So, many of you probably comes across idle problems with the KA engines. I have bought both
89 AND 90 KA engines to show the difference in IDLE systems (also known as IACV, AAC etc..)
Since I did rebuilt the motor head to toe, everything gets kind of messed up, and i dont know
which one is for what motor, but thats not the issue.
IF you have the idle problem, you might tend to go to the IAC, but not sure which one is bad.
This is why I made up a report on what I find very interesting about the IAC system.
PS: IAC is VERY important if you have auto start, because winter in chicago doesn't help. lol.
EVERY PIC IS ON ITS RESPECTIVE SIDE.!!!!
Here is the picture of two VERY similar IACV from a KA24E (not sure which of what is what year)
As you can see, the IAC housing bolt pattern is exactly the same. Both of them will bolt up to
the intake manifold housing. BUT the IAC itself is a different design.
This is the picture of the IAC itself. One is obviously shorter than the other... Not only that, the "pintle" design is also different.
This is the difference in the IACV housing again in super close up picture. As you can see, the one on the right has a spring loaded extra pintle which is then actuated by the OTHER small pintle on the IAC itself (refer back to previous pic) As the one on the left is empty, because the IAC for it has its own "pintle housing" you can say, and the pintle moves in the housing.
This is the IAC housing difference again, as I said before the IAC housing on the left is hollow,
while the one on the right has its own spring loaded pintle built in.
Another side picture dfference.
Swapping IAC in its entirity is very easy, 4 10mm bolts and bottom rubber hose that goes to the breather. NO you cannot just swap the AAC by itself unless you have the same exact part,
If you end up in my position, just swap the whole IAC, and it will 100% work. tried...
This difference in design is between the KA24E 1989 motor and 1990.
Hope this helps some 240 die hard fans out there. My first writeup. Hope this really help other people.