P38 starting problems

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that are working
Exactly right the M51 Diesel engine will struggle if 2 or more glows are not functioning...

Being very careful as the amp draw of the glows is quite high, you could direct power the glows (Wammers/Datatek will advise best course) and heat them for 6-10 seconds or so and immediatly try and start from there!

Duration of glow lamps is controlled by glow relay subject to reading from ECU temp sensor. If you have a couple of duff plugs starting will be effected. You really need three working plugs on three consecutively firing cylinders to get a start even then it will be lumpy. If you have duff plugs and the ECU temp sensor has gone down, as it reverts to a 50 degree default, the glows that are working are not lit long enough for cold start. The fuel temp sensor can also effect hot starts if it is reading to low.
 
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Well I've already changed all 6 plugs. Will check there's is the required voltage to each plug first. Then go from there. Would having the FIP reconed help??
Not unless you know it has a problem, back to diagnostics.
If it starts on Easy Start and then runs OK, IMO it's unlikely to be the FIP, Wammers will know for sure.
 
It's starting to do my head in now. Lol. Perhaps when the new battery comes it will be a different story.. I ordered the one suggested earlier on from battery megastore
It's a matter of eliminating things in a logical order. So, when you have a new battery, check the voltage at the glowplugs, should be close to 11 volts, if OK check the actual glowplugs, Check there is no air in the fuel system, check the lift pump is working, check the cranking speed is good, check the engine temperature sensor and so on.
 
I will check voltage to all the plugs.. All 6 plugs are brand new to can rule them out. I can't see any air in the clear fuel line, someone has fitted a valve in the middle of it though and it looks pretty poor on the connections. Perhaps that could be hindering flow? But when it eventually starts there's a fair amount of smoke just for a second or so, I would say un burnt fuel then when it's running fine it clears up. And when it don't start and a squirt of easy start applied it then fires after 5 - 10 seconds and runs fine after that. Cranking speed could probably be faster though.
 
I will check voltage to all the plugs.. All 6 plugs are brand new to can rule them out. I can't see any air in the clear fuel line, someone has fitted a valve in the middle of it though and it looks pretty poor on the connections. Perhaps that could be hindering flow? But when it eventually starts there's a fair amount of smoke just for a second or so, I would say un burnt fuel then when it's running fine it clears up. And when it don't start and a squirt of easy start applied it then fires after 5 - 10 seconds and runs fine after that. Cranking speed could probably be faster though.
Were the new glowplugs cheapos or OEM? Cheapos are a well known cause of starting problems, the need to be the correct part.
Slow cranking is also a major cause of poor starting.
 
They were britpart ones. £34 inc vat... But cranking speed does seem a touch slower than I would expect. Should turn quicker with the new battery.
Britpart are not know as ****part for nothing, the Chinese glowplugs are useless. You need Delphi, Beru, NGK or Bosch and the correct ones for the M51 engine..
 
Battery arrived.. Fitted.. Hot starts no better, but I've taken off the hot start fix so perhaps I should put that back on?

Will try later for a cold start when it's cold enough to put the glows on..

I don't think it's a fuel issue, there's pleanty of un burnt fuel coming out when it finally starts
 
Also lastnight when I was manoeuvring in tight spaces it kept stalling. Could that be linked?

I'm leaning towards timing chain stretch now

You really need to get diagnostics on this. You will likely get a fuel quantity fault coming up. If you have had a lot of water in the fuel it may have effected the feedback pot on the quantity servo. Fuel temp sender in pump can effect hot starting also. If it is giving a constant low temp not enough fuel will be injected in hot start conditions. Until you get diag on it you are just guessing. Chain stretch maybe be playing it's part. You need diag to tell you how far it is out by checking modulation. Does the MIL lamp ever flick on whilst driving? It sounds to me like you maybe spending what you paid for the car on a new injection pump shortly.
 
Yeah I fear this could be an expensive one.... No lamps flicker on while driving. What is the mil lamp?

Would it be beneficial to buy one of them nanocom things? Can they read live data?
 
Yeah I fear this could be an expensive one.... No lamps flicker on while driving. What is the mil lamp?

Would it be beneficial to buy one of them nanocom things? Can they read live data?

Yes they read live data. MIL (Malfunction indicator lamp) is the illuminated injector you should see when ignition is switched on. Should go off after ECU has done it's self checks. At least if that is not flicking on that is a good sign. With diagnostics you are looking for a modulation of 45 to 55% with a warm engine at idle. Any more than that and the timing solenoid is being over worked to correct incorrect static timing. Which basically means the injection pump static has shifted due to chain stretch and the pump needs timing. But if you have not got the special tooling to do that, you would have to get someone with it, to do it for you. Guessing is not an option. Correct static is 0.90 mm +- 0.02 mm lift on cam at TDC.
 
You say that should illuminate when ignition on then go out? I don't see that lamp at all.

To right side of dash display. Should come on as bulb check when ignition is turned on and go out when ECU has done it's self check. Maybe a bulb would sort that out.
 
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