I have a little Kangaroo under the bonnet

Hi all. Its a 1993 defender 90. 200tdi

When im going up a moderate hill, in 2nd gear at 20mph the throttle seems to start to kangaroo jump up the road. only does it at 20mph in 2nd, and at 30mph in 3rd. I don't have enough power to go up the hill at 40mph in 4th. lol.

It feels to me like the governor overcompensates, causes a surge, then backs off a little too much, then overcompensates ect ect ect

this is as close a description I can give of the symptoms if anyone can relate?

thanks

This sort of thing is usually fuel starvation. If it idles for a while does it seem to have more power temporarily and then it drops off again?

Could be a blockage in the fuel pipes or filter, lift pump failing (most likely) or something else like an injector pump issue or injectors (very unlikely).

TBH I haven't noticed it being down on power at all....Ive thought it goes quite well considering I have 33" tyres on. Hauled an old disco to scrap yard Saturday and seemed to tow it well.

Its currently on 162k, previous owner claims it was serviced at 160k. I suppose a new lift pump and filters cant hurt

Try changing your fuel filter first.

Start with the cheap, simple stuff and then we can take things from there.

pbuf said:

TBH I haven't noticed it being down on power at all....Ive thought it goes quite well considering I have 33" tyres on.

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So if it's not down on power, it seems OK on the flat but not on hills? I don't fully understand...

But saying that my old 300Tdi Discovery seemed OK on the flat but get to a little incline and it was just terrible. I couldn't even reverse out of my own drive and it must be a 50cm rise over about 3 meters. This turned out to be a combination of blocked fuel line, knackered lift pump and an old breathing engine. It finally manifested itself by only being able to tickover and if you tried to drive it would just lose all power. Fixed the blockage and the lift pump and it was better, but you can't polish a turd!

tetsu0san said:

So if it's not down on power, it seems OK on the flat but not on hills? I don't fully understand...

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It doesnt seem to be down on power, its just on a certain steep hill if you cruise up there at a constant 20mph in 2nd or 30 in 3rd (not with foot to floor) it creates this wierd little power on off on off on off surge

Check those little pipes that link turbo and fuel pump.

tottot said:

Check those little pipes that link turbo and fuel pump.

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Got the day off Tuesday so will get straight on it

Got round to fitting the new bearmach lift pump on saturday, problem is still evident

Is your fuel return line from the injectors blocked?

pbuf said:

Hi all. Its a 1993 defender 90. 200tdi

When im going up a moderate hill, in 2nd gear at 20mph the throttle seems to start to kangaroo jump up the road. only does it at 20mph in 2nd, and at 30mph in 3rd. I don't have enough power to go up the hill at 40mph in 4th. lol.

It feels to me like the governor overcompensates, causes a surge, then backs off a little too much, then overcompensates ect ect ect

this is as close a description I can give of the symptoms if anyone can relate?

thanks

Click to expand...

From the speeds you give me and the gears it seems like it's doing it at about 2000rpm.

Is it be OK above this rev range? Or is it 2000rpm and above?

Sounds like fuel starvation to me, please tell me you changed the fuel filter first and it didn't do anything hence the lift pump? Fuel filters are not always considered standard service items - depends on what level of service it go - usually people wrongly say service meaning oil and oil filter.

Oldseadog said:

Is your fuel return line from the injectors blocked?

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How would i tell? Airline in the pipe to the tank?

discomania said:

From the speeds you give me and the gears it seems like it's doing it at about 2000rpm.

Is it be OK above this rev range? Or is it 2000rpm and above?

Sounds like fuel starvation to me, please tell me you changed the fuel filter first and it didn't do anything hence the lift pump? Fuel filters are not always considered standard service items - depends on what level of service it go - usually people wrongly say service meaning oil and oil filter.

Click to expand...

It seems to do it just at this speed. Exactly 20mph on 2nd and 30mph in 3rd. And only on a decent pitch of a hill. i havent done filters yet, i must get some.

pbuf said:

How would i tell? Airline in the pipe to the tank?

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Remove each of the banjo bolts and blow through, and then blow through to the tank.

Do not use a high pressure air line!!