We can take the cars down the car wash if we get time. Or just photoshop em. LOL

Well im better with a jetwash than I am photoshop!! Perhaps if it gets dirty enough it could pass as a black one!! lol

-george i posted this on another thread re a temp sensor,...-------------------------------------------------------------------------------

just a quick one here.. as you know i have had some annoying probs with my r not running right,so i finally bit the bullet(very hard in jan!!) and booked the car in at rt(thanks john) mechs, he said no probs easily sorted,the main cause was the lambda light was on eratic idling loss of power etc
russ told me during a phone call that the coolant temp sensor which i had replaced with the one above was faulty,he said that as i wasnt a genuine bosch/volvo one it couldnt be gauranteed to work correctly!
so for the sake of a genuine volvo/bosch one which is about £10 more i would contact your dealer mate, not saying it wont work ,but 3 months of frustrastion later my cars running perfectly!
once bitten and all that!!

and i will add to this the new lambda sensor aswell!!! not cheapp but the hours of swearing are long gone now!!

also take a fuel pressure check off engine idioling and reving as ull see if its that at fault straight away ,
fuel reg/feul pump ,injectors and a possible ecu change over ,,,,all the best

Thanks to all of the above I may have stumbled across the fault. I was sure that when I checked the fuel pressure last I had this fault and it was 44PSI. Now I'm not sure as the problem was as bad as it's ever been today, so I thought I'd go back and check the fuel pressure again.

Well,,,,,,, I got 36 PSI at the rail at tickover. According to Volvo it's supposed to be 43.511 PSI - 44 PSI at tick over.

Hmm. Looks like this may be the problem. My Question is now,,,,, How can low fuel pressure look so much like over fueling?? Also, is a 8 PSI drop enough to cause this?

And what do I change/check now to bring the pressure back up. Is it worth getting a new regulator or is it time for a new pump or is there anything to be serviced within the pump assembly???


Sorry a lot of questions there but I'm SO CLOSE!!! I can feel it.


LOL


Cheers


George:thumbs_up:

hi pal i can only go on my pressures as they work in bar ,but if needed ill will re fit it 2moz and check ticker pressure and reving to engine to 3,4000rpm and write them down if it may help,
id make sure ur feul filter is replaced first as it maybe full or dirty bits from the fuel tank,then if its same go for a feul reg which im sure ive some ,if needed,u can check ur fuel reg by coupleing it to a foot pump/airline and make sure it blows off at 3bar,,any lower then theres ur fault,
id get a walbro 255high pressure pump ,ive fitted both my vechicals with them and the prime /return fuel very well,

If your 8 psi down at idle just think how much it could be down by when the fuel is in demand at higher engine speeds and the fuel pump can't provide a reserve of fuel. I have known of vehicles which appear to run fine at idle but when the engine speed increases and fuel is in more of a demand a poor fuel pump can't cope and misfiring and lack of power occurs. Bit of a silly question, because I would put money on it that you have anyway, but have you changed the fuel filter? Also did you fit it the right way round? Not that I am sure you can physically fit it the wrong way round on the 850 as I haven't actually looked at mine but a partically blocked or incorrectly fitted fuel filter could also give the problems you are experiencing.

Basically YES

I changed my fuel filter a couple of years ago so it may be due a change. I think I'll go for a new regulator and fuel filter next.

My next question is,,,,,, Is there any filters in the fuel pump assembly???

If so are they changeable???


Cheers

George

If you could do that for me that would be great, then I woudl know what pressure yours is managing.

Cheers

George