Wiring Harness Solutions?
Thread Starter
On The Tree
Joined: Mar 2011
Posts: 184
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Wiring Harness Solutions? Today, I received my "adapted" wiring harness from Hawks. Had a few questions and Bruce answered a couple, but then it was the end of the day for him. He told me that I needed a 3-wire coolant temp sensor (from a 98 Z28). I have a two-pin coolant temp sensor - so I guess that I have to adapt to the harness! I went to the parts store, and they could not find any 3-pin and only pulled up the same exact that I have 
The connector looks like a direct fit for the oil pressure sending unit located on the back of the block. But the wire is in the loom that has the driver's injectors. Also, the four wires that drop down from that loom: alternator, knock, and the two I am trying to track down. The second I am trying to track down is a 3-pin and I think should be the cam sensor - as it has 3 pins. However the connector does not fit. The cam sensor unit has a little protrusion inside it - the connector in question is smooth all round.
I hope you guys can help shed some light on the weekend. Here are some pics
The connector looks like a direct fit for the oil pressure sending unit located on the back of the block. But the wire is in the loom that has the driver's injectors. Also, the four wires that drop down from that loom: alternator, knock, and the two I am trying to track down. The second I am trying to track down is a 3-pin and I think should be the cam sensor - as it has 3 pins. However the connector does not fit. The cam sensor unit has a little protrusion inside it - the connector in question is smooth all round.
I hope you guys can help shed some light on the weekend. Here are some pics
Thread Starter
On The Tree
Joined: Mar 2011
Posts: 184
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The first two pics are the "coolant sensor connector" as told by Hawks, but it looks like a fit for the second pic - the oil pressure sending unit. The third pic should how tight the loom is from injector--alternator---knock sensor. That connector will not even reach the coolant sensor fitting.
These pics show the 3-pin connector on the harness and a bad angle photo of the cam sensor. You can barely see the protrusion inside the sensor that will not allow a "smooth" connector to seat.
The third pic is a sensor I can't figure out. One tan wire in that connector near the firewall.
Hope you guys can help on the weekend.
Brian
These pics show the 3-pin connector on the harness and a bad angle photo of the cam sensor. You can barely see the protrusion inside the sensor that will not allow a "smooth" connector to seat.
The third pic is a sensor I can't figure out. One tan wire in that connector near the firewall.
Hope you guys can help on the weekend.
Brian
go to the gm dealer to get the 98 coolant sensor... it allows for a gauge hookup....
first pic looks like a maf sensor connector ? not a coolant temp
single tan should be your oil pressure i think....
what motor is it? VVT?
first pic looks like a maf sensor connector ? not a coolant temp
single tan should be your oil pressure i think....
what motor is it? VVT?
Thread Starter
On The Tree
Joined: Mar 2011
Posts: 184
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LS2 going into an '89 Formula.
That single tan wire has an oblong connector - will not fit into the oil press sending unit.
I had all the correct connector on the original harness. Why would they come back different? I trust Hawks - but it's the weekend and I want to get going.
Even if I go to a dealer and get a 3-pin coolant unit, that connector will not reach. The injector connection above, the alternator, and the knock sensor attachments have the loom stretched tight and the small amount of wire will not reach the fitting.
That single tan wire has an oblong connector - will not fit into the oil press sending unit.
I had all the correct connector on the original harness. Why would they come back different? I trust Hawks - but it's the weekend and I want to get going.
Even if I go to a dealer and get a 3-pin coolant unit, that connector will not reach. The injector connection above, the alternator, and the knock sensor attachments have the loom stretched tight and the small amount of wire will not reach the fitting.
The LS2 used an oil pressure sensor, you need to get an LS1 sensor for the tan wire with the single white connector so the gauge works. Should thread right in. I've used one of his harnesses before and everything hooked right up.
Thread Starter
On The Tree
Joined: Mar 2011
Posts: 184
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Frustrated So, I've driven all over town. No one has them in stock (dealers,Napa,autozone,o'reilly's). The three wire coolant temp sending unit is GM # 12551708 - I have not verified the pin configuration, but it is a 3-pin=$30. The Oil Press Sending unit is GM #12559781 - I have not verified the connector configuration (oblong), but is 1 pin=$50.
$80.00 added to the cost of the "conversion" harness makes me feel like I am converting to the harness, rather than what I paid for; a conversion harness to what I have. It seems a standard LS1 configuration was used for the conversion harness, and I have an LS2. I'm concerned that if I switch to LS1 sensors, the correct signal outputs to the E40 will be different (2 pin coolant sender for LS2 compare to 3 pin coolant sender for LS1).
The O2 sensors connectors are square; the O2 sensors from a GTO LS2 are flat (both 4 pin) and have different part #'s. Not sure if the difference is only in the connector type, or in output signal to the ECM as well. Anyone have knowledge. I would think an O2 is an O2.
I guess I'm stopped til I can speak with Bruce on Monday
$80.00 added to the cost of the "conversion" harness makes me feel like I am converting to the harness, rather than what I paid for; a conversion harness to what I have. It seems a standard LS1 configuration was used for the conversion harness, and I have an LS2. I'm concerned that if I switch to LS1 sensors, the correct signal outputs to the E40 will be different (2 pin coolant sender for LS2 compare to 3 pin coolant sender for LS1).
The O2 sensors connectors are square; the O2 sensors from a GTO LS2 are flat (both 4 pin) and have different part #'s. Not sure if the difference is only in the connector type, or in output signal to the ECM as well. Anyone have knowledge. I would think an O2 is an O2.
I guess I'm stopped til I can speak with Bruce on Monday
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Thread Starter
On The Tree
Joined: Mar 2011
Posts: 184
Likes: 1
This page from Potak's swap manual says it all. I read this, but never sank in and the different connectors on the harness threw me into frustration like Christmas morn with no batteries.
Bruce is sending the new sending units, harness extension for the knock, and the O2 sensors should not be a prob.
Bruce is sending the new sending units, harness extension for the knock, and the O2 sensors should not be a prob.
As long as the O2 sensors are 4 wire , then usually they use the same color wires , 2 purple a pink and I think a gray , make sure they go to the same wires after the connector .
Staging Lane
Joined: Sep 2009
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O2 sensors are an item that has a service interval. They can become slow to respond for a variety of reasons. Unlike a crank or cam they can we operating but not most efficiently, and unlike an ect for instance, where a few degree temp difference isnt a big deal, the mV reading difference can affect your fuel trims if you are scanning and tuning, or they could be dead altogether and you would never know it if you aren't scanning/tuning.
