PD150 lumpy start up

[andrewjb]

Hi All,

2005 Leon FR+ PD150 ARL.

Car is on 149,000miles, it has EGR delete(incuding asv), organic clutch + SMF and Stage 1 tune.

I serviced the car including fuel filter about 3 months ago.

The car when I got it wouldn't display any temp at all on dashboard, have since fitted a new thermostat and it does display now but if heating is on it drops again quite quickly so looks like an OEM thermostat is needed as it was an aftermarket one.

Anyway during the summer and winter (now) the car will start up lumpy for first 20 seconds, quite a bit of white smoke, less violent if the clutch is in. Car isn't using oil or coolant though. Noticed last few days as well when it starts it sounds like its going to die straight away then it picks up, wasn't doing this in the summer.

No error codes either. i have access to full OBD Eleven so can look at IQ etc if needed. What should I be looking at to try diagnose?

Would glow plugs cause this? Ill try get a video tomorrow morning.

 

[Giberish33]

How long is the glow plug light staying on and what are the outside temps? Glow plugs are possible but I doubt it would cause as much of a ****ty idle as you describe. Sounds more like injector related issues. White smoke is usually un-burnt fuel. It could also be coolant but you said it isn't using any so not likely. I'm not super familiar with obdeleven but most of the important diagnostics need to be done with vagcom.

As for the engine temp dropping off my guess is it is more related to the fact that the egr is deleted. If there is no egr then there is no heat in the egr cooler and the engine doesn't get any additional heat from the exhaust. Living somewhere with cold weather and no erg usually results in very slow heat or no heat. Would have been better IMO to go with dynamic egr tune. I guess you could counter it with a higher temp thermostat but during the summer the engine will run hotter as well and the oil temps will be higher as a result. I'm sure it would be ok to run hotter but I'm not an expert.

 

[Zak3]

Try to check the tandem pump for leakage, also a worn tandem pump can cause injection problem.

 

[andrewjb]

UK based so not extreme cold. I've had EGR deletes on previous PD170, PD80 (1.4TDI) and 1.9 AHU and not experienced the above temperature gauge up and down.

Glowplug light only stays on a few seconds, would say the normal period.

OBD Eleven can do "most" things VCDS can do.

 

[JB05]

Sounds like a faulty coolant temperature sensor. I'm not familiar with the OP's Leon, so this is just a wild guess.

 

[Wilkins]

If the coolant sensor is bad it can be unplugged and the resulting lack of signal will indicate to the ECU that the engine is very cold. That should fix a starting problem but it won’t run well once warm
The thermostat problem sounds like a wrong spec stat to me. Probably 80C. The engine temperature does bounce around but the gauge ignores it as long as it’s over 80, or some such number. I have an EGR delete and it has to be -12 C or colder before the engine won’t stay warm, unless it’s idling in traffic.

Known issues with the PD are vacuum/boost leaks, fuel delivery issues, mostly from drawing air in through aged seals and camshaft wear.

You can isolate most of the fuel problems by setting up a fuel container under the hood, 500 ml or so coke bottle, with both the supply and return fuel lines running into it. Use an inline fuel filter in the supply to keep crud out of the injectors. If that solves the problem look to the upstream system you disconnected for a problem.

Camshafts do go around your mileage if 10 30 oil was used. Search the Mk IV forum as well as Mk V for lots of help diagnosing. Basically pull cam cover and look.

There is a really good PD fuel system diagnostic PDF on here somewhere...

 

[andrewjb]

Anything I can check on VCDS? after a minute or so car runs lovely.

 

[andrewjb]

Video as promised, this is at the end of they day at work so its not sat all night.

https://www.youtube.com/watch?v=UvxjX_0U9m4&feature=youtu.be

You can hear its lumpyness when I go to the exhaust end, if I put clutch in its not as lumpy. After a minute or so it idles nicely.

 

[andrewjb]

any thoughts?

 

[andrewjb]

Bumb, car is still doing this

Cylinder 4 is +2.99 constant, unless I apply throttle lightly then drops to about 2.4

 

[tdi_my live]

Remove the temperature sensor before you start cold. Then it glows for a long time and you can see whether the glow plugs are over.
You write that you now have a single mass flywheel. There is actually a map for this in the file. Did the tuner take that into account?

 

[andrewjb]

I drove it for about 20 mins yesterday then noticed it was 2.35. so it seems to stick at 2.99 when started then after driving goes to within tolerance.

 

[pedroYUL]

What is your torsion angle?

I would start there, make sure you are getting a true zero and not some "fake" zero reading. Torsion can be well off and let you start the car poorly, it will report zero, but because it's outside the range it will read zero.

Then make sure the injector lash is set correctly, and as Danny says check the injector harness as they can become brittle.

 

[Skylake]

Check torsion value, should be between -3 and +3. Then check MAF readings at idle on cold engine, should be around 500mg/str or little less.
If it's all right then take valve cover off and reconnect wirings on all injectors for a few times, make sure they are clean and all. Since you have not so normal smoke at startup, my next guess would be injectors O rings..

 

[andrewjb]

Started a new thread on this! but have replaced injector 4 and fitted new seals. injector 4 will now read +1.5 when warm but +2.99 when cold still

PD150 start up smoke issue

Hi All, Going to start a new thread but had previous old threads on here. Got a PD150 ARL Seat Leon. Car smokes white for ages on start up and sounds rough, it drives fine and after a few minutes of driving the smoke goes away. previously checked the injectors using VCDS and cylinder 4 was...

forums.tdiclub.com

 

[andrewjb]

@Skylake Torsion value on VCDS was -1.5

 

[pedroYUL]

-1.5 is a little retarded, but I don't believe it is enough to cause the engine to stumble that much, it would probably cause extended cranking to fire, but nothing further.

Research how to set injector lash, it is not complicated, and it should bring all of those injection quantities deviations very close to zero.

just watched your video, you probably don't have a bad glowplug, but rather tired ones. I used these guys before that are local to you https://www.gsparkplug.com/

 

[andrewjb]

The car never struggles to start always first time. Glow plugs I will replace for the sake of doing them!

 

[pedroYUL]

It could be harness too. I bet is as brittle as an ice cream cone. My BEW used to make a big puff of smoke at every cold start, until the dealer recalled the old steel GPs (5V) for the new steel sheath ceramic 7V. I highly recommend the ceramic ones.

 

[andrewjb]

I remember my harness on my MK2 Golf with AHU lump, harness broke up when pulled it off. I have ordered some new NGK glowplugs so will do them in a few days.

 

[andrewjb]

Any guide on lash setting up?

 

[pedroYUL]

Here:

Simplified Setting of PD Injector Lash

The Bentley book gives a complicated and problematic method for setting the PD injector clearances. The method is to use a dial indicator mounted onto the rocker, then rotate the engine until the full depth of the stroke is reached. Screw in the adjustor screw until it bottoms out. Then back...

forums.tdiclub.com

 

[andrewjb]

So started it this morning, 14 hours since it was last started. Started it with MAF unplugged, then started it again with MAF plugged in, no difference.

Started with 50% of the smoke it used to.
1 -0.82
2 -1.51
3 -0.87
4 +2.99

Last time it started and was very smokey it had been sat for 2-3 days, I'm starting to think it is the seals on injectors that have gone and thats allowing diesel to leak and sit. I started it last night after it had cooled down for 2 hours and there was no smoke! So I'm thinking 4 was leaking the most but now 1-3 are still leaking.

Might replace seals on 1-3, set the last on all 4 and glow plugs and see what that does.