Polo 9N AWY 'check engine' light on
- Thread starter Akagi
- Start date
There are other things he will need to look at as well, I'll get a list later. 
Soldato
I'm sure you must be spending more on repairs and fixes then you would on a lease. 
Right so, the OBD reader returned three fault codes:
16804
17978
16556
The first one, 16804 isn't in the accompanying booklet, but Google suggests that it is "Catalyst System; Bank 1: Efficiency Below Threshold"
The second one, 17978 isn't in the accompanying booklet, but Google suggests that it is "Engine Start Blocked By Immobiliser"
The third one, 16556 is in the accompanying booklet, and it is "Fuel Trim: System Too Rich: Bank 1"
I am not concerned about the second one regarding the immobiliser, as the engine starts and runs fine, there have been no issues with the immobiliser, and I think it may have happened when I had a third party key programmed for the car.
So looking at the first and third ones then:
16804 - Catalyst System; Bank 1: Efficiency Below Threshold
16556 - Fuel Trim: System Too Rich: Bank 1
Any ideas? I'm guessing that 16804 is that lambda sensor, or could it be the cat? Is 16556 likely to be related and/or possibly the cause of 16804?
Should I clear them and see if they come back, first off?
16804
17978
16556
The first one, 16804 isn't in the accompanying booklet, but Google suggests that it is "Catalyst System; Bank 1: Efficiency Below Threshold"
The second one, 17978 isn't in the accompanying booklet, but Google suggests that it is "Engine Start Blocked By Immobiliser"
The third one, 16556 is in the accompanying booklet, and it is "Fuel Trim: System Too Rich: Bank 1"
I am not concerned about the second one regarding the immobiliser, as the engine starts and runs fine, there have been no issues with the immobiliser, and I think it may have happened when I had a third party key programmed for the car.
So looking at the first and third ones then:
16804 - Catalyst System; Bank 1: Efficiency Below Threshold
16556 - Fuel Trim: System Too Rich: Bank 1
Any ideas? I'm guessing that 16804 is that lambda sensor, or could it be the cat? Is 16556 likely to be related and/or possibly the cause of 16804?
Should I clear them and see if they come back, first off?
Soldato
I'm sure you must be spending more on repairs and fixes then you would on a lease.
I'm going to save this thread and come back to it every time I feel bad about spending so much money on running my cars - it'll make me feel so much better
Soldato
Both sound like lambda sensor
Its not so bad now I have the confidence to attempt to sort lots of things myself. I'm happy to have a crack at anything that doesn't involve taking the engine apart.
And old VW parts are very cheap, especially if you get them from breakers.
And old VW parts are very cheap, especially if you get them from breakers.
SNAP
We didn't worry about that one either.
Ours also has a new lambda sensor already fitted with similar codes still logged.
All have cleared..
Right then, Does your code reader do live data?
If so, reset the codes, reset the "emission related data" or whatever your code reader calls it and then look at LIVE DATA..
Pull up info on Bank 1 cylinder 1 and have a look at the reading. If it's a flat line 0.3v or there abouts the lambda sensor is goosed..
But wait for a good few mins while watching it to allow the car to warm up and try to go into closed loop (closed loop = ECU takes note of what lambda says and adjusts fuel trim accordingly)
If lambda sensor is giving a false reading (usually a static figure) then the fuel trim will increase incrementally until it gets to a point where it decides it's either too rich (or too lean) to be a real signal and then flag up the error with the corresponding "System too rich" code and CEL.
Watch this for how to's
Edit** Wrong video
OK Correct one in there now
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I don't believe it has a live readout no. I have taken the advice from the VW forums for now, which was to clear the codes and keep driving the car and see if it comes back. If there is a persistent issue, it will.
I have also wound up the damaged lambda sensor wire with insulation tape and cable tied it so it doesn't flap about.
Drove 25 miles including a bit of an Italian tune up, and cycled the ignition several times, no light or fault codes back yet.
Fingers crossed.
I have also wound up the damaged lambda sensor wire with insulation tape and cable tied it so it doesn't flap about.
Drove 25 miles including a bit of an Italian tune up, and cycled the ignition several times, no light or fault codes back yet.
Fingers crossed.
150 miles in now and no issues
Looks like it might have just been gremlins.
Looks like it might have just been gremlins.
Probably the wire on the lambda you repaired!
All the suspension is off ours now, top mounts are binding (someone's fitted coilovers.... badly)
The fun never stops.
Still no further forward on the orange oil light though.
Not quite so much of a rush now though as the lad who was getting the car, failed his hazard perception test today. DERP.
Boss has disowned him
All the suspension is off ours now, top mounts are binding (someone's fitted coilovers.... badly)
The fun never stops.
Still no further forward on the orange oil light though.
Not quite so much of a rush now though as the lad who was getting the car, failed his hazard perception test today. DERP.
Boss has disowned him
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You'll want to replace the front suspension bushes while you're at it if you haven't already.
And what brand of coilovers are they?
And what brand of coilovers are they?
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150 miles in now and no issues
Looks like it might have just been gremlins.
I think my post cat lambda is dead but I get a sort of rolling CEL rotation, a few weeks on, a few weeks off, a few weeks on, a few weeks off. Been doing it bloody ages
150 miles isn't necessarily enough to make it come back on, it might reappear in 10 or 1000 or 2000...
Associate
My 12 year old clio has had it's EML on for a good 6 months now. It turns itself on/off when it feels like it.
Lambda sensor
Lambda sensor
Front lower arm rear bushes have already been done acme.
We're not sure whether it's supposed to have central locking or not (without dismantling the door card to find out)
If it does..... It doesn't work.
Sheesh.
£400 quid sheds hey, don't you love em! (53 plate car)
We're not sure whether it's supposed to have central locking or not (without dismantling the door card to find out)
If it does..... It doesn't work.
Sheesh.
£400 quid sheds hey, don't you love em! (53 plate car)
If there is a key hole in each door and no LED next to the door lock pegs, it isn't meant to have central locking. If there is only a key hole in the drivers door and there are LED's, then it is meant to have it.
Central locking cars will also have remote keys with the buttons and the flip-out key blade, non central locking cars have a regular key.
Central locking cars will also have remote keys with the buttons and the flip-out key blade, non central locking cars have a regular key.
Got a bit worried last night cos the car wouldn't start, but it turned out to be a cable which had broken off of the starter motor
One less thing to fix then, it doesn't have CL
Found out what was wrong with the top mounts / coilovers on Saturday...
Some blind idiot fitted the spring perch upside down so it not only ground itself into the rubber top mount but totally missed the top mount bearing.
That explains the spring twanging on lock to lock then.
No idea what make they are Acme.
Found out what was wrong with the top mounts / coilovers on Saturday...
Some blind idiot fitted the spring perch upside down so it not only ground itself into the rubber top mount but totally missed the top mount bearing.
That explains the spring twanging on lock to lock then.
No idea what make they are Acme.
Not having CL is a right pain at times. Especially when you have passengers and have to explain to them how to lock things. Then you give up and walk round the car doing it yourself. I've come back to the car several times and found the passenger door or boot unlocked because someone forgot (possibly me). Or I'll say to them when we're away from the car "did you lack your door?" And usually get either "Oh no I forgot!" Or "I have to lock it myself?! How old is your car?" Cue me running back to the car. You have to unlock the boot from outside with a key as well, so to get something out of the boot quickly you have to turn the engine off and have your music stop and so on. Very wearing. As is not having a boot light once you get there.
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