850 2.5 20v - Very occasional stalling

[Cypher007]

ive use a tyre gauge before. just be careful maybe wear some goggles and do it when the engine is cold. as when you take the gauge off you will get a small amount of fuel squirt out.

[AndyPants]

A minor update to this, second hand fuel pump has arrived - looks ok but not tested it yet. Still waiting for my fuel pump 'spanner' to arrive, might as well use it now that I've ordered it!

Tried my tyre pressure gauge, at cold idle I got 44PSI recorded, but the gauge has now gone to tyre pressure gauge heaven... so not sure how accurate that is but I assume thats probably a healthy reading. Might order a proper one now!

I drove the car back from my mums and it was smooth as silk, but then it is until it throws its toys out of the pram I've now stripped out the rear interior ready to swap out the pump at least.

[AndyPants]

Finally(!) got round to changing the fuel pump yesterday for the second hand one. Was fairly straight forward bar the fuel hoses being a pain to get off. Managed to get one off using some trim removal tools but the other wouldn't budge. In the end I used some angled circlip pliers to gently tug it off!

The new, second hand, pump is definately noiser than my original. With a high pitched electrical buzzing sound, but it seems to work well enough and the car seems happy thus far at least. Tried putting another £20 quid fuel in and the noise has remained the same. The noise will probably be ok when I reinstate the plate and boot trim.

I haven't changed the fuel filter yet since I thought I'd see how the car goes since the old filter is only 2 years/7k miles old anyway and the old pump may not be the culprit. The fuel filter is also almost as expensive as the replacement fuel pump The old pump wasn't noisy at least so I doubt there was a blockage

[john850kershaw]

Hi if the fuel pressure regulator has failed what can happen is that the car is hard to start and if you get it running it will over fuel causing bad running and black smoke out of exhaust, the diaphragm splits and lets fuel pass and it goes back into the inlet manifold, i would first try to get a fuel pressure gauge and see what pressure you have and just wait and watch to see if the pressure drops off, since you have replaced the relay you can rule that out pretty much.

[AndyPants]

Originally Posted by john850kershaw

Hi if the fuel pressure regulator has failed what can happen is that the car is hard to start and if you get it running it will over fuel causing bad running and black smoke out of exhaust, the diaphragm splits and lets fuel pass and it goes back into the inlet manifold, i would first try to get a fuel pressure gauge and see what pressure you have and just wait and watch to see if the pressure drops off, since you have replaced the relay you can rule that out pretty much.

Thanks for the suggestion. I may have to get myself a proper fuel pressure gauge, especially if the problem re-surfaces. It basically always runs fine apart from when it very rarely fails to start/misfires/stalls with no real warning. I certainly haven't seen any black smoke or smelt anything too untoward.

Current plan is to swap out the fuel filter to be on the safe side and give it a full tank of fuel to see a) whether it 'bleeds' out the top over night b) whether it acts silly after filling up like it did sometimes before.

[7 Seat Sports Car]

I know its a different car entirely and for what its worth, my 99 V70 exhibited similar stalling issues and before it got really bad also felt lacking in acceleration. There was also a whine from the pump.

A new fuel pump (approx 80 quid from PFV) solved all the issues in one go. Hope you get some joy and the issue stays resolved.

[AndyPants]

Originally Posted by 7 Seat Sports Car

I know its a different car entirely and for what its worth, my 99 V70 exhibited similar stalling issues and before it got really bad also felt lacking in acceleration. There was also a whine from the pump.

A new fuel pump (approx 80 quid from PFV) solved all the issues in one go. Hope you get some joy and the issue stays resolved.

Thanks, hope I have the same level of success! Thus far it's performing brilliantly and after filling it up with a full tank I've left it a couple of days and no slight weeping of petrol out the top of the fuel pump housing and no smell of petrol like before! Will drive it to work for a bit now and see if it behaves Also noticed the gauge hasn't dropped like it usually does after standing with a full tank...

[AndyPants]

As an update, filled it up again this week and since swapping out the fuel pump it has been absolutely perfect! Fingers crossed, but I think it's sorted The car is driving better than it ever has in my 5+ years of ownership.

[AndyPants]

Hopefully a final update to this thread.

The issue returned in November/December time last year... started and ran perfect when cold. Started to miss on idle when hot and would cut out/miss badly with jerky throttle movements when hot. After much prodding around I couldn't find anything wrong and with so much replaced I was running out of possibilities.... So the next logical thing to do it to re-look over the basics. It already had new spark plugs, HT leads, coil etc... etc... the distributor cap and arm had also been replaced with genuine items - fairly recently I thought until I looked at my history and found it was about 4 years and 15k miles ago...

Inspecting the cap I found a fair bit of corrosion on the cap points and rotor arm. Gave it a clean up with sand paper and electrical contact cleaner. It now it runs like a dream, hot or cold.

So lesson learned, I will now inspect the distributor cap every couple of years or if starts to act silly again!

Passed its MOT a few weeks ago. Over 21 years old and no advisories Although I did need to replace one of the remaining original '96 control arms