Rising tickover on '94 1100

[MMC]

This one's got me foxed...

OK, so that's nothing unusual, but my 1100 starts up and ticks over from cold just fine. Sits at 1,200rpm quite cheerfully cold. But as it gets warmer, the tickover revs rise to around 2,000rpm.

It's just started happening... Can't find anything on here about the problem or on the web.

Anyone got any ideas what's causing it and how to cure it?

 

[(RIP) Kaister]

air leak - caused by split inlet rubbers ?

or the slack has gone out of one of the throttle cables

or - leftfield - the oxygen sensor is playing up in the exhaust and telling the ecu it needs more fuel.


is the problem common to colder damper weather ?

 

[MMC]

air leak - caused by split inlet rubbers ?

or the slack has gone out of one of the throttle cables

or - leftfield - the oxygen sensor is playing up in the exhaust and telling the ecu it needs more fuel.


is the problem common to cold weather ?

Ta for those - I'll investigate further...

Would slack in one throttle cable give it a rough tickover - along the lines of the famous "cable ferrule sitting on top of the adjuster" problem?

 

[(RIP) Kaister]

Ta for those - I'll investigate further...

Would slack in one throttle cable give it a rough tickover - along the lines of the famous "cable ferrule sitting on top of the adjuster" problem?

yep - but not as bad - it'd only be out slightly and could be the cable or the stop adjuster holding the butterfly open a gnat's cock more than it should be.

of course - you needyour own home made manometer and check the brass airscrew balance at the same time

 

[MMC]

yep - but not as bad - it'd only be out slightly and could be the cable or the stop adjuster holding the butterfly open a gnat's cock more than it should be.

of course - you needyour own home made manometer and check the brass airscrew balance at the same time

Ah, yes - I'll just dig my manometer out of the manometer cupboard under the stairs... Actually, I've got a Carbtune in the shed.

Why does it bump the warm tickover up then?

 

[(RIP) Kaister]

probably cos its slightly too rich anyway - a bit more air and its away.

thats why all the settings have to work in harmony together at the same time consecutively.

 

[DrFarkoff]

Check yer rubber diddies are on at the vac take off points they perish as fall off so lettin in more air basically the same idea as when you open the butterflies, with the fast idle control when it's cold to let extra air in for the over rich when cold fuel settings!

Also try spraying WD or preferably a non rubber attacking lubricant around the head to throttle body rubbers they just start going funny shapes and cause air leaks!

 

[MMC]

Check yer rubber diddies are on at the vac take off points they perish as fall off so lettin in more air basically the same idea as when you open the butterflies, with the fast idle control when it's cold to let extra air in for the over rich when cold fuel settings!

Also try spraying WD or preferably a non rubber attacking lubricant around the head to throttle body rubbers they just start going funny shapes and cause air leaks!

Cheers Jaythro - I'll give it a go.