Hello,

Anybody know where COR is on a 1990 Toyota pickup? It's supposed to be under the kick plate on the passenger side but I can't seem to find it.
Is it further up and should I take the dash off or is it somewhere else?

Thanks!

 

You may have to remove the glove box; I think it's more or less even with the bottom of the glove box.
There are better photos than this one; this is what I have.

 

Found that I was missing the COR and the wiring that goes to it.
How can my truck run with out it and what damage may have been caused by not having it?

 

Truck is also missing a EFI fuse.

 

The principal purpose of the COR is to save your life. Might help explain why the prior owner sold it to you.

The COR connects the fuel pump to (switched with key-on) 12v. The relay has two coils. The first is activated (closing the relay) with the key to STArt, and the second is activated by a switch in the VAF when the engine starts sucking air. When you release the key, the second coil in the relay keeps the relay closed and the fuel pump running. Why go to all this trouble, instead of just hooking the fuel pump to the ACC line? When you get in an accident that breaks a fuel line (so the engine stops running), you want your fuel pump to immediately shut off.

So I'm going to guess the genius you got the truck from just re-wired the fuel pump wire to some line that is hot with key-on. Home-made wiring should be easy to find (hardware store crimps, if you're lucky). The wire to the Fuel pump should be solid blue, if that helps. It also connects to the FP pin of the diagnostic connector; that would be an easy place to jumper the fuel pump so it runs all the time with key-on (though jumping it that way wouldn't explain why they went to all the trouble of removing the COR.) The white-red wire TO the COR comes from the EFI relay, which gets it's 12v from the EFI fuse (Black-White) If the EFI fuse is also missing, you may have a lot of work ahead of you.

Keep us posted; I'm really curious about what you are up against.

Which leads to the next question: why were you looking for the COR?

Last, good job on the photo. As you could guess, I'm a big fan of clear photos with labeling.

 

That's some interesting info, I'm surprised my truck has ran all these years with minimal problems. I bought it in 2013 and I'm the third owner.

I tore everything up looking for the wiring bundle but couldn't find a trace of one, I was beginning to wonder if my truck even ever had an COR.

The reason I'm trying to find it is my truck won't stay running, it turns over fine but won't idle. It will run jumpy if I keep my foot on the gas but if I let off it dies instantly. The exhaust smells like unburnt gas too, like it's just dumping in there.

I've checked my vacuum lines and distributor but didn't really find anything. One vacuum line was broken but I already replaced it. I'm just trouble shooting away!

Would it help to buy a new EFI fuse?
That probably won't fix my lack of having a COR.

 

If the EFI fuse HOLDER is correctly wired, then nothing will run with the fuse out. So replacing the fuse now should make no difference.

Fuel pressure drop-out probably wouldn't lead to gas smell, but testing the COR is dead-simple (and you don't even need to locate the relay). I can hear my fuel pump while standing at the diagnostic connector, when I jumper FP to B+ with key-on. In your case, you may be able to hear it with just key-on, but use the jumper anyway just in case you have a "hidden" COR somewhere. If the truck runs well with the jumper, suspect the COR-VAF circuit.

One cause of no idle (and gas smell) is misfire. Use the inductive lead of your timing light on each spark plug lead, so see if you can find one (or more) that isn't firing. (And while you've got the gun out, check the ignition timing. That can cause your symptoms.)

 

Thank you!
Ill give those tips a shot and report back later.
I need to pick up a timing light and some beer 👍.

Thanks again!

 

https://www.harborfreight.com/timing...nce-40963.html

HF used to have a $20 timing light, but if you pick this one up tomorrow there's a 25% coupon!!

 

My truck doesn't appear to have diagnostic connector next to the passenger side fuse box. It isn't under the driver side kick plate either.
​​​​​​Is it somewhere else ?

 

Haha I was going to get that one from HF with a 20% off coupon from the paper.

 

Wait, hold up just a minute....

What engine do you have? 22R carbureted, 22R-E fuel injected, or 3.0L 3VZ-E??

If you happen to have the last of the 22R carbureted trucks, what you have makes sense. The 22R engines did not have a COR as the fuel pump is mechanical (not electrical) and driven off of the engine. The 22Rs also did not have an EFI fuse or a diagnostic box because there is no Engine Computer.