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Won't advance in power to revs

Posted: 23 Oct 2013, 09:10
by 1_eyed_jim
Driving to work this morning I couldn't get over 25mph! And that was really pushing it. Hills I normally climb at 45 in 4th was reduced to 1st/2nd 10mph!

When you press the accelerator the engine noise dips but will not advance??

I've checked the HT leads are secure.

Help please!!

Thanks

Re: Won't advance in power to revs

Posted: 23 Oct 2013, 09:23
by ghost123uk
Is this on Gas or Petrol ?

And not sure what you mean when you say "When you press the accelerator the engine noise dips but will not advance??" Give us a bit more to go on there ;)

Re: Won't advance in power to revs

Posted: 23 Oct 2013, 11:47
by itchyfeet
my guess is he means the engine 'note' lowers but revs don't increase

I used to get this when my Gas was too lean at revs, press the throttle and it didn't go any faster just the engine note changed.

So my guess is fuel starvation.

Re: Won't advance in power to revs

Posted: 23 Oct 2013, 11:49
by Ralf85
If this has happended out of the blue, check fuel filter(s). A blocked filter is one cause of a sudden loss of power.
:)

Re: Won't advance in power to revs

Posted: 23 Oct 2013, 11:59
by itchyfeet
^^^ if it's doing this on Petrol, question has been asked if it's doing this on Gas or Petrol (or both?)

Re: Won't advance in power to revs

Posted: 23 Oct 2013, 13:22
by 1_eyed_jim
Sorry for late reply. The problem is as you say the note of the engine lowers and eventually the revs pick up but there is no power. It's the same on gas or petrol. I've done a short video of me reving the van whilst it was running on petrol. Hope it helps. The engine cut out a few seconds after the video

http://youtu.be/qXmXp0hw6NY" onclick="window.open(this.href);return false;

Re: Won't advance in power to revs

Posted: 23 Oct 2013, 14:16
by kevtherev
hand brake on?
brakes binding?
weak mixture?
timing fault (no advance)

Re: Won't advance in power to revs

Posted: 23 Oct 2013, 14:41
by 1_eyed_jim
Thought it might be a vacuum fault? Not breaks as I coasted just fine. Guess I need to check the timing.

Re: Won't advance in power to revs

Posted: 23 Oct 2013, 16:53
by 1_eyed_jim
So been looking a bit more today but not really sure what im looking for. I removed the vac pipe from the carb side and removed the dizzy cap and sucked the vac pipe. A good hard suck moves things inside the dizzy and sealing it with my tongue it stays in that position. Does this mean the vacuum is ok? I had to really suck on this. Is this normal? The vacuum is there on the carb side too.

Can it be a timing issue as it happened all of a sudden?

Removed each ht lead whilst the engine is running and they are all sparking and having a effect on the engine speed when each one is removed. Does this mean it's firing ok? :? :?

Re: Won't advance in power to revs

Posted: 23 Oct 2013, 17:09
by itchyfeet
Sucking on the dizzy vac pipe as you did indicates that is working another check is pop the pipe off when idling andyou should hear the revs drop

Yes any fault can happen suddenly

Yes spark plug test sounds reasonable

If it happens on both gas and petrol then pointing at ignition

Have you got a timing gun? If so look at the timing some numbers here but you wil need to decide what engine

http://www.brick-yard.co.uk/VehicleSpec ... engine.htm" onclick="window.open(this.href);return false;

Your garage says 1.9 wbx dg dh etc : :lol: could you choose one?

Re: Won't advance in power to revs

Posted: 23 Oct 2013, 17:15
by pionte
Engine note changes due to more air being sacked in, sounds like fuel starvation to me, as suggested check both fuel filters, and the accelerator pump/jet. then vacuum side. Doesn't sound like a misfire from your description.

Re: Won't advance in power to revs

Posted: 23 Oct 2013, 17:19
by itchyfeet
pionte wrote:Engine note changes due to more air being sacked in, sounds like fuel starvation to me, as suggested check both fuel filters, and the accelerator pump/jet. then vacuum side. Doesn't sound like a misfire from your description.

Yes to me too but you would expect diferent results on lpg as to petrol and he's saying its the same
Lpg is very much more sensitive to air leaks than petrol it would have to be a major air leak to do that on petrol

Ok just watched the vid and its a dg

Re: Won't advance in power to revs

Posted: 23 Oct 2013, 17:20
by 1_eyed_jim
itchyfeet wrote:Sucking on the dizzy vac pipe as you did indicates that is working another check is pop the pipe off when idling andyou should hear the revs drop

Yes any fault can happen suddenly

Yes spark plug test sounds reasonable

If it happens on both gas and petrol then pointing at ignition

Have you got a timing gun? If so look at the timing some numbers here but you wil need to decide what engine

http://www.brick-yard.co.uk/VehicleSpec ... engine.htm" onclick="window.open(this.href);return false;

Your garage says 1.9 wbx dg dh etc : :lol: could you choose one?

Thanks. I will have to buy a timing light. Can you check without one?

It's a 1986 1.9 DG

Re: Won't advance in power to revs

Posted: 23 Oct 2013, 17:23
by 1_eyed_jim
pionte wrote:Engine note changes due to more air being sacked in, sounds like fuel starvation to me, as suggested check both fuel filters, and the accelerator pump/jet. then vacuum side. Doesn't sound like a misfire from your description.

The petrol doesn't get used much about once a month when I run out of LPG. I've removed the LPG filter again and I've found rust dust again. This is the second time this year is this normal??

Re: Won't advance in power to revs

Posted: 23 Oct 2013, 17:29
by itchyfeet
So idle is bad on petrol but have you given it a drive on petrol its not the same thing

if it drives better on petrol then points to air leaks