Another Idle Problem.

[roccorich 16]

I have read a load of threads on peoples idle problems but none seem to match my problem.

 

Basically the car idles high. Yet if i blip the throttle it will drop to 1000 then rises to 2000 again.

 

Sometimes it will stay at 1000...

 

I have spent the evening cleaning the throttle body and removing the brown plug.

The throttle body was not very dirty but there was a fair bit of oil in the manifold.

 

I checked that the switch on the throttle body clicks when the throttle closes and the throttle is definatly closing.

 

My next step was going to be looking at the SAD and checking all the things the Haynes book details with the rest of the injection stuff.

 

Where does the SAD connect to.

 

I thought it was onto the bottom of the throttle body but I just have two coolant connections and a vacuume line to the dizzy.

 

Cheers

 

Rich

[Slo 283 1 Cars]

The sad goes to the very bottom of the inlet manifold in front of the starter and to the air pipe before the throttle body.

 

Main cause of your problem is usually either one of these 2 pipes perishing Or any other air pipe perishing come to think of it or the bolt that holds the oil filler neck onto the inlet manifold leaking air in past the threads if its not tight.

 

Of course it could be a number of other things to, one things for sure poor maintenance is a big contributor.

 

Check the throttle butterfly spindle for leaks too with some wd40 and the engine running to see if it slows the idle down.

[pugdamo 111 2 Cars]

Quick check would be clamp the pipe from the inlet to the SAD when the engine is at normal operating temp,if it idles properly check the SAD and its pipework

[welshpug 1,661]

Switch may click, but does it conduct?

[roccorich 16]

Im gonna check it all with a multimeter next, by the time i'd got the throttle clean and finished soldering out the brown plug it was gone 10.

 

Ill find the SAD and have a look. So the one to clamp is the one on the outside of the 90 degree bend before the throttle body?

 

So am I right in thinking the air comes out through that pipe through the SAD and into the manifold?

 

cheers

 

Rich

[welshpug 1,661]

yup.

[roccorich 16]

Cool.

 

Im a bit dubious of it being an airleak as it drops when I rev it before creeping up again???

[roccorich 16]

Cheers Slo.

 

You were right about the oil filler mount.

 

I didnt realise the screwhole went all the way through!!!

 

So i hadnt actually reattatched it since I moved it to change the starter motor.

 

When I started the car first time after the starter chsnge it was idling to low so i wound the idle screw put and it shot up

 

The temporary drop after blipping the revs must have been becsuse the throttle switch was richening the mixture for a few seconds.

 

Well I look stupid now but I hope someone else can learn from this.

 

Cheers for the help guys

[Anthony 1,003]

You're not the first and you won't be the last, don't worry!