Anyone know what this goes to? I pulled the dash to fix the heater core and dont know what this goes to.



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in the driver's side kick panel there should be a little black box

which controls your turn signals, and other various car components (eg. factory alarm)

that plugs into the upper portion of the box.

 

Could be the cruise control plug. If your turn signals work , then its not a part of the CPU.

 

here's a pic for you,you can see the upper plug on the cpu,
that's what you have in your hands

 

On second thought, the power steering control unit is located up there in that area. Not all cars have pwr steering but the plug will exist there. Look at the attached jpg and compare your wire colors to the jpg of the pwr steering plug.

 

My guess is cruise control

 

Not long enough to reach the footwell area where the CC computer is located.

 

this car did not have cruise control and signals and all work.

I am having a hard time starting the car. I was wondering if this wire sent signal to the ECU for fuel.

 

What about this one?

 

Look at the jpg of the POWER STEERING control units electrical plug I attached earlier. Compare the colors of the wires in that picture with the plug in your picture.

It's the plug for the power steering control unit. It exists even on cars without power steering. It has no effect on starting the car.

You need to probe 3B with a meter and see if there is batt voltage on it when you hold the key to Start. No batt voltage when you do that means the ECU isn't seeing the Start signal and is not using it's internal Start Map. It would be using the afm for cold starts which means not enough fuel for starting.

 

hailers, i love you to death man and many people here straight up owe you money for the time and help, but I have no clue which one is the 3b on the small plug nor have any idea how to find out or read the wiring diagram. I looked up the FSM pdf and still had no idea what I am looking at.

 

also what is that little plug in the third pic?

 

Little plug looks like a clutch switch plug, but I see one connected in that pic. Anyways, is the engine turning over (starter engaging)?

 

yes, and it will start eventually. just trying to figure out why it isnt getting enough fuel on startup.

 

check out 4B-30 through 4B-33 in the Fuel and emmision control part of the FSM it should explain pin 3B as well as the rest of the pins on the ecu

 

3B is shown in the attached jpg. It's the small plug on the ECU. You are looking at the wire side of the plug in that jpg.

If a car starts fine when hot but very difficult when cold, then you might look at 3B to see if it shows 8-12vdc when the key is put to Start. If it shows that 8-12vdc during Start, then you should look at 2I in the jpg to see if it has somewhere b/t 2-3vdc cold and once the engine is hot shows 0.40 to 0.50vdc (generally a half volt dc). That would show the water thermo sensor is working.

The reason you do the above is: The ECU uses a internal fuel map during START. If the ECU does not see 8-12vdc when you try to start the engine, then the ECU is clueless that your starting the engine so it uses the afm for fuel instead. NOT enough fuel if that happens. Takes a long time to start is the engine is very cold.

Even if the ECU sees the Start signal on 3B, if the water thermo sensor has a open wire b/t it and the ECU, then the ECU will default the water temp to 176*F. That also results in not enough fuel during cold starts. The engine will start fine if the engine temp is hot though because a hot engine is generally around 180*F.

In your last picture, the switch on top of the clutch pedal is the clutch interlock switch. IF the starter turns over when you try to start the car, there is nothing wrong with that switch.

If it turns out you have 8-12vdc at 3B during starts and the water thermo sensor also reads good as described above.............I've no idea why you engine isn't starting good when cold.

 

hailers ur the ******* man. Ill check it tomorrow

 

Ok I started it up with the lead in the harness. I got 4v dc while cranking on 3b. I got .6vdc on the thermosensor plug immediately on startup.

 

is it a vert

 

The little plug in the third pic is for the clutch switch on cars with cruise control.

 

3B would have virtually no voltage at all until you put the key to Start. Then it won't show full battery voltage because the starter is pulling the battery down as it spins, so normally you would see 8-10vdc on 3B. You say you see 4vdc which should be enough for the ECU to trigger the ECU's internal fuel map.

The pin 2I which is a green/white wire, should show 2-3vdc with a cold engine. You say you see .4vdc right upon start up. Something is fishy there if the engine was cold. Was the engine cold? Was the wire color green/white?

I got that last picture wrong. That's not the clutch interlock switch. I had to hold my laptop upside down to finally figure out that I got my answer wrong on that. The clutch interlock switch is shown pretty good on the first picture. None of which has anything to do with cold start problems.

 

Hailers, you seriously are the man.

I went ahead and changed the thermosensor and spliced another good harness to it.

I went ahead and put everything back together and tried to start it and was it was reading over ten volts. The wire in question is green with a red stripe.

The engine was from a vert and has the vert wiring harness in an s5 coupe.
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HAILERS, why when the battery is on its last breath does the car start like it never has a problem. I mean I had cranked it over till you couldnt imagine even lighting a bulb with it being so dead, it starts the car. It has done that a few times.

 

Oh yeah,

forgot one thing. When i first went out there to start the car this afternoon the car cranked right up but ran like ****. It died unless I gave it gas but would rev up a bit, but still rough as hell. I went and checked and I forgot that I had unplugged the AFM the day before doing some trouble shooting.

So with the AFM unplugged it started right up but ran like ****

With the battery on its last electron it starts no problem. WTF?

 

^ with the afm unplugged it will start up and then die. i have similar problems in my vert with really shitty starting and it sounds like it would die if i dont rev it a bit but after a while its ok.

i think mine is started to flood. stupid injectors.

 

I've been talking series four cars and series four wiring. The jpgs I attached are not for series five.