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O2 sensor issues?

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Old 06-06-2019 | 04:50 AM
  #166  
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Originally Posted by randy61
This diagram is incorrect.
Yes I know. This would be the workaround you were looking for. Heater power would be provided by Yellow, which should be hot only when Key On, and the Oxygen Heater Relay itself would be powered by Orange. Although your issue is Orange is hot all the time (as opposed to hot only when Key On), since ECU decides when to provide power this should work.

However, the best plan is to figure out how the fuel pump gets power without a relay. Sooner or later, one of these repairs or workarounds might end up smoking the whole harness.

BTW, what are the Part#s of the relays for the Oxygen Heater and the Fuel Pump?

Also, I believe you have 4 fusible links in and around the starter relay. Are they all good?
Old 06-06-2019 | 05:04 AM
  #167  
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Originally Posted by randy61
According to the fuel injection manual, when the ECU determines high exhaust gas o2 heater is no longer needed and ECU completes the relay coil ground circuit.
Right:

High exhaust gas rates = heater off
WOT = sensor off
Old 06-06-2019 | 06:27 AM
  #168  
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Originally Posted by cruiser54
do you guys have the Renix Fuel Injection Manual in PDF form?
Oddly, no.
Old 06-06-2019 | 06:54 AM
  #169  
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Originally Posted by randy61
The issue is pin 87 on the FP relay is hot with key off.
Time to start ripping the harness apart.

That wire (F22 14OR) goes to a ton of stuff. With relay out and key off, check it at the EGR solenoid, the fuel injectors, power steering pump, and the fuel pump. We already know it's hot at the Oxygen Sensor Heater. You checked it at the AC and noted that it's not, so something is askew.
Old 06-06-2019 | 09:14 AM
  #170  
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Originally Posted by Dave51
Oddly, no.
Renix Fuel Injection Manual PDF.
https://drive.google.com/file/d/0B7L...lQYl9vR2c/view
Old 06-06-2019 | 09:30 AM
  #171  
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Originally Posted by randy61
Still the one with 2 page 58s and no page 59.

Page 59.

The one with all the secrets.
Old 06-06-2019 | 09:45 AM
  #172  
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Originally Posted by Dave51

BTW, what are the Part#s of the relays for the Oxygen Heater and the Fuel Pump?

Also, I believe you have 4 fusible links in and around the starter relay. Are they all good?
The junkyard jeep all the relays were the same numbers as were mine, and they matched the junkyard jeep 56002959. Not sure if that is a part number.

All the fuse links going to starter relay were are good.

Going to try and check ohms between pin 85 on FP and pin A5 on the ECU plug and pin 85 on O2 and pin A7 on ECU today. Those are the relay pins the jumper wire has been squatting in.

Forgot to mention. The large orange wire that had the coating missing up close to the O2 relay holder (post #67), the junkyard relay holder had the exact same missing orange wire coating.

Also was lucky enough to nab the junkyard ECU. Strange it was still on it being that someone took half the dash harness and the steering column.
Old 06-06-2019 | 09:59 AM
  #173  
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Originally Posted by Dave51
Still the one with 2 page 58s and no page 59. Page 59. The one with all the secrets.
Maybe the pages were just incorrectly numbered and the last of the two pages 58 is actually supposed to be page 59.
And maybe the missing secret page is a rumor..
Old 06-06-2019 | 11:48 AM
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Originally Posted by randy61
And maybe the missing secret page is a rumor..
Oh yeah?

And maybe it could have Gal Gadot's cell phone number there too!
Old 06-06-2019 | 01:22 PM
  #175  
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Originally Posted by randy61
Going to try and check ohms between pin 85 on FP and pin A5 on the ECU plug and pin 85 on O2 and pin A7 on ECU today. Those are the relay pins the jumper wire has been squatting in.
.
Got continuity on both pins. Maybe ECU is bad.
Old 06-07-2019 | 03:39 AM
  #176  
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Originally Posted by Dave51
Oh yeah?

And maybe it could have Gal Gadot's cell phone number there too!
If it has Sofia Vergara's address then I got to find that missing page.
Old 06-07-2019 | 04:19 AM
  #177  
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Originally Posted by randy61
Going to try and check ohms between pin 85 on FP and pin A5 on the ECU plug and pin 85 on O2 and pin A7 on ECU today. Those are the relay pins the jumper wire has been squatting in.
Originally Posted by randy61
Got continuity on both pins. Maybe ECU is bad.
Can you explain that?
Old 06-07-2019 | 11:36 AM
  #178  
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Originally Posted by Dave51
Can you explain that?
The jumper wire needed between the FP and o2 to get power to FP. Pins 85.
Ohms test was to determine if they were getting grounded to the computer because those pins are grounds.
Old 06-07-2019 | 12:31 PM
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Originally Posted by randy61
Got continuity on both pins. Maybe ECU is bad.

Please describe how you tested continuity. Details matter.
Old 06-07-2019 | 01:52 PM
  #180  
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Originally Posted by BlueRidgeMark
Please describe how you tested continuity. Details matter.
Google 'How to do a continuity test"


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