That diode might be in the A/C compressor circuit. I kept all of that stuff because I run A/C and that way the computer can command the compressor to turn on and off (such as at WOT).
Nah, idle air solenoid is connected to a separate harness that is on the engine itself. And I have verified it works. The video I posted last summer of it running shows what I mean by high idle: You can hear that it does slow down after a minute or so of running. It just seems like it's running way too fast on initial start up. I'll see about hooking a tach up to it this weekend and see exactly what RPM it is running at. I'll bet you're right. It's in the right general area that it could have went to the A/C compressor. I'll see about getting some pics up tomorrow evening.
my ranger idles up for awhile untill it's warm. starts up at 2500 or so, then slows to about 2k, then slowly gets around 800-1k
Oh, its for a 2.3... I was looking at 5.0 schematics trying to figure out why I could not find the colors you were specifying.
Double check for vaccume leaks,The IAC may also need to be cleaned out the bad about gumming up on the 2.3's.
You can try unplugging the IAB as well to see if the idle changes. The idle should drop as soon as you unplug it.
I went back to Pull-A-Part today and found a 4 cyl. '91 Mustang Convertible with an absolutely perfect harness in it. The car itself was totally ate up with rust, it must have been from up north somewhere. Anyway, I now know what all but 1 connector is for on the harness. Turns out I was missing several sensors, which leads me to believe may be causing my high idle issue? We'll see tomorrow when I get back up to NC to test this all out. I went ahead and spent a couple of hours pulling the harness since it was in such nice shape, got it for $14.06 with the sensors I was missing attached. My old harness was pulled out of the car my engine came from by the guy I bought the stuff off of, and he wasn't very careful about it. There were skinned up wires in several places, cut wires, and now I see that he left several sensors that I need in the car instead of pulling them with the harness. So I'm going to work with this new harness instead. Here's some pics: Still have one unkown plug here. In all three of the Mustangs I looked at in the junkyard, this wire was just dangling loose. So I don't know. Now that I have my old harness to tare apart and mess with, I'm going to trace it up through the harness and see where it goes. The electric fan power will hopefully work out awesome. Just plug it into my Taurus fan and the computer should handle turning it off and on as needed. If that does work out, I'll probably put a small light next to my temperature gauge just to be sure that the fan is turning on and off when needed. The above pic shows 4 of the plugs that I was unsure about before, along with the sensors I was missing connected to them. From right to left: the BAP sensor (barometric absolute pressure), what I assume is some sort of temperature sensor that is located in the hose going to the heater core, a plug that went to some part of the A/C system up near the firewall, and the EGR control solenoid which lets the computer control the EGR valve depending on driving conditions. The red tube goes to manifold vacuum, green goes to the EGR valve, easy enough.. More plugs. From right to left, the HEGO (Heated Exhaust Gas Oxygen) sensor plug, unneeded air bag sensor plugs and wiring that I will remove, MAF (Mass Air Flow) sensor plug, ACT (Air Charge Temperature) sensor plug, charcoal canister purge solenoid plug (I still need to find the right charcoal canister), and the wire that supplies power the the A/C compressor clutch, which is the wire with the diode on it I was talking about earlier in the thread. The green plug in this pic is still causing me problems. I need to find a correct pin out for this plug.
Jaime, Just a tip... make sure you mount that BAP sensor right side up. It doesn't work right mounted side ways or pointed down. Looks like you've got yourself a nice project there an I'm sure you'll have learned a lot when you're done.
Tomorrow I'll check my car and see if I can tell you what that unknown plug is for... I've been sitting here looking at it and I just can't remember, it's been too long since I did mine.
the elec fan will the the relay module to work correctly. you can use the the mavs charcoal canister and just need the purge solonid in the vac line from the canister to the intake manifold. the green plug as you probly already know has the wires that go into the dash to controle the check engine light, the ignition switch, the fuel pump and a few more things i cant rember right now.
Not unless there is two compressors, or it plugs into something else that controls the A/C compressor. I already have the plug that goes to the compressor clutch itself identified. Thanks for the info. I'll probably spend most of the day tomorrow figuring out locations for stuff like that, as well as getting the harness rearranged how I want it. I need to get my radiator hoses and serpentine belt figured out as well, so that I can run the engine for more then a minute and a half...
