Fuel Starvation

[Vimeous]

My gf has an '87 Toyota Celica 2.0GT 16v and a mighty fine motor it is too. However we're having one or two issues, one specifically mechanical. Does the following describe the symptoms of fuel starvation or something else?:

1. Idles fine.
2. Full throttle is smooth as it should be.
3. The smaller the throttle opening the more juddery it gets to the point where at modest, everyday traffic openings it bunnyhops dramatically.

If I'm right about the fuel starvation is it likely to be ECU related or something more simple and mechanical a part swap or two will fix?

Oh and it's the same on any currently available fuel including Optimax.

Please help!

[Lowe]

Hmm, not too sure. If it was a fuel issue then under full throttle it would be just as noticeable surely. So it's not a filter/blockage problem...

Is it when you're pulling away or just driving along?

[Vimeous]

Both.
Seems to occur mostly below 2000rpm.
Could it be a change-over point in the ECU from one fueling setting to another?

[Tumble]

maybe it's the other way round - too much fuel going in... at full throttle, the engine's asking for all the fuel it can get, and it's burning it fast enough to be able to run a little rich... idling and the throttle's gonna be closed... if there's too much going into the motor at a small throttle opening it could just flood and bog a bit. If it happens more when it's cold it could be that the automatice choke is playing silly beggars....

[Lowe]

If that was the case Tumble, it'd be idling high...

/ponders

[5lab]

sounds like an air leak of some kind..

[Vimeous]

Idling normal 650-700-rpm.
Happens hot and cold.
I thought at wide throttle openings you supply more fuel and air to provide a larger bang. Smaller throttle openings = less fuel and air? If there is intermittant fuel pressure for a given opening then there may be occasions when there's nothing to burn, hence the on-off nature of the bunny hop.
At least that was my guess but I don't know enough to realise if that's the only option.

5lab can you expand a little please? Not enough air and the fuel is intermittantly flooding?