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Daubrey
07-07-2013, 09:35 PM
I have searched the site for answers to these question to no avail: Where is the IAC located on the LT1 engine (a picture would be great) and how exactly do you perform the paperclip test to read the codes on a 95 PS190?

wtrskr
07-07-2013, 11:37 PM
Regarding reading the codes, check my post on the 96 TBI black smoke thread. Double check this, but since they are both GM engines I'm assuming the TBI and the LT1 engine have the same code system. You have to find the connector that has little letters on each side marking the terminals (A-I). You may need a flashlight.

If you do some googling you can find the proper terminals for inserting the paperclip (A and B) and what the different codes mean. The engine light does a series of flashes to relay the numbers. If it just flashes the same thing over and over (number 12), then everything is okay.

Not sure about where the IAC is on the LT1.

JimN
07-08-2013, 12:19 AM
I have searched the site for answers to these question to no avail: Where is the IAC located on the LT1 engine (a picture would be great) and how exactly do you perform the paperclip test to read the codes on a 95 PS190?

Look for a part that looks like the one in the link-
http://www.ecklerscorvette.com/corvette-idle-air-control-valve-lt1-or-lt4-1995-1996.html

I sent a PM with the details for using the paper clip. If you have a simple code scanner, you can use that, instead.

kpickett
07-08-2013, 01:37 AM
Hey Jim,
Could you please PM me the details on the paper clip code test, too? I would really appreciate it. Also, I posted a new thread that I'm hoping you might weigh in on. I always appreciate your advice. Thanks,
Kyle

Table Rocker
07-08-2013, 02:57 PM
Regarding reading the codes, check my post on the 96 TBI black smoke thread. Double check this, but since they are both GM engines I'm assuming the TBI and the LT1 engine have the same code system. You have to find the connector that has little letters on each side marking the terminals (A-I). You may need a flashlight.

If you do some googling you can find the proper terminals for inserting the paperclip (A and B) and what the different codes mean. The engine light does a series of flashes to relay the numbers. If it just flashes the same thing over and over (number 12), then everything is okay.

Not sure about where the IAC is on the LT1.
It is located on the bottom of the throttle body, as in this pic from a Z28:
http://www.shbox.com/1/iac3.jpg
http://www.shbox.com/1/iac3.jpg (http://www.shbox.com/1/iac3.jpg)

Also, I believe you have to adjust the IAC position after you change it out so it knows where it is. I found this, but I have no idea if this is how it is done on our boats:
Depress accelerator slightly
Start engine, then release accelerator pedal, run engine for 5 seconds
Turn ignition "OFF" for ten seconds
Restart engine and check for proper idle operation
It is NOT recommended to to push or pull on the pintle of an IAC that has been in service. The force required can damage the threads on the worm drive. Also, do not soak the IAC in any liquid cleaner or solvent, as damage may result. When installing a new IAC, you may move the pintle to match the measurement of the old one. The force required to move a NEW valve will not cause damage to it. Use engine oil to lubricate the o-ring. Tighten attaching screws to 27 lb. in.

http://shbox.com/1/4th_gen_tech2.html

towelshoot
07-08-2013, 05:35 PM
I picked one up at Advance for $33. It was a BWD part number 21755. I worked perfect. I just installed it and did nothing else.