Member Since: 23 Nov 2021
Location: DRAMMEN
Posts: 6
Cold start - LPFP related?
I experience that I have to crank the motor for some time until it starts. Second time I start it starts immediately. The car runs like it should after startup, revs fine immeditately, power is very good and no fault codes. D3 MY06 with new glow plugs/relays/fuses, new battery etc. EGRs are blanked off and butterlfy removed. ECT are changed. FBH can run for 30 min, but I still have the problem .
With these things sorted I'm trying to figure out if start problem is caused either by:
-Low current draw / poor performing LPFP. My LPFP pulls around 4 Amps. Fuel comes out the valve on top of the motor upstream the HPFP. Is doesn't spray out though. I'm reading it probably should be a bit higher for a D3. The weather on test day was around 1 C so not too cold.
-EGR. I have blanked off EGR. Can the EGR stuck in a position give me problem or is that out of the question when it is blanked off? I have a P0405 fault code.
-Fuel Injector. Cylinder 5 at min limit. Cylinder 6 at max limit but within operational window... Codes P02AF , P02AA, P121A
-MAF: I have a P0100 and P0100 code here. Can this be it? I have no problems when driving the car. Full power and no codes. Took it out to see, but haven't cleaned.
Will highly appreciate any help on the theories for my problem..
Jostein
15th Dec 2021 12:05 pm
LittleG
Member Since: 21 Sep 2013
Location: Wombourne
Posts: 391
Member Since: 06 Mar 2017
Location: Lost
Posts: 4939
4 amp draw is good enough, I've many times seen a D3 run on less than 3 amps! You might have a look at the flow rate just to confirm it's healthy. (1.5 ltrs p/m) A good quality fuel filter is important here!!
Blanked EGR's will have no effect on starting, a leak in the pipework/manifold will though. Check for leaks and check the connectors on the MAF. Injectors could be an issue but they'd need to be quite bad, especially with a Webasto warmed engine.
Given the info you have provided my money would be on the MAF, an air leak, or both, but ideally you'd need to address the injector issue too. yµ (idµ - eAµ) ψ=mψ
15th Dec 2021 2:07 pm
holejos
Member Since: 23 Nov 2021
Location: DRAMMEN
Posts: 6
Thanks! Good to know that my LPFP might be ok then! I changed diesel filter this summer. There was no change to the starting. I did the blanking myself and there were no big change before or after this was done.
I'm also hoping it is the MAF although I don't understand why I'm not getting more trouble with this when driving. I thought the engine would have given me errors if the MAF wasn't working (?)
I will first check some live monitoring for air flow etc. as you point out.
And yeah - the injector could contribute, but understand they aren't too bad.
I'll hook up the IID tool once I get the time for a proper check.
15th Dec 2021 6:23 pm
PROFSR G
Member Since: 06 Mar 2017
Location: Lost
Posts: 4939
Well you do have codes logged for the MAF, in any case the PCM will have default value to fall back on if the MAF meter is faulty.
Check for leaks, and the connections too as issues here are both common enough.yµ (idµ - eAµ) ψ=mψ
15th Dec 2021 6:28 pm
holejos
Member Since: 23 Nov 2021
Location: DRAMMEN
Posts: 6
Where is potentially this leak if it contributes to the problem? Air intake?
16th Dec 2021 12:08 am
garrycol
Member Since: 06 Dec 2010
Location: Canberra
Posts: 1119
I appreciate you have recently worked on the glow plugs but this is sounds like a glow plug issue more than anything else. (an additional clue is the engine starts OK second time as the engine has a bit of heat in it)
It gets cold where I live in winter (not as cold as you) and I have a similar issue. What I do it switch ignition on until glow plug light goes out the switch off and ignition back on until glow plug light goes out - I do this three time when cold, so cycling the glow plugs three times - engine normally works first time and if with a little throttle runs smooth.
Garry
Last edited by garrycol on 16th Dec 2021 2:27 am. Edited 1 time in total
16th Dec 2021 12:47 am
PROFSR G
Member Since: 06 Mar 2017
Location: Lost
Posts: 4939
holejos wrote:
Where is potentially this leak if it contributes to the problem? Air intake?
See the attached PDF and hover over the sticky notes for a visual on the following.
The pipework from the air flow meter (MAF) across the top of the rad pack to it's intermediate joint down alongside the rad cowling. This continues alongside the chassis rail to the rubber joint at the induction side of the turbo. This is not easily accessible as it will mean nsf wheel off as well as the heat shields to check the small rubber joint and clips are OK. So only go there if all else fails to yield a result.
