IAC valve

code p0420
code p0102
code po171
code p0113
I'm replacing the intake with cold air k/n, cause it looks shady
i might replace the iac valve tomorrow but i dont even know if it is broken
is there an easy test i can do for the iac?

Are you suggesting that you are getting this codes currently with the stock air intake? Are you curious what these codes are? What model year and engine does your LS have?

P0102 - Mass Air Flow (MAF) Circuit Low Input
P0113 - Intake Air Temperature (IAT) Circuit High Input
P0171 - System too Lean (Bank 1)
P0420 - EGR Flow Excessive Detected

I'd suggest that you try to remedy the source of these issues BEFORE swapping out the air intake. Many of these codes could be related to the install of the air intake, and it may be good to understand them before adding one more variable into the equation.

As for a test for the IAC, try turning on the A/C with the engine at idle, assuming your compressor engages. If, when the compressor clutch engages, the engine speed does not drop noticeably, the IAC is probably doing its job. You could also turn the steering all the way to one of the locks for a second or two. If when you reach lock, the engine speed doesn't drop noticeably, that's test 2 indicating the IAC is doing its job.

-Rod

Are you suggesting that you are getting this codes currently with the stock air intake? Are you curious what these codes are? What model year and engine does your LS have?

P0102 - Mass Air Flow (MAF) Circuit Low Input
P0113 - Intake Air Temperature (IAT) Circuit High Input
P0171 - System too Lean (Bank 1)
P0420 - EGR Flow Excessive Detected

I'd suggest that you try to remedy the source of these issues BEFORE swapping out the air intake. Many of these codes could be related to the install of the air intake, and it may be good to understand them before adding one more variable into the equation.

As for a test for the IAC, try turning on the A/C with the engine at idle, assuming your compressor engages. If, when the compressor clutch engages, the engine speed does not drop noticeably, the IAC is probably doing its job. You could also turn the steering all the way to one of the locks for a second or two. If when you reach lock, the engine speed doesn't drop noticeably, that's test 2 indicating the IAC is doing its job.

-Rodi replaced the iac valve with the stock intake. still wants to stall...everybody says it was the iac. now i just spent 112 bucks for nuttin. maybe undoing the battery then reconnecting will reset everything... i dunno if thats how it works though

Did you try any of the things I suggested in post #2 before replacing the IAC valve?

-Rod

Did you try any of the things I suggested in post #2 before replacing the IAC valve?

-Rodno i didnt but its still doin the same thing

Right, the suggestions in post #2 may have saved you $112 if you had tried them.

Water under the bridge. I'll take a peek at the troubleshooting charts for the 4 codes and see if there are some similarities between them. Or, if you would like me to send PDFs of the charts to you, send me a private message with an e-mail address for you that can accept PDF attachments.

-Rod

Right, the suggestions in post #2 may have saved you $112 if you had tried them.

Water under the bridge. I'll take a peek at the troubleshooting charts for the 4 codes and see if there are some similarities between them. Or, if you would like me to send PDFs of the charts to you, send me a private message with an e-mail address for you that can accept PDF attachments.

-Rodyes u r rite. those suggestions may have saved me money...real quik i tried the ac test no major difference in idle change when compressor engaged. but in park i turned the wheel rite or left a lil the rpms dropped considerably low even before i put the new iac in. but at lock it seemed fairly ok. i have www.lumberjak1984@yahoo.com