Juddery at Speed

[WonkyGibbon]

Not been my day today.

The engine was massively juddery this morning on the motorway, cutting in and out, often more out than in. It only seems to really do it at speed - it was okay on the A roads. I filled the car last night, so dirty fuel could be an issue (I['ve had this before) - but this was from a Shell that I've used for years and I've not had a duff tank from them before. And it wouldn't explain why it was okay at idle.

Could it be fuel filter related - partially clogged or something ?

Thanks in advance for your help,

WG

[spivvy]

could be air flow meters may be worth giving them a clean

[Harry1972M]

I agree with Spivvy re AFM's I had this about 2 years ago and ended up with replacements which solved the problem - you can disconnect them and run the car breifly to see if it is better but you must only disconnect one at a time.

[WonkyGibbon]

Thanks guys.

Very confusing. On my trip out this morning - I ended up disconnecting the throttle pot to put it into "limp home" mode. It conbtinued in suitably juddery knackered mode.

However - on the return trip home it behaved perfectly. Very annoying 'cos it makes it so hard to work out what's going on. The only thing I can thing that was different was that the ambient temperature was rather lower this evening - overcast and cool - whereas this morning it was pretty darned hot.

Thanks for all your thoughts - wish the damn thing was consistent !

WG

[Harry1972M]

Sounds familiar from a couple of years back - if it still stuttered without the TP connected then you can more or less rule this out - Re the AFMs mine used to behave perfect until the slightest hint of dampness in the air and then cough splutter judder !!!

[ketvrin]

I take it you have checked for bad plugs and leads or connections ? How is your distributor cap and is the rotor arm clean ? maybe electrical not fuel ?

K

[WonkyGibbon]

ketvrin said:

I take it you have checked for bad plugs and leads or connections ? How is your distributor cap and is the rotor arm clean ? maybe electrical not fuel ?

K

That's a good point - I'll have a look. Thanks !

[bil]

Have just been through whats sounds like a similar experience, car fine at low speed but get to motorway speed and juddering would commence, backing off then didnt help. Having played with most of the electrics found that one of the middle cylinder leads was working loose, thus creating poor connection and misfiring. Have sent for new leads to replace, will now more after the change.
Bil