timing jumped...?

[BISHILVR]

Yes thats right. The only ones that should read zero ohms are grounds to the ecu. If you encounter any that read zero, post the pin numbers on here. How do you have the fuel pump wired? same as stock? If not then it could be a problem if you are pulling amperage through the ecu to feed the fuel pump in some way. Maybe try running a positive from the battery right to the fuel pump temporarily and disconnect your other fuel pump wiring and see if you can go a few trips without wiping the ecu.

 

[95-talontsi]

I have the fuel pump rewired how it says to on here.

Ill get it all checked out on thursday.

thanks for the help

 

[95-talontsi]

I tested the wires with the ohm meter these are the ones i couldnt get a reading from.
I didnt test the wires i cut though.. I will connect them and test them if you think its necessary.

37 Power steering pressure switch
45 AC switch
41 Generator FR terminal
60 O2 sensor heater (front)
58 Engine ignition signal
88 Camshaft position sensor
87 Closed throttle position switch (Idle switch)
85 Barometric pressure sensor
72 Intake air temp sensor

 

[BISHILVR]

I tested the wires with the ohm meter these are the ones i couldnt get a reading from.
I didnt test the wires i cut though.. I will connect them and test them if you think its necessary.

37 Power steering pressure switch
45 AC switch
41 Generator FR terminal
60 O2 sensor heater (front)
58 Engine ignition signal
88 Camshaft position sensor
87 Closed throttle position switch (Idle switch)
85 Barometric pressure sensor
72 Intake air temp sensor

So your saying that these were the ones that read more than 0 ohms right? Zero ohms is a short btw.

 

[95-talontsi]

So your saying that these were the ones that read more than 0 ohms right? Zero ohms is a short btw.

No those are the ones that read zero ohms.

 

[95-talontsi]

37 Power steering pressure switch
45 AC switch
41 Generator FR terminal
60 O2 sensor heater (front)
58 Engine ignition signal
88 Camshaft position sensor
87 Closed throttle position switch (Idle switch)
85 Barometric pressure sensor
72 Intake air temp sensor

So could one of these being shorted cause the others to be read as shorted? I just dont see all these could be shorted out.

 

[BISHILVR]

No, I would say that you are'nt real experienced with an ohm meter. First a short will read the same as when you touch the probes together, whatever the meter reads when the probes are touched together (exactly that number) is what a true short will read when you find them. I would'nt believe that all of those would be shorted. You DID unplug the ecu when you tested those wires right? If not, then unplug the ecu and retest, also disconnect the battery terminals (always) when doing any ohm test.

 

[95-talontsi]

Oh ok, I figured when the meter didnt move that it was reading zero ohms. Yes I had a couple that pegged the meter instantly when I touched them. I also had the battery hooked up. I will retest tommorrow then, Since I dont work.

 

[95-talontsi]

ok I think I got it right now. here are the ones that read the same as when the probes were touched together.

81 Sensor impressed voltage
91 Park/Neutral position switch (used on ATs only)
82
36 Check Engine light
13 Power supply
8 Fuel pump relay
26
16 Boost meter


91,82, and 26 i am guessing are grounds? since I have a 5 speed.

Im pretty sure I did it correctly that time.

Is boost meter for the gauge in the dash?

What should I check now? Should I connect those wires I cut? and test them?

 

[BISHILVR]

Those seem normal except for the sensor impressed voltage, that pin I'm not sure should be zero ohms. Yes reconnect the wires you cut and check them.

 

[steve]

Here's what those really are.

8 Fuel pump relay control
13 Ground
16 Boost meter
26 Ground
36 Check Engine Light
81 +5v Sensor Power
82 Ignition IG1
91 Park/Neutral position switch (used on ATs only, grounded on MT's)

Depending on how the ignition switch works you may see continuity to ground on the lines that get power from the ignition but 13, 26, and 91 are grounds. 81 shouldn't be a short to ground.

Steve

 

[95-talontsi]

does 81 go to something in the engine bay? Or am I going to have to attempt to trace this wire?

 

[steve]

does 81 go to something in the engine bay? Or am I going to have to attempt to trace this wire?

Sure it goes to every sensor that uses +5v. I don't have my 2G wiring diagram handy to list all of them for you.

Steve

 

[95-talontsi]

I have a chilton but I dont understand the wiring diagrams.

 

[steve]

I have a chilton but I dont understand the wiring diagrams.

That seems to be a common problem. Grap the turbo MFI diagram and try and trace the signal.

The 5v sensor power comes from ECU pin 81 on a green/yellow wire and runs to the MAF (for both the IAT and barometric pressure sensors), TPS, and MDP sensors.

