Hello everyone.
Just a weird question about the IAC valve, diode and Ohms and not too sure how to explain it.
I have a 87 GT vert. There is a diode in-line going to the IAC.. I've read that all remanufactured IAC valves today now come with a diode built in.
I've read that you are not suppose to have both in-line and IAC valve diodes working at the same time or you will have surging - hunting - hanging idle.
To find out if your IAC has it built in, there should be a "D" on the plastic connector on the IAC or use a DVM on ohms and probe the IAC tabs. One direction should read 7-13ohms and the other way should be infinity.
Everywhere I read, everyone says:
IAC should have 7-13ohms, if not then replace.
IAC should have a "D" on the plastic connector to have a built in diode
86-88's IACs came with non built-in diodes. The diodes are the wiring in front of the plug
89-93 IACs came with built-in diodes.
If your IAC valve has a built in diode, you need to remove the diode that is in-line right before the plug.
sounds straightforward.
What is so confusing me is, I've tested the IAC that was on the car. There was a "3D" on the IAC connector so it should have the diode built in but when I check the ohms, it reads 5.3 ohms both ways!
so I purchased a new one the other day from Rock Auto - brand Standard motor products. After receiving it, I looked for the "D". This one didn't have any markings and also ohm'd out to 5.3 both ways.
so I purchased the best possible part from Rock Auto - brand Motorcraft CX1824 knowing this is original Ford. I received it today and there is a "4D" on it but again when I ohm it, it's 5.3 both ways.
I even contacted Standard motor products customer service to see if they are actually built with the diode even though there isn't a "D" on it and they confirmed yes there is a diode.
I'm completely stumped here why they are not 7-13 ohms and don't want to remove the inline Diode if these now (3) IACs don't have them built in.
Funny thing is all 1986 to 1993 IAC valves, today, all are the same PART#'s
So that tells me an IAC for a 1987 and one for a 1991 must all come with a diode built in since 1989 and up do not have a diode in-line before the IAC plug
What do you all think?
Thank you for your time!!
Just a weird question about the IAC valve, diode and Ohms and not too sure how to explain it.
I have a 87 GT vert. There is a diode in-line going to the IAC.. I've read that all remanufactured IAC valves today now come with a diode built in.
I've read that you are not suppose to have both in-line and IAC valve diodes working at the same time or you will have surging - hunting - hanging idle.
To find out if your IAC has it built in, there should be a "D" on the plastic connector on the IAC or use a DVM on ohms and probe the IAC tabs. One direction should read 7-13ohms and the other way should be infinity.
Everywhere I read, everyone says:
IAC should have 7-13ohms, if not then replace.
IAC should have a "D" on the plastic connector to have a built in diode
86-88's IACs came with non built-in diodes. The diodes are the wiring in front of the plug
89-93 IACs came with built-in diodes.
If your IAC valve has a built in diode, you need to remove the diode that is in-line right before the plug.
sounds straightforward.
What is so confusing me is, I've tested the IAC that was on the car. There was a "3D" on the IAC connector so it should have the diode built in but when I check the ohms, it reads 5.3 ohms both ways!
so I purchased a new one the other day from Rock Auto - brand Standard motor products. After receiving it, I looked for the "D". This one didn't have any markings and also ohm'd out to 5.3 both ways.
so I purchased the best possible part from Rock Auto - brand Motorcraft CX1824 knowing this is original Ford. I received it today and there is a "4D" on it but again when I ohm it, it's 5.3 both ways.
I even contacted Standard motor products customer service to see if they are actually built with the diode even though there isn't a "D" on it and they confirmed yes there is a diode.
I'm completely stumped here why they are not 7-13 ohms and don't want to remove the inline Diode if these now (3) IACs don't have them built in.
Funny thing is all 1986 to 1993 IAC valves, today, all are the same PART#'s
So that tells me an IAC for a 1987 and one for a 1991 must all come with a diode built in since 1989 and up do not have a diode in-line before the IAC plug
What do you all think?
Thank you for your time!!