EGR Temperature Sensor trouble code

[Woot!]

What color wires are coming out of the connector that you circled in yellow in the first pic?

The sensor under the plenum that is cooling related is the ECU temp. sensor, and I thikn the others are your knock sensors.

Heath

One wire is GREEN with a YELLOW stripe and the other is BLACK with a YELLOW stripe.

So is it possible that the yellow trail is the knock sensors? What will it do if they are not plugged in?

I have had the car started and idling for the last 20 min and it hasn't thrown any codes yet.

[Q451990]

Alright... I just made my last trip to the garage for the night. I don't think that connector you circled in yellow should be there. If it has two black wires hanging out of it - maybe it's an extra sensor dangling down there? I'm getting pretty tired, so I'll look at this tomorrow at some point. If you start the car and it runs like crap, swap those connectors back for now...

Heath

[Woot!]

Hey, thanks for the help. The car runs fine how it is now. I will talk to you about it some more tomorow

[Q451990]

Well, after some more looking and some thought with a little sleep, I have no idea what that connector does. I have to wonder if your car's donor engine, which could have come from anything from a 90-93, had some accessories that we don't have. Maybe that connector had something to do with traction control, HICAS, active suspension, etc. In any case I think we have the EGR temp. sensor hooked up correctly now.

To answer your question, that connector does not feed the ECU Temp sensor or knock sensors. Those are all part of one subharness, and I see that in the picture connected correctly.

I think the next step is to pull codes on your ECU again and see what you come up with. Remember that the OBD1 (pre 1996) ECU only sets of the "check engine" light for very major things - so you can't rely on not having codes just because the light isn't on.

Heath

[Woot!]

The light hasn't come back on this morning yet.

So you are saying that the ECU will still throw codes without the engine light coming on

I just pulled the ECU codes again and it gives me the code 55, and if I remember right that just means that all is well?

[Q451990]

55 =

That just means that all of the sensors are either not shorted or open (depending on what the ECU is looking for) - not a guarantee that everything is performing properly, hooked up correctly, or that everything is ideal. OBD1 ECUs are relatively dumb compared to the later OBDII ECUs that are able to actually look at the data and see if it makes sense....

In any case you're moving in the right direction! Next is figuring out what those mystery tubes and hoses should be doing.

Heath

[Woot!]

Alright Heath, I just found some more confusion...or maybe a solution?

Ok, I was just looking at the 2 original mystery tubes and while I was looking I found 2 more . Here are some more pics:

The original ones are circled in yellow (where the small orange x is is just a bolt sticking out) and the new ones are circled in red (they change to the metal tubing about 2" down the line).

Following the second 2 mystery lines under the plenum.

Shows where the camera was when I took the next picture:

Zoomed up under the plenum. The red is the second pair of mystery lines. Circled in yellow is a injector also circle in the next picture.

Red still following the 2 lines. Yellow circling the injector as circled above.

What on earth could they be? I unplugged all of them and started it and nothing came out of them so I don't think they have anything to do with the cooling system.

[Q451990]

I agree that they aren't cooling lines. I'll have to find some time to look this weekend. My car still has all of the front covers on the engine, so it takes a little more effort to see in some of those areas.

Heath

[qship96]

Wow Heath,you really are an example of all the good here at Nico! Keep up the good work!

[Woot!]

So does anyone else know what these 4 hoses could go to??

[goody90q45]

Read the FSM. The first few pages of the EF&EC section have some easy to understand drawings and schematics that will help you decide where the mystery hoses go. They should be pretty easy to trace once you understand the emissions system.