I just finished a rebuild on a '92 B2200 and have a couple of loose electrical connections that I believe are 'test' connections. If anyone recognizes these and knows what they are OR where they need to be connected it would be greatly appreciated if you would respond to this post. Both wires come from the bundle immediately in front of the carb and under the air cleaner. One of them is a white wire with a green connector and a single contact connection. The other is a red wire with a clear covering tube (hose) and a white connector and single contact connection. Any help would be greatly appreciated. Thanks in advance! I will try and upload a picture with this post.

[IMG]local://upfiles/3875/F05C8E5C61D546E7A00AA52722D18CD0.jpg[/IMG]

 

Not absolute on the red wire but I think that is for the PTC heater. The PTC is basically an electrically heated plate in place of the carb spacer that helps to heat the intake air and carb on cold start. Is that an OE carb? Could not see enough of it but did not look like it. The white wire with green connector is definitely for the Oxygen sensor. Sensor wire snakes around the back of the block at base of the cylinder head and then up under the intake manifold to holding bracket near the intersection of timing belt cover and cylinder head gasket area.

 

OE Stock carb. Thanks for the reply. I think you nailed them.

I got the O2 wire hooked up, don't know how I missed that one. The other wire does run up to the base of the carb, I just cannot seem to find anything to plug it in to! I will keep looking, any advice as to where it should run would be greatly appreciated.

 

One down, one to go eh?
The mating connector should be right there in that harness or group of wires that comes from the right inner fender area. The PTC heater relay is mounted on the right fender just behind the battery. Four wires to it. First of course is the red one that you are looking for. Other three are Red w/ green stripe, Black w/ white stripe and Black w/ red stripe. Once you locate the relay with those four wire colors to it should be a quick find to the wire and connector needed.

 

O.K.

Thank you babyhuey for your advice on this question and all my others. You have been a big help and I'm sure others feel the same. Thanks for the time that you spend in this forum.

I finally got around to removing the air cleaner looking for where to connect this final loose wire. It is a red wire with a clear covering tube (hose) and a white connector and single contact connection. I'm pretty sure that it is for the PTC heater as you stated. It plugs into the base of the carb. I believe that I found the PTC heater relay that you gave directions and wire colors for and traced these wires the best that I could to the front of the carb and still have found nothing to connect the loose wire with. I'm hoping that you or someone else can prove me 'stupid' by tracing the wire and telling me exactly where to plug it in. A picture would be wonderful.

I will try and post some pics and explanations for others to help explain what I'm looking for.

The truck is running like a top. I would really like to get this connected as I'm sure it plays some kind of role, maybe especially when it's cold. I do have some 'rattling lifter' issues (NO SURPRISE) that I will address later, need to drive it more.

PICS: If these come through, they are where the wire plugs into the carb; it's the red wire just right and below of center. This is taken from the passenger side of the vehicle.

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This is the other end, the loose connector.

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I believe that this is the PTC relay, the round one?? or not??

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I had another pic of the wiring harness in front of the carb, but it's not very good, and there are NO VISIBLE loose connections amongst the wires; so I did not post it. HELP!!

 

Hello again mth.

Sorry you are having such a bad time finding that darn wire. Have you tried looking around underneath the intake manifold. The PTC heater wire is in the Engine harness. Other wires for carb are in the Emissions harness. The engine harness basically starts at the positive battery cable clamp, runs down the right fenderwell and crosses over to under the intake manifold. The wires for PTC heater, water thermosensor at front right side of engine area as well as the oil pressure sending unit should separate out of this harness right under the intake manifold. Harness then continues on to the starter and back to all of the switches in the transmission. If you will follow the positive battery cable and harness down to under the intake manifold but before the starter there should be the wire that you are looking for right in that area. I think the wire should run up between the engine and intake manifold between the runners for 1-2 and 3-4 cylinders. Wish I had a pic to send you but no such older trucks in the shop. Hope this helps.

p.s. Good idea there in that I see that you have color coded the vacuum lines for correct reinstallation.

Almost forgot, Yes that round one should be the relay for the PTC heater. It is only energized and PTC heater only operates with coolant temps below 68'F. Just an FYI.

 

Engine harness! Ohhhhhh!! [:-] Super description there Babyhuey, I got it! Thanks a million!!

Exits the engine harness immediately aft of the clamp that holds the harness to the engine block and just above the oil filter. I don't think there was 1/2 inch of wire and then the connector hanging out of the bundle. I could not see it without an inspection mirror.

THANKS AGAIN!! -mth