If you want to do a thorough inspection to include the charge side of the turbo. (you don't have dtc's to indicate an issue here) There's the joint between the plenum and the throttle body. The 2 joints between the throttle body and the inlet manifolds (2 large O rings). Then there's the inlet manifolds themselves for which ideally a smoke test is normal practice. However, with a judicious and very careful application of brake cleaner lightly sprayed on the manifolds will reveal any leak, as it will momentarily affect the idle speed if it's drawn into any cracks. (only do this on a cold engine!!) Then there's the pipes from the turbo through the intercooler and up the OS of the rad pack to the throttle plenum. I'll admit it's overkill, but if you have never been in there it will be no harm to check all is well should you feel up for it. (not a big job)
Member Since: 06 Mar 2017
Location: Lost
Posts: 4939
garrycol wrote:
I appreciate you have recently worked on the glow plugs but this is sounds like a glow plug issue more than anything else. (an additional clue is the engine starts OK second time as the engine has a bit of heat in it)
It gets cold where I live in winter (not as cold as you) and I have a similar issue. What I do it switch ignition on until glow plug light goes out the switch off and ignition back on until glow plug light goes out - I do this three time when cold, so cycling the glow plugs three times - engine normally works first time and if with a little throttle runs smooth.
Garry
Yeah I'd agree, although he says that after a 30 min burn with the webasto the starting is not improved.
That should absolutely not be the case, because you can disconnect the glow plugs completely on a -10°C morning and the D3 will fire first pick of the key if the webasto has been burning for that long.
Injectors are looking very suspicious though, but I suppose start with the "cost nothing" approach and go from there.yµ (idµ - eAµ) ψ=mψ
16th Dec 2021 2:53 am
holejos
Member Since: 23 Nov 2021
Location: DRAMMEN
Posts: 6
Thanks again for all help! This is really good allowing me not to jump on any conclusions. Since the car runs so well apart from the first start I have a feeling it might we a small thing (like MAF and leaks), but also the theory of the poor diesel flow could be a theory. (since the fuel is there on the second start with a hot'er engine)
I will start with the "cost nothing" approach and check for air leaks. I don't get any reading on the MAF (yes I also cleaned it yesterday), and at the same time I know that the intermediate joint alongside the rad cowling is poor. It seems it doesn't stick well in the rubber seal and there is some kind of unevenness in the cover where it is fixed and this holds back a proper seating. Maybe once the bonnet is closed it is better ?? . I will try to start the car with forcing this joint together.
Member Since: 21 Sep 2013
Location: Wombourne
Posts: 391
Out of curiosity, what does the coolant sensor report at cold and then after the FBH has run for half an hour or so?
16th Dec 2021 12:12 pm
holejos
Member Since: 23 Nov 2021
Location: DRAMMEN
Posts: 6
See my injectors live data... Idle...on the limit...
17th Dec 2021 12:28 am
PROFSR G
Member Since: 06 Mar 2017
Location: Lost
Posts: 4939
No 6 is way too low and 4 is too high, injectors will try to compensate for a another's abnormal operation. You could try swapping and see how the numbers look then.
Bear in mind though, some of the cylinder numbers and injector numbers are not the same.
NB. As seen from the driver's seat in a RHD vehicle!!
Driver's side front cylinder is cylinder No'1 injector No'1
Driver's side centre cylinder is cylinder No'2 injector No'3
Driver's side rear cylinder is cylinder No'3 injector No'5
Passenger side front cylinder is cylinder No'4 injector No'2
Passenger side centre cylinder is cylinder No'5 injector No'4
Passenger side rear cylinder is cylinder No'6 injector No'6
Firing order is 1 4 2 5 3 6
The injector fuel pipe unions are designed to be a "one shot" only component and are to be renewed if opened. That said, you can reuse them but you must be careful not to overtighten or you'll crack the coupler. Either way, it goes without saying a leak from this very high pressure system is extremely dangerous if it makes contact with you. Proceed with due care and diligence! Use new copper seat washers.yµ (idµ - eAµ) ψ=mψ
17th Dec 2021 1:41 am
holejos
Member Since: 23 Nov 2021
Location: DRAMMEN
Posts: 6
Thanks PROFSR G - much appreciated.
I have read up on other posts on this, but still not clear in my head if I have to change all 6 or could change the two in question.... The cost is fairly high for my old LR...
17th Dec 2021 11:07 am
PROFSR G
Member Since: 06 Mar 2017
Location: Lost
Posts: 4939
You don't need all six, two at most for the moment. You could try swapping No'6 with another and see how that affects the balance. You might get away with one for now.yµ (idµ - eAµ) ψ=mψ
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