your IAC is dead. no longer opens below 150F. this causes rich idle, (lack of air)
the dash tacho gauge is not too accurate, (it's pure analog meter , takes spark pulses and turns that to meter volts, crudely.)
the first tach notch below 1 (1000) is 800. )200 per mark) (i use shop tachometers. that are dead accurate. to see what is really going on, )"measurement errors make a genius tech go down wrong path...."
when you start any 16v the iac is open, before the start, even at 70F, (70 is way below 150f) so is open a lot. cold and lets in air and idle races.... on all 16v.
a bad IAC is common failure , on 1990 cars. very common.. mine was stuck open. (screamed hot, unstoppable! till fixed.)
the 8v engine , the IAC can be seen with naked eye,,, not yours sadly but wait... we have that now. kinda(below).
but shows how it works , (same is yours) see this photo see that wax pellet activated cone valve.? and those gaps.. (i took reading with number drills to do that trick and is very revealing)
http://www.fixkick.com/fresh-air/Slide_S...age_9.html
40F is temperature of milk in the Refrigerator. (measured using accurate tools...) this gap sets cold idle speed on all G16s...
the 16v looks like next photo linked, and can only be tested in a pan of water, then blown into hole slots with lips. (open cold , closed hot, is all i can do)
the ECU when engine is cold,. assumes this valve works. if not?, engine EFI goes rich. (02 is not active cold so...)
![[Image: 16v_IAC_w1.jpg]](http://www.fixkick.com/fresh-air/Slide_Show/images/16v_IAC_w1.jpg)
the screws can be near impossible to remove (i had to do tricks to get them off.)
here is the last posters valve cut up.
![[Image: 3_09_11_15_11_58_34.jpeg]](http://www.fixkick.com/bbs2/Suzuki-bbs/gallery/3_09_11_15_11_58_34.jpeg)
to get a IAC< i had to buy used TBs ,one i found with whole intake manifold and TB and a working IAC, eureka !
the dash tacho gauge is not too accurate, (it's pure analog meter , takes spark pulses and turns that to meter volts, crudely.)
the first tach notch below 1 (1000) is 800. )200 per mark) (i use shop tachometers. that are dead accurate. to see what is really going on, )"measurement errors make a genius tech go down wrong path...."
when you start any 16v the iac is open, before the start, even at 70F, (70 is way below 150f) so is open a lot. cold and lets in air and idle races.... on all 16v.
a bad IAC is common failure , on 1990 cars. very common.. mine was stuck open. (screamed hot, unstoppable! till fixed.)
the 8v engine , the IAC can be seen with naked eye,,, not yours sadly but wait... we have that now. kinda(below).
but shows how it works , (same is yours) see this photo see that wax pellet activated cone valve.? and those gaps.. (i took reading with number drills to do that trick and is very revealing)
http://www.fixkick.com/fresh-air/Slide_S...age_9.html
40F is temperature of milk in the Refrigerator. (measured using accurate tools...) this gap sets cold idle speed on all G16s...
the 16v looks like next photo linked, and can only be tested in a pan of water, then blown into hole slots with lips. (open cold , closed hot, is all i can do)
the ECU when engine is cold,. assumes this valve works. if not?, engine EFI goes rich. (02 is not active cold so...)
the screws can be near impossible to remove (i had to do tricks to get them off.)
here is the last posters valve cut up.
to get a IAC< i had to buy used TBs ,one i found with whole intake manifold and TB and a working IAC, eureka !
http://www.fixkick.com