CEL light. What is this plug?
 

FC S5 non turbo

My check engine light has come on after changing the diff, clutch, oil pan, and omp gasket. Tried resetting the ecu by disconnecting the battery but the cel light comes up immediately.

First thing is to check if I plugged all the oil pan sensors back together. As I looked under I saw a sensor I didn't see before. Pictures below

https://cimg9.ibsrv.net/gimg/www.rx7...9c12a38130.jpg


The white plug is the OIL level sensor from the oil pan. This other one I have no idea where it goes.

Also I tried pulling the code out using a jumper but the cel light won't blink? :(

What color is the wire/wires going to it. I can't tell from the picture.

I believe it's black with a red stripe. It seems to come from the same wire where the oil level wire is

Could be the sub zero sensor which is found at the oil pan (not sure this was on the S5 though).

Sub zero was not on the S5.

OP, let me dive into the FSM and I'll get back with you shortly. :)

sure looks like it is for the AWS system on the S4 since it joins the oil level sensor wire in the loom.

if so it is not important.

Thanks guys! Still can't figure out my cel light.

What's even more strange is that I'm trying to pull the code out myself using banzai racing tech document.

Have the wire jumped but the cel light doesn't blink :/

which wire jumped? on the S5 there is a green 1 pin wire that just goes to ground

Yeah its the single wire right above the air box, right next to the 3 prong green one. I have that jumped and I turn the key forward 1 click but nothing happens :/.

key on engine off, so 2 clicks

Wait what?

The CEL check connector is near the battery on an S5, not the air box!

To clear things up, what year model car do you have and if it's an 88, specify the manufacture date.

And the wire color is Orange.

Model is at the top of post. 89 rx7 non turbo.

I'll double check the wire I'm supposed to jump. I may have read the wrong manual or misinterpreted it

Jumped the wire correctly this time.

Codes are.

11 air temp
17 o2 sensor feedback?
51 fuel pump relay?

The o2 sensor is an easy fix but how do I go about the rest?

fuel pump relay is a limp home. off the top its the fuel pump SPEED relay which is under the airbox, sort of behind the headlight. you should look at the air temp sensor too.

codes 11 and 51 might cause a code 17, so i would fix the other two first

Well I know that when I put my racing beat exhaust headers in, the dude whacked at my o2 sensor so that's probably not working.

Though the car doesn't seem like it's in limp mode and it doesn't bog down on WOT even up to redline. Perhaps it is only the o2 sensor causing the other 2?

well if the o2 is broken, then yeah maybe you should fix that.... the o2 sensor can't cause a relay to be bad though