CIS Hose question

[mikester]

I have been having a problem with my CIS machine.

I've got this nipple on the side of my airbox that really looks like it should have a hose on it. the problem seems to be common - before it is warm (which doesn't take long) it runs poorly and backfires.

From what I understand I need to check the WUR and the Cold start switch?

I did the test where I move the throttle just to open with the engine off and I heard no click from this switch. Question is, where is the switch?

Pic attached - advice appreciated.



Thanks!

[mikester]

Brightened up the pic a bit...

[ubiquity0]

Airboxes have various plugs that stop off irrelevant openings that have been applicable for some years & not others. That hole is probably letting unfiltered air into your intake, so it'd be a good idea to find the rubber plug (pelican sells it). As its upstream of the sensor plate its not the cause of your poor running though.

[tsuter]

Oil tank breather hose connection. It may not be open to the inside. Mine was not... at least not when the breather hose used to go to the back of the bonnet. Now - no bonnet so it goes here.

[mikester]

Hmmm....where's the other end of that?

[Jdub]

Check your popoff valve and make sure the CO2 is set correctly before you spend any more time with the WUR, etc. Also try to get a fingernail under the screws that hold the airbox on to see if it has blown.

When you know your baseline is OK then move to the more complicated parts.

The cold start switch dumps gas directly into the intakes (at least on the '78/9). The car probably wouldn't start if that wasn't working. I'd work the easy stuff, gas filter, etc. before I went any further on the parts you are looking at.

The nipple on the airbox: can you put a finger directly into the airbox through it? Mine is blocked off.

Best of luck,
John

[sammyg2]

On my USA 1980 SC that nipple on the air box is plugged, or at least is was until I modified it for the turbo installation. Now it is hooked up to the oil tank but that is not the factory configuration.
Even if it is left open it will not affect the way the engine runs, it will only allow unfiltered air into the engine. Plug it off and look elsewhere for your problem.

[yelcab1]

Mine is plugged.

[mikester]

Ill check that it is plugged - I honestly didn't.

[David]

Sounds like you need a NEW WUR. If you're going to do your own CIS maintenance you really should buy a CIS pressure gauge. I think Drive Werks sells them for a little over $100.

[1fastredsc]

My 83 has the orfice plugged, it uses another opening for oil take breathing. I think your poor running cis has to do with the fuel injection somewhere. If your unsure of a leak in the cis system, you can always take a water spray bottle and spray around the area where you think there is a leak until you hear the motor stutter.