1.9 TDI misfiring problem

I hope this is the right forum to ask this Q.

I have a SEAT Alhambra (yes, I live in Europe) which has a VW 1.9 TDI (115 HP) engine. It has a misfiring problem that two garages have been unable to solve.

The problem has a 3-day cycle, like this:

1. Day 1: Misfires occasionally until its warm, then goes OK
2. Day 2: Starts misfiring after about 5 mins and runs on 3 cylinders (thats what it feels like to me). After it is warmed up, if I stop and restart it, runs normally
3. Day 3: Starts running on 3 cylinders immediately, and won't go back to 4, however often I stop and restart it

First time it happened (in June), the SEAT workshop said it was dirty fuel. After their "investigation" all worked well for a month.

In July it happened again. This time I was on vacation and a local garage near where we were staying said it was a faulty pump/injector, and replaced it, costing me a bomb.

All went well until a few days ago, when it happened again. Back to the SEAT dealer who is still trying to work out what the problem is.

Has anyone got any idea?

The car is 6 years old and has done about 120000 miles. The weather condirions are normal. I use low-sulfur diesel, but I have been doing so for several years without any sign of this trouble.

Welcome aboard. The more Europeans we have here, the more we learn.

I can't help much but give you my wild guess.

If you are "running on 3 cylanders" that would mean a bad injector. I know of no reason why it would "come and go" in the first couple of days. But that is a possibility.

If it's not as consistent as 3-cylanders, I'd go for an electrical connection or ground. If it's not a pd (I'd ignorant as to the 115hp) I'd check the third injector's electrical connection. I'd also clean all of the grounds in the engine bay. Hopefully, one of our more experienced members on your side of the pond will help more.

This must be a pumpe duse. In the States a couple of folks found that the cam and lifters had worn so bad (from use of the wrong oil) that they were getting misfires. I hope that i not what it is. You may want to look under the valve cover.

Could also be a plugged fuel filter of failing lift or tandem pump.

--Nate

If it is pd engine I doubt that it's cam lobe because it is acompanied by a lott of smoke (that is so far).It looks to me like it is one of wiring conectors on one of injectors.Ihad a lott of those.

Have them pull the valve cover to look at the cam and the wiring connectors there.

Thanks for all the advice guys and gals.

I'm going for a wiring/connector problem. If I start getting a poor connection that starts arcing, I could see it could build up some deposit on the terminals until it broke the connection. Dismantling and reassembling would remake the connection but not solve the original problem of a maybe a loose connection, so it would start over again after a while.

I'll look into it.

Have a good one.

If it was running on 3 cylinders you ould definately know, because it would be really smokey. If it is not a pump duse engine, it might be worthwile to check that there is no blowby of from the injectors / injector sealing washers

Just to say, this is a PD engine. Engine code is probably AJM.

chrisp1 said:

Thanks for all the advice guys and gals.

I'm going for a wiring/connector problem. If I start getting a poor connection that starts arcing, I could see it could build up some deposit on the terminals until it broke the connection. Dismantling and reassembling would remake the connection but not solve the original problem of a maybe a loose connection, so it would start over again after a while.

I'll look into it.

.

Click to expand...

The problem is in conection but on the unit injectors themself.Under the rocker cover is a wiring harness with leads for injector activation.The problem is on terminal for wich you have a code.Pull it out off that injector and open the terminal,tighten contacts and assemble it back again.Notice how the wires are positioned in the terminal so that you dont place them in wrong order.That will take care of missfiring code.

this has fixed my misfire, thanks mikica

No problem,glad to help!

melanie said:

this has fixed my misfire, thanks mikica

Click to expand...

Were you getting a code? If so, what was it?

Ditto whitedog...codes?

If it is bad fuel, get the Euro equivalent of Power Service 911 and apply as instructed the next time it has the problem.

