Intermittent stutter or misfire, PD130 TDI

[996jimbo]

Advice needed please:

I have a 2001 Passat TDI Sport with the 130 PD engine. Recently it has developed a bit of a misfire which occurs on gentle to moderate acceleration / maintaining say 80mph. It is not present all the time and doesn't seem to be associated with hard acceleration.

Oil was changed about 3k miles ago (by me) and I did the fuel filter at the same time. Total mileage is about 105k. There are no issues with starting or idle (not at the moment anyway) and I don't notice it if I accelerate hard, though I've only tried harder acceleration to clear it a few times so it might just be coincidence.

I used VAG COM to read the ECU but it showed no fault codes on the engine module or anything relevant (fault codes were open speaker circuit and something to do with the alarm/horn).

Any suggestions as to where to start looking?

[macquatic]

Injector wiring loom is a possibility or an injector playing up, try a "search" and you should pick up old threads detailing the problem/fix.
Some injector faults do not show up on VAG-COM but if you can get individual values read you may find the problem.

[passat 130 tdi]

try a maf sensor clean using IPA .

[996jimbo]

try a maf sensor clean using IPA .
I'm not sure I want to chuck beer into the engine :confused:

[passat 130 tdi]

try this instead then. ----- http://cgi.ebay.co.uk/IPA-ISOPROPYL-ALCOHOL-ISOPROPANOL-1-LITRE-min-99-pure_W0QQitemZ140359565639QQcmdZViewItemQQptZUK_BO I_Medical_Lab_Equipment_Lab_Supplies_ET?hash=item2 0ae150147

[Rolo]

Is the misfire regular ie is one cylinder not working, or is it random. If it is the loom or injector at fault then it will be regular. If it is another fault then it may a more erratic miss.

[passat 130 tdi]

my car does this too, through all gears if i back off throttle ever so slightly , apply gas and its ok , im going to change the fuel filter ,clean the maf , try some injector cleaner in liberal doses and see what happens.I'm now thinking some crap was drawn down into the injectors when i had it remapped due the hard acceleration on the rolling road ???

[vroooOOOM]

READ THIS FIRST:confused:
http://www.vwaudiforum.co.uk/forum/showthread.php?t=82798

I changed the injector wiring loom but made no difference, eventualy I found there was blockage in the fuel filter so when excellerating hard it was starving the engine hence causing stutter NOT missfire!!! foot off the gas just cruising and alls well, took me a year to diagnose.:D

Good luck:approve:

[996jimbo]

OK I've checked the faults and it has now logged the following fault code:

18075 - Valve for Pump-Jet: Cylinder 2 (N241): Electrical Malfunction

P1667 - 35-10 - - - Intermittent

So, presumably this could be wiring or pump, what sort of cost might I be looking at?

[Clinterous]

The injector loom costs about £44 from main dealer. It shoud take an hour for someone who knows what they are doing. The first time I changed mine it took 75mins - I reckon less then hour next time.

PD injectors do not fail very often.

[996jimbo]

The injector loom costs about £44 from main dealer. It shoud take an hour for someone who knows what they are doing. The first time I changed mine it took 75mins - I reckon less then hour next time.

PD injectors do not fail very often.
OK thanks for that.

I've ordered a wiring loom now which I'll start with, but if that doesn't work how much for an injector and what sort of job is that to do? Also, do I need a rocker gasket for the wiring loom?

[Clinterous]

No gasket required for the rocker - re use the old one. When you take the old loom out, it is highly likely to snap, but don't worry as the plastic would have gone brittle; the new one will be a bit more compliant. I found the best angle for insertion was 2:00 o'clock, if stood directly in front of the car.

I've not had any experience of removing injectors myself, but have heard about one or two bad experiences. The injectors are expensive. Suggest a search of the forum for an overview of that project.

Check out www.dieselbob.co.uk (http://www.dieselbob.co.uk) for injector info.

I would wait and see if any other forum members come up with any suggestions re the fault codes you have.

[Rolo]

The only trick to use is to heat the new loom up with a hot air gun so that the plastic bends and allows it to be fed in from the back of the head. I put rags down the oil drains so that nothing can fall into the sump. The old loom usually breaks up when you try to bend it.

[996jimbo]

Well I did it this evening. Getting the old loom out was a real bugger, the new one went in fairly easily, though I only had the confidence to bend it because of what I'd read here :beerchug: otherwise snapping the old one would have got me worried.

