2005 Volkswagen Polo 1.2 E (55PS) - Help with Error Codes

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Fri 27 Apr 2012 15:55
2005 Volkswagen Polo 1.2 E (55PS) - Help with Error Codes - SYPolo

I got an engine management light recently and the car seems to be lacking power sometimes and mis-fires under acceleration, usually when the engine is hot. It is sometimes hard to start the engine aswell when it is hot. Starts fine when cold.

These are the error codes I am getting (I cleared them, ran the car for a few days, and the exact codes came back two days later);

P0342

P0322

P1388

P0303.

Compression test done aswell;

Cylinder 1 - 10.5 bar

Cylinder 2 - 7.5 bar

Cylinder 3 - 7.5 bar.

Coils and spark plugs have been replaced recently, and swapped around to see if mis-fire moved and it didn't. Engine wiring has been tested too by an auto electrician. Thottle body removed and cleaned, hoses and vacuum pipes checked aswell for leaks.

Any ideas what the fault could be?

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Fri 27 Apr 2012 17:19
2005 Volkswagen Polo 1.2 E (55PS) - Help with Error Codes - unthrottled

Compression test done aswell;

Cylinder 1 - 10.5 bar

Cylinder 2 - 7.5 bar

Cylinder 3 - 7.5 bar.

Those numbers are very low. 7.5 bar=110 psi. A little higher than I would get from a healthy chainsaw engine!

First two fault codes are cam and crankshaft sensor-could explain misfire.

3rd one indicates over retard for the camshaft phaser-which would explain the low compression numbers.

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Fri 27 Apr 2012 18:18
2005 Volkswagen Polo 1.2 E (55PS) - Help with Error Codes - SYPolo

Thanks for the reply.

Which sensors do I need to replace then?

Edited by SYPolo on 27/04/2012 at 18:20

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Fri 27 Apr 2012 18:34
2005 Volkswagen Polo 1.2 E (55PS) - Help with Error Codes - unthrottled

Try either cam or crank sensor-they're cheap parts, after all. Not sure what to suggest about the retarded cam phasing though! I didn't realise that engine had VVT.

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Fri 27 Apr 2012 18:37
2005 Volkswagen Polo 1.2 E (55PS) - Help with Error Codes - SYPolo

In simple terms, what does retarded cam phasing mean?

Is it likely the fault will be cured by replacing the engine speed sensor, the camshaft sensor and the crankshaft sensor?

Cheers again :-)

Edited by SYPolo on 27/04/2012 at 18:42

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Fri 27 Apr 2012 18:43
2005 Volkswagen Polo 1.2 E (55PS) - Help with Error Codes - elekie&a/c doctor

Those compression readings are too low .You need a cylinder head overhaul(and usually a new timing chain) and a software update to the engine Ecu.Don't throw money down the drain by changing parts/sensors/coils etc.The 3 cylinder engine on these are total trouble.hth

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Fri 27 Apr 2012 18:47
2005 Volkswagen Polo 1.2 E (55PS) - Help with Error Codes - unthrottled

Whoa! If the cam is retarded, then the inlet valves will be closing late and bleeding off cylinder pressure. It might just be the phaser isn't working properly. You must come accross dodgy VVT systems, Doc.

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Fri 27 Apr 2012 18:50
2005 Volkswagen Polo 1.2 E (55PS) - Help with Error Codes - SYPolo

Is the camshaft phaser the same as the camshaft sensor?

Nothing comes up when I Google VW Polo camshaft phaser for this engine, only camshaft sensors?

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Fri 27 Apr 2012 19:06
2005 Volkswagen Polo 1.2 E (55PS) - Help with Error Codes - elekie&a/c doctor

No vvt system on these.Just a very poorly engineered simplex chain system and guides .I have seen loads of these in pieces.Poor show Volkswagon.hth

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Fri 27 Apr 2012 19:17
2005 Volkswagen Polo 1.2 E (55PS) - Help with Error Codes - unthrottled

I didn't think it had VVT. But fault code P1388 relates to retarded camshaft phasing. What gives?!

engine-codes.com/p1388.html

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Fri 27 Apr 2012 19:20
2005 Volkswagen Polo 1.2 E (55PS) - Help with Error Codes - elekie&a/c doctor

You are probably correct;retarded phasing due to worn chain.hth

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Fri 27 Apr 2012 19:45
2005 Volkswagen Polo 1.2 E (55PS) - Help with Error Codes - unthrottled

Ah!

Flippin' heck. Must be more than one tooth out with compression numbers like that!

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Fri 27 Apr 2012 20:10
2005 Volkswagen Polo 1.2 E (55PS) - Help with Error Codes - SYPolo

Thanks for all the replies guys.

So it's looking like a new timing chain and tensioner? Surely if if was the timing chain, wouldn't it be hard to start all the time, not just when hot? If the timing was out wouldn't it show on VAG-COM as a fault?

And why am I getting the other error codes? Is it possible that the jumped timing chain means the ECU is receiving different readings from the other sensors, making it think there's a fault with them? So the timing chain is having a knock-on effect basically on everything else?

The engine has done 112,000 miles from new (I am the only owner) and it hasn't had any work done before to the timing chain or tensioner.

Edited by SYPolo on 27/04/2012 at 20:21

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Fri 27 Apr 2012 21:14
2005 Volkswagen Polo 1.2 E (55PS) - Help with Error Codes - unthrottled

Quite possibly. If the timing chain has jumped then the figures the ECU is getting from correctly functioning cam and crank sensors might be 'implausible'. OTOH, dodgy sensors can sometimes faiul when hot, but work ok when cold.

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Fri 27 Apr 2012 21:50
2005 Volkswagen Polo 1.2 E (55PS) - Help with Error Codes - SYPolo

The mechanic I use is coming to check the timing on Tuesday.

Thanks for all the help. Was just after a heads up really on the possible problems!

In your opinion, from the symptoms described, does it seem like the timing chain is the likely problem?

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Fri 27 Apr 2012 22:31
2005 Volkswagen Polo 1.2 E (55PS) - Help with Error Codes - unthrottled

It seems to be the most likely problem. Those compression numbers are too low. I'd be looking for least 12 bar on a healthy modern n/a petrol engine.

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