Addz

My brothers RS has had more of its fair share of problems, and we have been trying to sort them all out. Replaced the fan switch (so the fan worked as it should, not on all the time) and also sorted out the dodgy fuel pump wiring that the previous owner bodged!

Went to start it up and it fired fine, but it was idling way too high. I adjusted the screw underneath the inlet manifold so it was idling around 1000rpm.

Went for a drive, and about 2 mins after we went off, my brother said that the idling had dropped right down, to like 500rpm. Pulled over, and I adjusted the screw back so it was up to 1000 rpm.

Went for a 10min drive and all was well.

Then just as we were approaching home, it was clear that at idle it had shot back up to well over 2000rpm.

Limped back home, and again i adjusted it so it went back down to 1000rpm.

But then as it was just sitting there idling on the driveway, the revs dropped down to like 400rpm

Any idea as to whats causing all this bizaare idling?

vroooom ptssssh

aux air device (idle speed control valve) see here:

https://passionford.com/forum/viewtopic.php?t=123508

bzd32

hi Addz

i take it the car runs down the road ok, its just the idling

its poss you have an air leak in the beather system eg oil filler cap, dip stick or breather piping. just check them first make sure there ok because the car will not idle right if there not sealed.

if ok please let me know (start off cheap and simple first)

Addz

Mate, the thing i was adjusting was:



Whats the plug the red arrow is pointing at? And is the yellow arrow what you on about?

vroooom ptssssh

Addz, as bzd32 sais check all the breather options, dip stick, oil cap, rocker cover gasket could be leaking and check/clean the breather (left hand side of rocker cover-inlet as u face the engine). the engine should stall if you take the oil cap off. . or if u lift it slightly it shuld suck the cap back on!

the first pic that is the idle speed adjustment screw.

the 2nd pic im not sure what the plug is for but its plugged onto the aux air device (alternatively named but fundamentaly it is an idle speed control valve) and the yellow arrow is a hose connecting to the other part of the aux air device!

read that thread on how to check and clean the aux air device after youve checked the breather system firstly.

Addz

Right, I think ill clean it anyways. Is it OK to use Carb Cleaner to clean it, and some WD40 to lube it up?

Ill check for air leaks and keep you lot posted.

Spraying Carb cleaner around the hose joins should reveal any leaks shouldnt it?

vroooom ptssssh

Addz, carb cleaner and WD40 is fine to clean it with, but do it with the hoses off the valve. also as said on that other post, check the wires to it/clean the plug and clean the earth andmakesure the earth is secure.

wd40 on all the vacuum/boost hose joints will reveal any leaks yes, idle should pick up if there is a leak.