AAR is OK, but no 1500rpms at cold start

cary · 02-05-2004, 09:52 AM

Just tinkering on the 2.0 while it rests for the winter.
I'm going to swap this into my project car when its done.

But I can't seem to get an increased idle at cold start. AAR checks out ok. Vacuum on the inlet when cold. But doesn't seem to raise it much above 900 rpms. If I pull the outlet off the AAR, where its getting all the air it can take. I can get it up to 1200 rpms.
Seems to me that should be much higher.

In Brads info he mentioned that he was working on a fix for this.
Did he come up an answer ? Higher reading TS2 ?

Plus I copied my notes a year or so ago. Has there been changes, and should I copy off a new set.

Bleyseng · Bleyseng's Garage

First, check all the timing so its at 27degrees BTDC at 3500rpms.
Check the hoses, is the vacuum hose from the AAR valve plugged into the aircleaner?
Try unplugging the other hose from the AAR valve, if the rpms go up to 1800 then the AAR is stuck partway open.

The AAR is just a big vacuum leak to add air and raise the rpms when cold.
Geoff

scotty914 · 02-06-2004, 10:54 AM

also when the motor is very cold 900 rpms is all the motor maybe able to do till it warms some more. after a min or so does it rise to 1000 rpm then the aar starts closing and slowing back down. one other thing is makes sure it closes all the way you might have the idle adjusted to handle the aar slightly open.

M. Hendrix · 02-06-2004, 06:33 PM

The car I bought from Otto's was tuned with the AAR failed open.

Get the car warm (drive it 30 minutes) plug the AAR hose that sucks (from the airbox) and adjust idle to 950-1000, then unplug the hose, and reconnect it.

If the idle is UP profoundly, disco the AAR again.

Next time you start the car cold, you either have 1600-1800 idle, or a dead AAR.

M

cary · 04-01-2004, 11:53 AM

Another Kudo for Brad.

Dwell was way off. Like reading 63 degrees. Put it back to 44 degrees.
Starts much better. Not 1500. But will it start and run without having to throttle it up.
So I'll make sure the AAR is opening all the way. Then maybe a higher CHT sender. If I remember this one reads a little low when cold. Like 1500 ohms.