PD140 engine skaing/misfiring

[rickyquicky]

Hi guys, i'm new to the forum and was recommended by 'devonmikeyboy' over here from audisportnet for some technical expertise!

Basically I have an A3 TDI PD140 DSG that has been running like crap for the last 2 months.

When the engine is under load there the engine is shaking and i've got a definate loss of power.

Had the car hooked up to a diagnostics machine that showed a misfire on cylinder 3, changed the loom and injector and the car seems to be running a little better but it is still shaking under load, and more rarely at certain RPM's when cruising. The diagnostic machine is now saying the misfire has gone.

At idle there is NO shaking, I have also noticed that when revving the car at neutral the revs are quite unsteady between 1000-2000 rpm, its almost impossible to hold the car at a steady 1500 rpm. The shaking also seems to be worse the further down I press the throttle, and also goes as soon as I stop accelerating.

Sorry for the long post but im trying to give as much info as possible, if anyone can help it would be greatly appreciated, you guys seem to know your stuff on here!

 

[James_R]

You could either bite the bullet and have a new injector or wait until the problem is as bad as it was before the loom was fitted.

 

[A.m.C_Ibiza1]

Could be a dodgy MAF? Its possible that this is not related to the miss fire you had before, easy to check, unplug the MAF and take the car for a quick drive with it unplugged, if the judder is completley gone then you know its the MAF!

Hope this helps!!

 

[James_R]

Could be a dodgy MAF?... unplug the MAF and take the car for a quick drive with it unplugged, if the judder is completley gone then you know its the MAF!

Hope this helps!!

that doesnt work anymore and will just drop the car into limp mode.

 

[neilcw]

That's interesting Ricky as I have a PD170 Altea which has had DPF removed and a remap and I've noticed the same behaviour (except the idle bit as I've not tried that). Mine's a manual and if your in the higher gears i.e. 4-6 and boot it going up hill especially the car does accelerate but not anywhere near as much as I feel it should and it judders. It certainly doesn't feel like there's much turbo boost taking place that's for sure

It certainly feels like a misfire so I'm not sure whether this is turbo related or fuel or air related as any one of them could cause these symptoms. Does yours feel smoother if you accelerate downhill like mine does?

 

[devonmikeyboy]

I have several BKD injectors,heads,engines etc if people want any parts for the PD140.

 

[neilcw]

Update: It has been suggested to me that it might be the EGR valve becoming sticky. They get clogged up with gunk over time on a diesel and they need a good cleaning out. You can also blank them out physically and then you need to get the ECU reprogrammed so that your CEL light (or it could be another one) doesn't come on and it will never clog again. I'm currently exploring the options.

 

[rickyquicky]

Thanks for all the replies guys.

Well I took the MAF sensor off a few days ago...the car did seem to run a tiny bit better but there was definately some shuddering still going on. I gave it a clean and put it back on but its hard to really tell a difference.

I havent looked at the EGR yet, will give that a try and feedback what happens as there are obviously others in a similar situation, which makes me feel a tiny bit better lol!