Blacktop - Lurches when coming off throttle

[Lanius]

Hey there, have had a look through previous threads, but can't find anything directly relating to the issue I've found with my AE111.

After lightly accelerating, when coming slightly off throttle, the car will lurch a bit. It accelerates fine, and doesn't lurch when coming onto throttle, only when coming off. It doesn't seem to be rev or gear dependent (although I've noticed it mostly in 3rd and 4th), and its quite intermittent.

From similar threads, I've seen throttle position sensors mentioned, or possibly worn / damaged engine mounts ... any other ideas?

TIA

[escortman]

yeh i was goin to say mounts

[RedMist]

Well I wasn't. I was going to say.... engine mounts.

[escortman]

o yeh check them 2

[rolla_fxgt]

O2 sensor? I assume blacktops run them

Sticking throttle cable?

[Bling]

when engine is cold or hot?

[~SlideWays~]

Our daily ST 20v has the exact same problem, so its obviously not going to be the AFM.

Ours has done it for years but as you say its intermitent, so after trying plugs, leads, coil pack, injector cleaner, cleanign AFM, etc I gave up lol.

Its definitely more common when cold.

I have noticed recently that it feels like the throttlebodies are sticking because its got a big flat spot when 1/2 throttle accelerating...then it audibly opens up like it comes unstuck. I think it may be dirty throttlebodies or something so I'm going to take it to bits to clean but is it possible that this is related?

What sort of behaviour would a stuffed oxygen sensors cause?

[RS13]

My ST does it too, its' fairly intermittent, although worst when it's cold.

[rolla_fxgt]

Our daily ST 20v has the exact same problem, so its obviously not going to be the AFM.

Ours has done it for years but as you say its intermitent, so after trying plugs, leads, coil pack, injector cleaner, cleanign AFM, etc I gave up lol.

Its definitely more common when cold.

I have noticed recently that it feels like the throttlebodies are sticking because its got a big flat spot when 1/2 throttle accelerating...then it audibly opens up like it comes unstuck. I think it may be dirty throttlebodies or something so I'm going to take it to bits to clean but is it possible that this is related?

What sort of behaviour would a stuffed oxygen sensors cause?

The idea of cleaning the throttle bodies makes sense to me, might be the project for the next fine weekend.

Yeah my silvertop loves to do it when cold, far less noticeable in Summer now I think about it.

When cold mine also drops well below 1000rpm when you just touch the throttle, and i mean the absolutly lightest touch, a heavier touch & its fine. Would this make more sense in deciding what it is that up? Does anyone elses do this?

[RS13]

Our daily ST 20v has the exact same problem, so its obviously not going to be the AFM.

Ours has done it for years but as you say its intermitent, so after trying plugs, leads, coil pack, injector cleaner, cleanign AFM, etc I gave up lol.

Its definitely more common when cold.

I have noticed recently that it feels like the throttlebodies are sticking because its got a big flat spot when 1/2 throttle accelerating...then it audibly opens up like it comes unstuck. I think it may be dirty throttlebodies or something so I'm going to take it to bits to clean but is it possible that this is related?

What sort of behaviour would a stuffed oxygen sensors cause?

The idea of cleaning the throttle bodies makes sense to me, might be the project for the next fine weekend.

Yeah my silvertop loves to do it when cold, far less noticeable in Summer now I think about it.

When cold mine also drops well below 1000rpm when you just touch the throttle, and i mean the absolutly lightest touch, a heavier touch & its fine. Would this make more sense in deciding what it is that up? Does anyone elses do this?

You mean it kinda hesitates briefly before you put your foot down? Mine does this, but again mostly when cold. I do need to replace my thermostat however, as it never gets past about 1/4 up the gauge unless I've been sitting in traffic for a while. Perhaps that has something to do with it? My 16V used to do it badly, however I found that it was due to a minor vacuum leak at the throttle body.

[rolla_fxgt]

Our daily ST 20v has the exact same problem, so its obviously not going to be the AFM.

Ours has done it for years but as you say its intermitent, so after trying plugs, leads, coil pack, injector cleaner, cleanign AFM, etc I gave up lol.

Its definitely more common when cold.

I have noticed recently that it feels like the throttlebodies are sticking because its got a big flat spot when 1/2 throttle accelerating...then it audibly opens up like it comes unstuck. I think it may be dirty throttlebodies or something so I'm going to take it to bits to clean but is it possible that this is related?

What sort of behaviour would a stuffed oxygen sensors cause?

The idea of cleaning the throttle bodies makes sense to me, might be the project for the next fine weekend.

Yeah my silvertop loves to do it when cold, far less noticeable in Summer now I think about it.

When cold mine also drops well below 1000rpm when you just touch the throttle, and i mean the absolutly lightest touch, a heavier touch & its fine. Would this make more sense in deciding what it is that up? Does anyone elses do this?

You mean it kinda hesitates briefly before you put your foot down? Mine does this, but again mostly when cold. I do need to replace my thermostat however, as it never gets past about 1/4 up the gauge unless I've been sitting in traffic for a while. Perhaps that has something to do with it? My 16V used to do it badly, however I found that it was due to a minor vacuum leak at the throttle body.

Exactly that.

I don't think mine is a thermostat issue, its normally around halfway, though sometimes does drop to about 1/4 on the downhill.

[Mr Revhead]

mine used to do it
clean the ITBs
fit a oil catch can that DOESNT feed back in, connect BOTH breathers to it.
make sure coil, plugs and leads are good.
i never got rid of it 1005 but the catch can helped a LOT