Page 1 of 1
High and pulsing idle fix
Posted: Sat Sep 24, 2005 2:26 pm
by RobF300
High, erratic idle.
Just got out and had a look, my 89 roza been running at 1200rpm and pulsing to 1400rpm once warmed up...
Turns out a vacuum tube had disconnected from the unit beneath the distributor... Just in case anyone is interested...
Posted: Sat Sep 24, 2005 11:53 pm
by murcod
One of the vacuum advance lines?
You can get similar symptoms from the air bypass valve in the throttle body jamming open too.
Posted: Sun Sep 25, 2005 8:30 am
by RobF300
yeah i read your post... i lied about it being fixed, i dont have the pulse anymore, but the idle is high (1100)...
Where is this valve you are talking about, you said you can see it with the air intake piping off, is it the hole in the center right sucking air in just before the butterfly?
Do you still have any pics too?
Cheers
Rob
Posted: Sun Sep 25, 2005 11:04 am
by murcod
Hmmm..... I had pics on here once.
It's an oval hole - the largest one from memory that's in front of the throttle butterfly. When the engine coolant is cold it should open fully and increase the idle. As the engine warms up it's supposed to fully close. There are two coolant hoses that run into it from underneath the throttle body.
Check the coolant is flowing through it first.
Mine jammed open and I used some WD40 type stuff and a screwdriver to free it up- don't use silicone spray as it will poison your oxy sensor!!
Posted: Mon Sep 26, 2005 8:26 pm
by murcod
A pic.
Red arrow pointing to hole. Throttle butterfly is held open in the pic BTW, the hole is in front of it when it's closed.