From your diagram, tell me which pin on each sensor connects to ECU pin 81.

Steve

 

[95-talontsi]

I still dont understand. 81 connects to all sensors in a way. Ill scan the picture at work and post it up for you.

 

[steve]

I'd love to see that picture. I'm reading the 2.0 turbo MFI circuit diagram out of the factory manual.

What do you mean "in a way", perhaps that's where the confusion is.

Steve

 

[BISHILVR]

I still dont understand. 81 connects to all sensors in a way. Ill scan the picture at work and post it up for you.

81 Is the five volt reference signal from the ecu to the sensors, so it is going to connect to alot of the sensors.

 

[95-talontsi]

here you go...
you will have to save it to zoom in. it should stay clear.

You must be logged in to view this image or video.

 

[steve]

That's a cleaner schematic but it shows almost the same information. You's doesn't let you know that there are sveral sensors inside the MAF.

Since I can read these, you need to try. Post up what you think are all the sensors connected to +5v using that and which pin is it on for each. Without seeing what you think is going on I can't figure out where your going wrong.

If your not interested in doing the homework just let me know and I can unsubscribe the thread.

Steve

 

[95-talontsi]

Im willing to do my homework, I want any help I can get cause I cant figure this out on my own. The thing is I dont know what I need to do. Do I need to use the ohm meter and test the solenoids in the engine bay?

 

[steve]

The first thing I want you to do is forget about everything else and look at your schematic and tell me what you think are all the sensors connected to +5v using that and which pin is it on for each.

If you can't read a schematic the rest is pretty pointlless.

Steve

 

[95-talontsi]

well to me it looks like it goes to the fuel tank diff pressure sensor and that goes to pin c61 which also runs to volume are flow sensor which is connected to d90,d85,d72, and a19 then it runs to the tps which goes to d87 and d84 then it connects to the manifold diff pressure sensor which is connected to d73 then that runs down to the front heated oxygen sensor which connects to c60 and d76 then it runs to the rear heated oxygen sensor which goes to c54 and d75 then it goes to the idle air control motor which connects to a4, a17, a5, and a18. then it connects to the crank shaft position sensor that goes to d89 and a13 then that goes to a26 and d91 then it goes to the camshaft position sensor which goes to d88. also from the air flow sensor it connects to the turbo wastegate solenoid that goes to a11 which goes to the ful pressure solenoid that goes to a3.

Thats how I see it.

 

[steve]

well to me it looks like it goes to the fuel tank diff pressure sensor and that goes to pin c61 which also runs to volume are flow sensor which is connected to d90,d85,d72, and a19 then it runs to the tps which goes to d87 and d84 then it connects to the manifold diff pressure sensor which is connected to d73 then that runs down to the front heated oxygen sensor which connects to c60 and d76 then it runs to the rear heated oxygen sensor which goes to c54 and d75 then it goes to the idle air control motor which connects to a4, a17, a5, and a18. then it connects to the crank shaft position sensor that goes to d89 and a13 then that goes to a26 and d91 then it goes to the camshaft position sensor which goes to d88. also from the air flow sensor it connects to the turbo wastegate solenoid that goes to a11 which goes to the ful pressure solenoid that goes to a3.

Thats how I see it.

Each line going into a box doesn't connect to the other lines going into the box.
It's better to think of each box as an end point until you know what the boxes do and how they work.

Lines that cross aren't connected unless there is a dot at the intersection.

So the +5v sensor power (ECU pin 81, D81 in the picture? Green/Yellow) goes to:

Fuel Tank Diff Pressure Sensor (2.4L only) (3)
Volume Air Flow Sensor (the MAF Sensor) (1)
Throttle Position Sensor (1)
Manifold Diff Pressure Sensor (3)

That's it.

Since your schematic doesn't give you pin # your at a disavantage when it comes to trouble shooting. I've added the pin numbers on the sensor.

So with those sensors unplugged, when you measure on the ohms scale pin 81 at the ECU harness (one probe to the harness pin and the other to ground) you should see infinite resistance (open) the same reading as when your probes aren't touching. If you read 0 ohms then that wire is shorted some where.

With the sensors still disconnected but the ECU plugged in and ignition on you should measure 5v on the volts scale at each of the sensor harness connectors. If you don't read any voltage then the wire is open somewhere.

Does this help make any sense of the diagrams?

Steve

 

[95-talontsi]

That does make alot more sense. Will it be safe to plug my ecu and turn the key to on to test the sensors? Seems like I would fry my computer again doing this.

Also you will have to tell me how to use the volt scale if you would please.

I havent gotten my next ecu yet so I cant test until I get it.