Revs holding and dropping

Technical questions and answers about the Mazda Bongo

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Superman can't fly
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Revs holding and dropping

Post by Superman can't fly » Tue Jul 17, 2018 6:03 pm

Hi. Having some serious problems. I have just replaced the turbo and egr. As before I was having problems with not getting over 40mph. I've reassembled the car now. I have taken it for a spin when once again been loosing power whilst driving. I parked up raised the revs to 3000 held it for couple of minutes and there it was. It started to reduce my revs. It sounded like it was great 1 minute and the next like the revs were being jumpy. No lights flashing at all. Soon as let off the pedal and reapply the power is there again but does the same thing over and over at different held revs. I'm at the end off my tether and need some serious help please. All filters changed. Banjo clear. No loss off coolant. No hold light of or flashing. Nothing. Any help appreciated.
teenmal
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Re: Revs holding and dropping

Post by teenmal » Tue Jul 17, 2018 9:14 pm

I think you need to have an other go at the filters and your fuel tank. You could also use a test bottle with fresh clean fuel making sure the pump filter is perfectly clean.
Superman can't fly
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Re: Revs holding and dropping

Post by Superman can't fly » Tue Jul 17, 2018 9:18 pm

Will try that tomorrow thanks. Any advice is great right now and appreciated.
mike_glos
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Re: Revs holding and dropping

Post by mike_glos » Wed Jul 18, 2018 8:06 pm

On my year 2000 variable vane turbo, just one of the turbo solenoid valves caused me power loss. First replaced with a second hand valve, which was worst (almost permanent power loss) and then a new one. I have had no further power loss since this fix.

What makes you think it is the turbo itself? I have been told by at least one specialist they are quite reliable. If you've got warning lights showing they should help you determine if its a problem with the Engine Management System.

In my case Premier Bongo have always found that the two warning lights I had showing have always been as a result of a faulty Turbo Solenoid valve.
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Alacrity
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Re: Revs holding and dropping

Post by Alacrity » Fri Jul 20, 2018 2:36 pm

Blocked exhaust system?
35+ years working with autogearboxes - all day every day......for my sins
Superman can't fly
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Re: Revs holding and dropping

Post by Superman can't fly » Sat Jul 21, 2018 11:29 pm

How can I find out if my fuel pump needs replacing
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Doone
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Re: Revs holding and dropping

Post by Doone » Sun Jul 22, 2018 6:38 pm

Not sure if you've checked this - there's a small pipe from the elbow on the inlet manifold, to the top of the diesel pump. Check it's attached properly and not split.

Also, is this pipe is oily? :?:
Allan's closed. We recommend PGS (Plymouth Garage Services) or Mayflower Auto Services in Plymouth.
Superman can't fly
Junior Bongonaut
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Joined: Thu Jun 28, 2018 9:16 am

Re: Revs holding and dropping

Post by Superman can't fly » Tue Jul 24, 2018 8:14 pm

Problem solved... I took the sender unit off today and inside the bottom was some serious carnage. In the tank there were bits of leaves and plenty off bits and bobs floating around. I took the pipes of the diesel filter and blew them through with a compressor. Cleaned the tank out with Karasene and then put some lovely clean diesel in. Put all back together and runs like an absolute dream. Bongo love
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Re: Revs holding and dropping

Post by Bob » Tue Jul 24, 2018 8:32 pm

Sound. =D>

Thanks for update. :)
teenmal
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Re: Revs holding and dropping

Post by teenmal » Wed Jul 25, 2018 11:31 am

Thank goodness ,I have seen this problem for years with diesel vehicles, its called Starvation .


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