Full throttle power loss on Auto 2.1

[Dyno]

Hi chaps,

I have a 88 2.1 Auto caravelle and it runs beautifully.... however I was driving it between junction 26 to 22 on the M62 yesterday and noted on the big hill up the motorway the Van was losing speed. Thats obviously normal as the van is brick shaped (wind tunnel tested). I had one passenger and not any other loads.

I was doing 70mph at 3800 rpms up hill and the van slowed to about 60mph on the biggest hill. I slowly put my foot down to the floor to see if the bus would perform. I experienced a power loss at full throttle. The van slowed to 35mph in the end lugging up the hill. It didn't down shift to 2nd like i thought it would. I manually shifted it down and the revs rose and the bus took off again. however the van was losing power when shifting in to drive and up shifting to 3rd by itself.

This is the weired thing...

When doing the exact same journey again I kept the throttle at 3/4 open! and the bus cruised it happily up a steep hill in wind at 65mph. This is what I expected.

When I used the full throttle full open the bus again suddenly lost power and struggled again.. I can repeat this experiment every time. I recently changed the ATF with 3 litres of fresh fluid.


1. Why is my van doing this only at full throttle?
2. Should it have down shifted by itself?
3. Do these boxes have a kickdown? The Haynes manual doesn't cover it.

Any help appreciated. Its a brilliant bus apart from this strange issue.

[ermie571]

I have a carbed 2.1, manual

exactly the same.....at full throttle get quicker power loss than at 3/4....or the sweet point as I call it....

I get round it by coming off the pedal, letting it slow a little then re-applying at 3/4 - if I do this as I notice the power loss, it generally corrects itself. I don't very often drive at full throttle cos it just doesn't like it. Brief spurt to get round something, but that is it.

learn its quirks, and drive with attention to them

Em
xx

[toomanytoys]

Sounds very much like fuel starvation in both cases.. either furel pump is not keeping up, filter blocked, of on the injected engine the fuel pressure regulator is faulty...

In either case, if it is starvation then you WILL cause engine damage.. get it checked out asap...

Em, is this on gas or on petrol? or both?

[Dyno]

Hi chaps,

Thanks for the comments..

Well first off I have adjusted the throttle cable correctly from the engine and under the pedal. This now means the Bus is much more responsive and drives around brilliantly.

I tried the hill again (its a huge long climb) and the bus was going well. The kick down activated and the bus held 47mph at 4000 rpms, which shows how steep the bloody hill is. Its the UK's highest highway apparently.

Still the bus struggled and it got very hot indeed.

I drove some other parts of the M1 from J42 to J37 to Barnsley and tackled some other hills and they were 60mph steady climbs with good temps and no drama.


I don't remember my last auto t3 2.1 driving like this. I am sure it had more miles and was torquey... still I didn't tackle hills like this.

I think I need more bhp... Subaruuu where are you! Shame I haven't got 2.5k to spend on the bus.

[Dyno]

Sounds very much like fuel starvation in both cases.. either furel pump is not keeping up, filter blocked, of on the injected engine the fuel pressure regulator is faulty...

In either case, if it is starvation then you WILL cause engine damage.. get it checked out asap...

Em, is this on gas or on petrol? or both?

This still could be an issue... The fuel filter is new. I will have to find out how to test the pump and then regulator to ensure this is not the case. I'll ask my garage.



Incidently for others reading this thread; I am using a great garage based in Bradford called S-Line Motors. Sid who owns the garage has recommissioned my Bus. He specialises in VAG and BMW/Merc basically german cars but works on Jags and all sorts. He runs and also owns a fantastic 2.1 Caravelle 5 speeder. He is very reasonable and very helpful.

S-Line Motors: 07971728333
Bradford

[ermie571]

Sounds very much like fuel starvation in both cases.. either furel pump is not keeping up, filter blocked, of on the injected engine the fuel pressure regulator is faulty...

In either case, if it is starvation then you WILL cause engine damage.. get it checked out asap...

Em, is this on gas or on petrol? or both?

OOO Si - now I have sommat else to worry about. I guess its on gas, cos I don't drive on petrol!!!! And it only happens sometimes.

I don't drive it at 70 for long on the flat.....cos I don't want to thrash the engine either. Happy to keep it at 60-65.

I'm thinking that it is most likely me getting the wrong gearing....and rather than slowing and changing down.....thus increasing revs and torque....I just press the accelerator.

Em
xx

[getunder]

See my post on fuel filter. New filter or not my new filter blocked due to material lodging in the nylon pipe where it enters the filter chamber itself , there seems to be a moulding mark or tiny, tiny flange there. Could happen the same day as fitting a new filter due to disturbance.