Fuel Problem

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johnbhoy

Fuel Problem

Post by johnbhoy » Thu Jan 15, 2009 6:00 pm

Just after Christmas, I noticed that I couldn't go above 3000 revs, which was annoying, but not undrivable.
Now, it has reduced to 2000 revs, which is no good.
My local garage says he thinks it is the fuel pump which is acting like a governor, and only supplying a restricted supply of fuel.
Are there any common problems or can anybody point me in the right direction?
Thanks in anticipation,
John.
francophile1947
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Re: Fuel Problem

Post by francophile1947 » Thu Jan 15, 2009 6:09 pm

Welcome to the madhouse :D - don't forget to put your location in your profile as somebody local may be able to help.
Common causes of your symptoms are a blocked fuel filter, blocked strainer in the banjo union to the fuel pump and leaking O rings in the fuel pump (are there any signs of a fuel leak behind the pump?)
If you have the Winter version of the Bongo (it'll have 2 batteries if you have), it could be a stuck valve in the exhaust, or you could just have caught the switch with a picture of an engine on it.
John
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mikeonb4c
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Re: Fuel Problem

Post by mikeonb4c » Thu Jan 15, 2009 6:41 pm

I think Franco has covered main options to try, except not sure about leaky O rings as I had tthose and it didn't cause any performance change (just a slow drip of diesel, and you'd soon know if it was more). Other possibilities (based on what I've read on here, but I'm no expert):

- Blocked air filter or intake (people have had things go/get stuck down the intake under the bonnet)
- Turbocharger problems
- Throttle Positon Sensor faulty (I'm not actually sure this is relevant but have a search and read up)

Good luck - keep us posted
francophile1947
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Re: Fuel Problem

Post by francophile1947 » Thu Jan 15, 2009 6:51 pm

mikeonb4c wrote:I think Franco has covered main options to try, except not sure about leaky O rings as I had tthose and it didn't cause any performance change (just a slow drip of diesel, and you'd soon know if it was more).
Neither am I Mike - I just seem to remember someone with a bad leak was drawing air in - probably total rubbish :lol: :lol:
John
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mikeonb4c
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Re: Fuel Problem

Post by mikeonb4c » Thu Jan 15, 2009 6:53 pm

francophile1947 wrote:
mikeonb4c wrote:I think Franco has covered main options to try, except not sure about leaky O rings as I had tthose and it didn't cause any performance change (just a slow drip of diesel, and you'd soon know if it was more).
Neither am I Mike - I just seem to remember someone with a bad leak was drawing air in - probably total rubbish :lol: :lol:
Ah! You could have a point there - hadn't thought of that. #-o OK add that one in then I reckon
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Re: Fuel Problem

Post by The Great Pretender » Fri Jan 16, 2009 12:59 am

mikeonb4c wrote:
francophile1947 wrote:
mikeonb4c wrote:I think Franco has covered main options to try, except not sure about leaky O rings as I had tthose and it didn't cause any performance change (just a slow drip of diesel, and you'd soon know if it was more).
Neither am I Mike - I just seem to remember someone with a bad leak was drawing air in - probably total rubbish :lol: :lol:
Ah! You could have a point there - hadn't thought of that. #-o OK add that one in then I reckon
8)
To draw air if it is from the pump it will be from the front seal (behind the drive belt) as this is where the pump produces negative pressure (sucks the fuel in).
All other connections from there to the tank could also 'suck' in air as the whole line is negative.
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Re: Fuel Problem

Post by bigdaddycain » Fri Jan 16, 2009 1:01 pm

If i understood it correctly, the leaking pump was quite severe, i know fuel pressures are pretty high with turbo diesels, and a significant leak could cause insufficient fuel pressure to atomise the fuel correctly at the injectors...or summat else might be broke.
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