Stalling ONLY after a long run.

[skater]

Didn't want to hi-jack other stalling topic as that sounds different
to my problem.

After a long steady run and I'm slowing , gradually the revs drop towards
idling speed but then sometimes they will keep dropping producing a shudder like
manual with clutch up.

If I put it in N the shudder goes ( as you would expect/hope ) but the revs keep dropping.
With a deft bit of footwork and D or N selection I can keep it going.

The first start after this will take a bit of cranking but all subsequent starts are instant,
fires up nicely in the morning etc.

Just had new ATF and filter clean, fuel filter cleaned and oil change.

Stalling happened twice before service and once after ( so far ).

Any ideas please ?

[mikexgough]

Without seeing it for sure...... the symptoms sound like your having a fuel starvation problem at certain times , caused possibly and I say possibly ....to air in the fuel line somewhere .....

My theory is....that your on a long run...revs are up....slow for a motorway junction.....lift the throttle & engine is still using the fuel that is in the pump, at that time too with shut off throttle....air is coming into the system

My reason for suggesting this is....... you say it starts after some cranking....which sounds to me like your bleeding the air from the system....

[daveblueozzie]

There has been the odd occasion where the vacuum in the diesel tank is too much, just releasing the fuel cap sometimes does the job.
Other than that, possibly a fuel pump problem.

[cynfal]

Ive only just had the same problem. I had to replace the fuel injector pump. I had tried all the other options but in the end I had to take the van into a local Diesel specialist to cure the problem. I managed to get a second hand part from a breakers but the labour cost of removing the old pump and fitting the new pump was close to £400 (Part cost £180)
The van runs perfect again now and has just past the MOT last week
Good Luck
Gareth

[missfixit70]

Did you check the banjo fuel strainer? factsheet in the members area.

[skater]

Thanks for all the replies.

Yes, checked banjo first then had other service items done.
I was also thinking air in the system.
I was driving on the A303 yesterday, Andover to Honiton.
There are a lot of roundabouts for slowing down in the " off throttle, fuel in the pump"
situation but problem only happened once.
Also it revs up easily when I quickly knock into N to avoid said stalling situation.
Tip of the iceberg maybe.

Don't like the sound of a new fuel pump.
Bongo runs really well 99.99% of the time, pulls strongly etc.

Gareth, did you have any other symptoms?
I've been out and about today doing shorter runs and the engine starts instantly every time.

[cynfal]

All the symptoms that your having-but got worse and worse over time until it stalled coming down a hill, and when the engine cuts out the steering went and the brakes got very hard. Local garage that I tried first changed the fuel filter/cleaned the banjo filter/changed the seals on the fuel pump but it was the fuel injector pump that was faulty in the end. Local journeys where fine but as soon as the engine was running at normal temp it would cut out at roundabouts etc. Im glad ive sorted it all out now
Gareth

[skater]

Doh!
That will be something to look forward to then.
Have experienced the heavy steering and brakes already, only once tho'
( in this vehicle anyway ).
Managed to keep revs up in N last two times. Luckily it wasn't anywhere
busy.

[roofraisers]

Just in case you need it, but it's at the other end of the country.

http://cgi.ebay.co.uk/Mazda-Bongo-Fuel- ... 1c1437577d

On the up side you would get full value for money on the postage costs.

If you do take your own injection pump off, get it sent to a fuel injection specialist workshop for full pressure test & diagnosis, they may be able to repair or adjust an internal fault.

Nigel

[skater]

thanks Nigel, hadn't checked E-bay yet.

I've found that sometimes things fix themselves if you ignore them.
Like when my speedo stopped working on 2 occasions a couple of
years ago. Did nothing and it's been fine since, touch wood

Same with our dish-washer actually.

No it doesn't have a speedo, before anyone asks

[francophile1947]

Have you checked daveblueozzie's suggestion yet? A blocked cap could easily account for a vacuum in the tank, especially as it happens after a long run. Mine clogs fairly regularly, due to using cooking oil, and I have had symptoms similar, but not as bad as yours.

[skater]

good point , thanks, I'd forgotten that one.
Have checked in the past but not straight after a long run.
I'm using veg oil too so will look at it shortly.

[gmaczbongo]

Have you tried running on diesel only.
Or at least a stronger diesel/cooky mix.

[skater]

The last long run I filled up with +- 45L diesel on top
of a 20% veg/diesel mix.
Maybe on a long steady run the veg has a chance to settle to the bottom a bit?

[francophile1947]

Maybe on a long steady run the veg has a chance to settle to the bottom a bit?

Nope - it stays mixed.