6n2 1.4 16v Running VERY Rough

kimidub606 · Post by **kimidub606** » Mon Jan 21, 2013 9:08 pm

Evening all hope all is well, I've recently bought a 6n2 1.4 16v x Reg 91,000 on the clock and here is my problem.

On start the car the engine seems to run very rough on the verge of misfiring its coughing and spluttering and just doesn't sound right, but for the first 20 seconds or so the engine runs much smoother. Now iv had seen alot of threads about rough idle, misfiring issue etc but it doesn't nail to one issue. Now I've had the throttle body off, cleaned up and its like brand new, HT leads are in good condition looks like they have been replaced at some point recently, same with the spark plugs, its had a new oil and filter, the air filter could be replaced but iv had it running without it and it makes no difference at all. I've had a look at all the fuses and their all right and non blown, I've heard about faults on the ECU and disconnecting the battery for 10 mins reset its things like that and this had no difference at all.

Now A friend of mine who is a mechanic is coming down this Saturday with his code reader to plug in and hopefully find the issue, but Iv got a feeling it could be cambelt issue or worse and thought please feel free to let me know.

Post by **alexperkins** » Tue Jan 22, 2013 10:29 am

If you haven't replaced the fuel filter, Id replace it

Theres a couple of things it could be

The crankshaft speed sensor - these can cause alot of running problems
A blocked crankcase breather
Camshaft idler faulty
Timing out a notch
Faulty DIS module causing a misfire

When did it last have a cambelt, idlers and waterpump change?

It could also be a worn camshaft/tappet set. The 16V engines are prone to this, and get louder with age. Its a very tap tap tap sound when the engine is running.

Plugging it into a code reader may not help you - you may need a full blown scan with VAG-COM/VCDS to help diagnose the fault.

Keep us posted on whats happening

kimidub606 · Post by **kimidub606** » Tue Jan 22, 2013 11:13 am

Yeah I will see what happens this weekend with this code reader, it maybe a top of the range or dirt cheap haven't a clue, I wouldn't say its a tap tap noise from the engine, iv dealt with noise tappets before. I took the crank breather pipe off and gave it a clean when i had the airbox off. Im not sure of when it had waterpump, idles, or crank sensor changed, haven't got alot of history with this car but I will research into these suggestions tonight and see what comes up.

Thanks for the response will keep you updated.

MJS_93 · Post by **MJS_93** » Tue Jan 22, 2013 11:33 am

I've got a 1.4 16v and mine is quite noisy but seems to be running fine. I've heard this is normal and like Alex said it can get louder with age.

benmkiv · Post by **benmkiv** » Tue Jan 22, 2013 12:48 pm

This sounds very similar to my friends 1.4 16v Lupo. Same terrible engine.

he had the cam belt done it slipped a tooth, wrecked the cam shaft positioning sensor blew a hole in the crank cover. He sold it for £1600 ahaha

But seriously i'd go easy because this sounds very much like it could be. Belt issue.

kimidub606 · Post by **kimidub606** » Tue Jan 22, 2013 5:57 pm

Yeah just taking it easy at the moment I wouldn't drive it but with work etc I need to. Spoke to the mechanic at lunch today and he suggested that it could be the EGR Valve sticking causing it just to run off the hot air from the exhaust, but Im not a 100% sure about that as when I had the airbox off when I was cleaning the throttle body, I started it up and it made little difference. Im going down the lines of timing, cambelt route.

Mite be down to see him tonight will keep you guys up to date.

Post by **alexperkins** » Wed Jan 23, 2013 9:21 am

I would be very surprised if the EGR valve was sticking - thats easy to check as you just remove its plug and see what happens.

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