Slight panic was when I tore my rubber glove and a bit dropped down in to an oilway. I fashioned a sharp hook out of a bit of wire and managed to retrieve it though (phew).

Anyway, the misfire had got more regular but eased with a hot engine so I was confident it was going to be the loom and now the misfire has gone. :approve:

[sirbbrown]

Ive only joined here today and havent posted before,
I have 2002 tdi avb,I have an intermittant shuddering also,on idle its fine but on accelaration its very jumpy and looses power almost like an airlock.if i stop switch of the ignition switch back on and then start it clears the problem, this happens maybe once a day.
could this have anything to do with the pump in the tank loosing back pressure?
I have an old vw1552 would this connect with my passat or would it tell me anything?
Any help would be great....cheers

[martin1810]

Sounds like you are going into limp mode which resets when you turn ignition off. A code read will give you a pointer. Don't know if your 1552 will work or not.

[sirbbrown]

thanks for that i got it plugged in and theres a problem with current on injector 2, i will strip the rocker cover and have a look,hopfully its nothing serious

cheers

[martin1810]

You will almost certainly need a new injector loom. I doubt you will see anything just by looking. Buy a new loom and fit it whilst you are looking. Get the loom nice and warm and bendy in doors before you fit it.

[mcook]

Hello
don't want to hijack the thread but I'm having a similar problem with my Passat 5.5. The car starts fine but as soon as it gets to its running temperature, it starts juddering and the ESP and engine management lights come on, together with the Emissions Workshop error. Restarting the car after 5 minutes or so will clear the judder and the ESP light though the engine management light will remain for several hours/days.

Diagnostics report the following

18075 - Valve for Pump-Jet: Cylinder 2 (N241): Electrical Malfunction
P1667 - 35-10 - - - Intermittent

Happy to accept that it could be the head harness but the one difference in my case is that it started happening with no prior warning, two days after I replaced the radiator about six weeks ago. Is it possible that this is related in some way (that I forgot to reconnect a sensor or because something got wet with all the water that was flying about) or is this probably just coincidence ??

Cheers

Mark

[martin1810]

mcook. It's telling you one injector isnt working properly. With luck this is just the head injector loom and not the injector. Change the loom and see what happens. I doubt you have accidently caused this. Good luck

[mcook]

Just seems a coincidence that a problem that only occurs at temperature happened so shortly after replacing the radiator but I think you're probably right . As it was so cold today, I didn't have any problems with it at all.

Thanks for the reply. I've purchased a new loom today and I'll try and get it in over the weekend.

[996jimbo]

Hello
don't want to hijack the thread but I'm having a similar problem with my Passat 5.5. The car starts fine but as soon as it gets to its running temperature, it starts juddering and the ESP and engine management lights come on, together with the Emissions Workshop error. Restarting the car after 5 minutes or so will clear the judder and the ESP light though the engine management light will remain for several hours/days.

Diagnostics report the following

18075 - Valve for Pump-Jet: Cylinder 2 (N241): Electrical Malfunction
P1667 - 35-10 - - - Intermittent

Happy to accept that it could be the head harness but the one difference in my case is that it started happening with no prior warning, two days after I replaced the radiator about six weeks ago. Is it possible that this is related in some way (that I forgot to reconnect a sensor or because something got wet with all the water that was flying about) or is this probably just coincidence ??

Cheers

Mark
It's the same fault code I had and mine has been absolutely fine for the last few thousand miles since changing the wiring loom

[martin1810]

That fault code is almost certainly due to a faulty head loom. It can be a faulty injector but it is usually the loom, thank God.

[mcook]

Hi all
as intimated by others, this was indeed the cause of my woes. I replaced it about 10 days and over 1000 miles ago and it's been fine ever since.

Surprisingly easy to change too, even for a complete amateur like me. Looks worse than it is so don't be afraid to give it a go.

Many thanks to all for your advice and merry christmas.

[passing]

OK I've checked the faults and it has now logged the following fault code:

18075 - Valve for Pump-Jet: Cylinder 2 (N241): Electrical Malfunction

P1667 - 35-10 - - - Intermittent

So, presumably this could be wiring or pump, what sort of cost might I be looking at?

Take off the cam cover and look at the injector electrical connection. I had the same fault code when for some reason one of teh connectors came loose. The clip may have been damaged previously so that the vibration is causing it to come loose.
The contacts are also in oil and so perhaps a clean will re-establish a good contact.