Sooo I have a 1990 iroc z with a crate motor in it. It is tpi and 5.7l. The bottom picture is of my cold start valve in my car. I read that in 1990 they didn’t have a cold start valve because they changed to something else. I need help finding the part and connector to it. I called the part stores and there’s no part number for a 1990 camaro and some of the 80s camaro it looks like it’s in a different spot. On mine it’s to the left of the coolant temp sensor. Any information would be greatly appreciated.

This is a picture I found on the internet just so you can see the cold start valve better.

This is a pic of the cold start valve from my car. It has gotten melted or corroded so there is nothing attached to it.

 

Your picture isn't showing the cold start valve , it's showing the switch that controls the cold start valve (injector) . Since your car is a 1990 , your correct that it's not supposed to have a cold start injector , the ECM is supposed to richen the mixture for a cold start . Were I forced to guess , I'd guess you have an older intake manifold that still has the cold start components but that it isn't hooked up because your (hopefully) 1990 ECM is handling that function itself .

Does the car start badly when the engine is cold ?

 

If you do not have the cold start injector (circled in the photo below) you can leave the sensor disconnected. They probably just have it there rather than a pipe plug to fill the water passage hole.

 

The car fires right up whenever. I read about people bypassing the switch as well. It’s crazy cause it didn’t have any wires or anything connected to. It just looks like the connection like melted off. I wonder if someone just put that there as a plug. Also how do I check if it is sending the right fuel mixture in the computer. I tried to read the codes From the ALDL but I recent unhooked the battery to replace a leaking heater bypass valve. So I have to wait for the codes to pop up again. The engine is slow in changing gears and I read that could be because of the colant temp valve. So I bought that and I’m going to install it soon. I just saw nothing plugged in to what looked like a sensor and it freaked me out lol

 

The cold start injectors can be found out there in the used market, but the switch itself is pretty much unobtainable. Ran into thicknesses rebuilding an 88 Vette. As OrangeBird said above, your ECM should not be using the cold start. I solved the problem on my 88 by burning a chip with an 89 program.

Maybe your TPI system was added later?

 

The "engine" doesn't change gears. That's the transmission. Which is entirely mechanical in it's gear changing - so not related to any of the sensors on the engine. Change your transmission fluid and if that doesn't help you may need to have the transmission overhauled.

The "9th injector" cold start assist is not used on a 1990. You obviously have an older intake on a newer car and this is not connected because the car has no provision for powering it and the car's computer doesn't require it. So ignore it.

GD