

As above, pull the codes - playing the guessing game is pointless without at least a hint

This.

I've had CELs on my VAG cars for a bad MAF, coolant temp sensors and something else I can't remember and it drove OK. Oddly a bad crank position sensor didn't trigger it on the Bora.

 

[Dale V]

try a hammer

 

[leigh_boy]

if u want to come to eastbourne il read the codes for you

 

[commited]

Get a £5 ELM adapter from eBay and Torque.

This.

 

[Dis86]

Jesus...is this another ACME car falling to bits thread?!

 

[Vita]

Get the codes and go from there.

 

[~Divine~Wind~]

ELM and Torque as above mate.
I wouldnt even be wasting money taking to a garage until I had checked the codes myself.

Could be a failed sensor, could be a destroyed engine

 

[Akagi]

Yes I normally put Momentum in a 1.2 6V because at something like £2 more per tank, it seems pointless not to. Tesco is the only local petrol station which is open 24hrs, and if the choice is Momentum at 127p or Tesco 95 at 124p, I'll use Momentum. The pump had no Momentum this time though.

Yes it is another Acme car falling to bits thread...

I'll get the codes read, was just hoping someone would know something obvious to check which I've missed.

I've been advised (without checking codes yet, I'll get on that right away) that it is most probably a faulty sensor, and it could even be something as simple as a "bad" bit of fuel being dragged through the system.

The guys over on Pistonheads and ClubPolo have basically said that it should be fine to drive until the codes are read if there are no obvious issues.

 

[~Divine~Wind~]

Coming soon in Acmes next thread.... Misfire led to Engine going boom

Seriously hope its just something simple tho mate

 

[Akagi]

Lets hope that doesn't happen... I mean, it definitely isn't misfiring.

I hope it is something simple too... I know you are probably all fed up with the Polo threads, but I'm fed up with owning this damn car at this point... All I wanted to do was fix it and run it until the new year when I can wave bye bye to it. Apparently that is too much to ask even after replacing almost EVERYTHING.

Seriously, I need to get this thing re-registered. Not much of it is 12 years old anymore.

 

[lemonade]

Does that car really have only 6 valves? Was it made in the 50's or something?

 

[MagicBoy]

It's a 3-cylinder engine.

54hp has 6 valves, the 64hp has 12 valves.

 

[rodenal]

Yes I normally put Momentum in a 1.2 6V because at something like £2 more per tank, it seems pointless not to. Tesco is the only local petrol station which is open 24hrs, and if the choice is Momentum at 127p or Tesco 95 at 124p, I'll use Momentum. The pump had no Momentum this time though.

Well no, it's pointless to do it as it's a 1.2 with about 5bhp regardless of whether it's £0.02 or £20 more a tank

If there's nothing obviously wrong with the way it drives I wouldn't be overly worried about using it

 

[Akagi]

Think I may have found what the issue is, the cable for the lambda sensor looks like it got pinched in the accident and the insulation is torn and ragged and there is bare wire showing, so I guess it might have shorted on something.