So, 120K miles, not km? Some folks have suggested a lifter replacement at about 150K miles. Any non-spec oil would shorten this interval.
Would pull the valve cover and check for cam lobe and lifter wear as suggested above. Very quick and easy to pull. Sure beats throwing another injection pump or other high $$ part at it.

mikica said:

The problem is in conection but on the unit injectors themself.Under the rocker cover is a wiring harness with leads for injector activation.The problem is on terminal for wich you have a code.Pull it out off that injector and open the terminal,tighten contacts and assemble it back again.Notice how the wires are positioned in the terminal so that you dont place them in wrong order.That will take care of missfiring code.

Click to expand...

Mikica, I don't know if this is a common problem in the US and Canada. But if it is happening, I doubt that VW techs know how to solve it -- they would probably start replacing injectors right away.

If you have time, maybe you could start a new thread dedicated to trouble-shooting PD injector troubles? Just what you know, then others could add to it.

I dont know for other vw techs but Im one of them and I work in Europe.The point is that this a problem on most of PD engines. In some cases injector does fail and has to be replaced but those are a few cases.
There were some rough runing problems on idle but I solved them by adjusting injectors.It is a simple prtocedure.I will make a thread for those who would like to try.Another problem are saeling O-rings on the injectors.You can tell when you see raised engine oil level on the oil dipstick.In earlyer models there was recall on the tandem pump bolts.This is what I can think at the moment.Ill make a list of other thigs and stard a thread.

mikica said:

I dont know for other vw techs but Im one of them and I work in Europe.The point is that this a problem on most of PD engines. In some cases injector does fail and has to be replaced but those are a few cases.
There were some rough runing problems on idle but I solved them by adjusting injectors.It is a simple prtocedure.I will make a thread for those who would like to try.Another problem are saeling O-rings on the injectors.You can tell when you see raised engine oil level on the oil dipstick.In earlyer models there was recall on the tandem pump bolts.This is what I can think at the moment.Ill make a list of other thigs and stard a thread.

Click to expand...

You would be a hero.

Yes, if you do make another thread, please post a link here.

Thank you very much.

whitedog said:

You would be a hero.

Click to expand...

A Serbian hero..

Dimitri16V said:

A Serbian hero..

Click to expand...

I'm down wit dat.

BTW, is your location Denmark or Deleware?

Delaware, not the slower lower , though. No offense Blue Hens

Thnx mikica.... the connectors were my problem as well )

been there already, replaced the wiring harness

hi i had a ford galaxy exactly same like a seat Alhambra or a vw sharan ,when it miss fires
i change the wiring harness to the injectors the car run around 400 miles but started same
problem before it was number 2 cylinder miss fire /malfunction now its change to number 3
any ideas a garage said might be a faulty wiring harness or a injector what you think , i read your messages i do believe that you are a pd engine expert
thanks

Hello! I know this is as old as times topic, but i just wanted to say i did what was given as the solution.
And my misfire is gone!
I had a small stutter and limp mode. Which threw code;
17965 charge pressure control postive deviation.
Found a loose vacuum tube to the egr which was probably the cause.

But then today got a 18075 p1667 electrical malfunction on cyl2.
So i found this topic.
Couldnt get the contacts out of the plastic connector so i just bended them a bit.
Quick job!
Hope this was it and it wont come back tomorrow with a vengeance ;-)

Here's my video on this problem
https://www.youtube.com/watch?v=1WB-ygxOLk4&

kaneelschep said:

Hello! I know this is as old as times topic, but i just wanted to say i did what was given as the solution.
And my misfire is gone!
I had a small stutter and limp mode. Which threw code;
17965 charge pressure control postive deviation.
Found a loose vacuum tube to the egr which was probably the cause.
But then today got a 18075 p1667 electrical malfunction on cyl2.
So i found this topic.
Couldnt get the contacts out of the plastic connector so i just bended them a bit.
Quick job!
Hope this was it and it wont come back tomorrow with a vengeance ;-)

Click to expand...

There's a difference between a small stutter and limp mode and misfiring like the OP is describing.