Very rough idle and emission light on 2.0 FSI

[cunni319]

Hi the other day my 03' 2.0 FSI A4 starting quite violently shaking when i was parked idling, it only does it under 1000 rpm soon as i press the accelerator the vibration stops, just quite worrying when i stop at lights etc,etc. Also the day after waht i thought was the engine management light came on, however after consulting the handbook realised its the exhaust/emissions light. Havent had time to take it to the garage yet and done about 600 miles since i noticed it with no ill effects....

Anyone got any ideas as to what could be causing either of the problems? Id like to think theyre linked?

Thanks in advance for any suggestions.

 

[hades-]

id go for coilpack's
but it realy needs pluging in to get the fault codes.

 

[chrisa4quat]

Is it a misfire?

 

[cunni319]

Not sure, its only when the engine is warm and sitting at 800 revs,just feels like the engines rocking almost? As soon as i touch the accelerator or whilst driving its completely fine?

 

[hades-]

as above you need a scan for codes
but i do think its a mis from the coilpacks.

 

[chrisa4quat]

Could be an air leak. Misfire should be present all the time

 

[B6Steve]

Lift the cover off the top of the engine and check the oil breather hoses, very comon to have a split there where it plugs into the rocker cover where the pipe dissappears into the inlet manifold.

 

[Paul Waterfall]

Hi the other day my 03' 2.0 FSI A4 starting quite violently shaking when i was parked idling, it only does it under 1000 rpm soon as i press the accelerator the vibration stops, just quite worrying when i stop at lights etc,etc. Also the day after waht i thought was the engine management light came on, however after consulting the handbook realised its the exhaust/emissions light. Havent had time to take it to the garage yet and done about 600 miles since i noticed it with no ill effects....

Anyone got any ideas as to what could be causing either of the problems? Id like to think theyre linked?

Thanks in advance for any suggestions.

Hi, did you manage to sort the rough idle problem out.

Only mine sound the same as yours, I`ve replaced the chain and tensioner and cam / crank sensors, also the timing is spot with the marks.

Thanks Paul.

 

[Ovid]

Have you scanned yours Paul?

 

[Paul Waterfall]

Used VCDS Lite, P1340 cam / crank corrolation fault . New cam and crank sensors, new cam chain and tensioner. I used rod in cylinder 1 to check tdc and the crank was spot on, had to remove cambelt of camshaft to correct the timing mark, released the belt tensioner and turned the crank to check timing and did this 3 times, each time I reset the timing mark it slipped back but got right on the 3rd attempt and got it spot on. Started the car and still got a rough idle. I've rechecked the timing marks and still spot on.

 

[Ovid]

Are you sure the cam chain timing is correct its usually that which causes this fault and is oil pressure correct as oil scrounger getting blocked can cause it although all the ones ive done its cams and chain which are out.Check ign advance in vcds mvb and see if timing is stable or bouncing from 0 to 28 degrees.

 

[Paul Waterfall]

Hi Ovid, on VCDS the timing is all over the place. When setting TDC with rod in pot no 1, would it be when the rod peaks on its way up as there is some crank rotation b4 the rod starts to fall back down. If this is the case I'll reset the timing and check the cam lobes on pot no 4 are pointing to each other equally. As it is the timing marks are spot on with the covers.

Thanks Paul

 

[Ovid]

its cam chain timing thats out , its a bitch to get right i put a thread up somewhere on here