hi all

could really do with some advice - ever since i got my range rover back in may 2010 it has had a small starting issue when its warm, all through winter i have had no problems what so ever when starting. The problem happens only once the engine has warmed up then stopped for a while e.g. gone shopping, etc.... when i come back to start the engine it sometimes has trouble starting, the engine turns over for 3-5 seconds then starts then sometimes it will stall straight away sometimes the oil light will flicker when starting but the oil level is on full and there are no oil leaks and the engine has no issues once running. When you turn the key again it will start straight away. First thing in the morning there is no problems at all, it only happens once then engine has warmed up, and if its warm weather. I have a faultmate diagnostic system and there are no registered fault codes in any of the ECU's - i was thinking that maybe the MAF sensor might be faulty but if it was should it register as a fault in the ECU? The car had a brand new land rover battery a few months ago so its not that

The engine is the BMW 4.4 V8 M62 engine.

Any help would be great, i really want to get this sorted as its the only real problem i have on the rangie that really worries me when it happens.

Matt

I can't really tell you why, but my first thought is Crankshaft position sensor. It's just ringing a bell with me, I'm sure I had a warmstart issue cured by CPS. Also the CPS wasn't throwing up a fault code.

I think I have a spare MAF if you need one. Tried replacing the MAF on my 4.4 but it didn't make a difference. Range Rover-less at the moment - Pining!

like boz not sure but fuel vapour or fuel sensor spring to mind... ... - .- -.




Y. O. L. O.
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What if you leave the ign on for 5 seconds before starting? This will return the fuel in the rail back to tank and replenish with cold?

This would rule out the fuel turning to vapour? 

dan_uk_1984 wrote:

What if you leave the ign on for 5 seconds before starting? This will return the fuel in the rail back to tank and replenish with cold?

This would rule out the fuel turning to vapour?

just been looking on the internet about the camshaft position sensor but most things i have read say that there should be some error codes stored.

Tried waiting 5-10 seconds for the fuel lines to fill didn't solve anything, I will record a video of the issue so you can see what it does.

Matt

I would say it's a CPS fault

mattstevenson2005 wrote:

just been looking on the internet about the camshaft position sensor but most things i have read say that there should be some error codes stored.

heres the video of an example of the starting issue, it struggled a little in the video but it has been much worse than this in over the last few days.



Matt

Another avenue I would investigate is the coolant temperature sensor, the idea of the sensor being that when the car is actually starting from cold the sensor senses this and tells the ecu to provide additional fuel (basically like the old choke system).

If this sensor stops working correctly it can fool the ecu into believing that the car is always starting from cold (even when it isn't, this means the ecu is telling the injectors to pump in a richer fuel mixture than is needed.

No fault code will be logged as the sensor output will still be within it's parameters (albeit stuck at it's lower parameter).

The good news is that a temp sensor is usually cheap and easily fitted, you can even test the sensor using a multimeter (looking for two different values for hot and cold) look up the following page for further info http://www.aa1car.com/library/coolant_sensors.htm.

Hope this is of some use.

i think it may be the maf sensor ...you could try cleaning the maf so that you could at least rule it out  "RANGEISM WILL NOT BE TOLERATED"
www.futuresecurityservices.co.uk
Pretlove says , '' I want my car back "

A faulty MAf causes rough running but doesn't cause it not to start

mattstevenson2005 wrote:

hi all

could really do with some advice - ever since i got my range rover back in may 2010 it has had a small starting issue when its warm, all through winter i have had no problems what so ever when starting. The problem happens only once the engine has warmed up then stopped for a while e.g. gone shopping, etc.... when i come back to start the engine it sometimes has trouble starting, the engine turns over for 3-5 seconds then starts then sometimes it will stall straight away sometimes the oil light will flicker when starting but the oil level is on full and there are no oil leaks and the engine has no issues once running. When you turn the key again it will start straight away. First thing in the morning there is no problems at all, it only happens once then engine has warmed up, and if its warm weather. I have a faultmate diagnostic system and there are no registered fault codes in any of the ECU's - i was thinking that maybe the MAF sensor might be faulty but if it was should it register as a fault in the ECU? The car had a brand new land rover battery a few months ago so its not that

The engine is the BMW 4.4 V8 M62 engine.

Any help would be great, i really want to get this sorted as its the only real problem i have on the rangie that really worries me when it happens.

Matt

Just a thought as I had the same issue a couple of years back --- I would check the Fuel Pump !

does any one know a way of testing the fuel pump to make sure that it is this that is causing the issue? - just looked at the price and they are VERY expensive - although i could use a modified X5 part if the worse comes to the worse.

Matt