p38 4.6 not starting need help

hi guys i got a range rover 4.6 p38 gems

its currently not starting up

i originally thought it was the fuel pump which i have swapped with a different and it still does the same

i have checked when i turn the ignition on i can hear the fuel pump priming

i have tried disconnecting the the air intake at the back for the air box and spraying carb cleaner in the air in take and then trying to start the car it starts and will continue to stay on until i decide to turn it off

when i try to start it again after you have to repeat the same process to get it started

i have checked the fuses they look all good

one other thing i have noticed is when i put the air intake pipe back it wants to turn off but when left off it stays on could this be the problem or is it a sensor

Is the fuel rail pressurising ???...Check at the "Tyre" type valve on the rail, petrol should p*ss out when depressed and ignition switched on.

Does it idle ok once its running? Does it start with the throttle open at all?

Hi mate last time I checked the rail the fuel was coming out fast


If the throtte is open fully while trying to start with out the carb cleaner it doesn't want to start

After starting it idles and drives normal on LPG only on petrol you have to keep the air intake disconnected from the air box as it sucks slot of air

jus a update i can fully drive it if i start it by spraying carb cleaner in the air intake and switch over too lpg

when i drive it on petrol i can only push the pedal down a little bit because more you press the pedal the more the engine starts to die as you back off the pedal the engine comes back to normal idle

the problems seems to be more the petrol side because i can drive on lpg

is it single point lpg?

check maf sensor is ok


check for obvious damage to air intake pipes try taking filter out of the air box

check the air intake to the air box hasnt become blocked

hi mate its a multi point bigas system

i have checked the pipes they seem ok il try and check the airbox to see if its not blocked

it could be well out on the petrol trims, have you got acces to a diagnostics kit? where abouts are you?

Hi mate I'm in Kent near bluewater do you know any 1 with a kit that can help near me thanks

mate how can I test the maf sensor to make sure it's ok I took my range to a mte who has a snap on diagnostic computer the only error his comp picked up was faulty maf which showd up 3 times can this cause starting Issues?

when you get it running on petrol get it warm get some body to keep it running and unplug maf. it should run normal with it unpluged, if its faulty

hi mate it will continue to run with it disconnected but you cant drive it as the engine shutters and stalls when you rev it too much in gear when driving

you can rev it fully when its in one place parked

i think its def the maf aswell would it be a good idea to buy a replacement one off ebay as theres a few companys that sell a replacement part for the p38 but its not the genuine sagem one but a exact replacement part....

any one got one lying around or have broken a p38 recently

tbh i only paid£70 for new one. you could end up buying one as bad as the one you have

were did you buy your one from i been looking to buy a replacement one from ebay readiing around on the net alot of poeple say the one off ebay are **** you should buy the original sgem one i guess they wont be selling them if they didnt work

i found this one on ebay Range Rover Discovery air flow meter sensor.ERR5595A on eBay (end time 24-Dec-09 09:19:01 GMT)

DJ_B4L said:

i found this one on ebay Range Rover Discovery air flow meter sensor.ERR5595A on eBay (end time 24-Dec-09 09:19:01 GMT)

Click to expand...

That will make it run badly,better to find a S/hand original from a breaker.

yeh thats what im thinking of doing have you had the experence of buying one off ebay and trouble with it?

thats not what you need you need the senser that plugs in to it. i got mine from local indy, hope this helps

I've got a Lucas 20AM MAF that i bought off ebay as an 'upgrade' for my 3.9.

I never got round to fitting it so can't swear if it works but the guy that sold it to me said it was fine. If it suits you can PM me.