Author Topic: Any TBI experts out there? (New Body Style)  (Read 14255 times)

Offline Dr_Snooz

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Re: Any TBI experts out there? (New Body Style)
« Reply #15 on: January 17, 2015, 09:11:33 pm »
I don't know. I was neurotic about labeling everything because this was my first domestic rebuild, first big block, first truck, etc. Then when I put it all back together, I found that stupid connector sitting there giving me the stink eye. No label, very short, nothing anywhere close to it. I can only assume that it was some kind of option that my truck doesn't have. Sorta like back in the day, you'd buy a car without a clock but behind the blank-out plate was a wire for the clock. I'm sure I'll figure it out someday when I go to turn something on and it doesn't turn on. I'll spend a week and a half troubleshooting before finding that stupid connector and remembering.
1989 Chevy Suburban V-2500, 5.7L, TH400

1990 Chevy C-3500 Ext. Cab, 7.4L, 3L80

2009 Chevy Silverado 1500 WT 4WD, 4.8L, 4L60

Offline pholliday1

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Re: Any TBI experts out there? (New Body Style)
« Reply #16 on: January 18, 2015, 06:16:36 pm »
Shooting from the hip here but might be some sort of O2 sensor plug
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Offline 78BIG-TEN

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Re: Any TBI experts out there? (New Body Style)
« Reply #17 on: January 19, 2015, 09:28:22 am »
What color is the wire

Offline DnStClr

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Re: Any TBI experts out there? (New Body Style)
« Reply #18 on: January 30, 2015, 07:55:38 pm »
engine coolant temp sensor pigtail?   No, after looking at Vile's schematics, the cts is on the front of the engine. 2nd guess is a tach  wiring pigtail.
« Last Edit: January 30, 2015, 08:36:34 pm by DnStClr »
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Offline Dr_Snooz

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Re: Any TBI experts out there? (New Body Style)
« Reply #19 on: January 30, 2015, 09:35:05 pm »
Shooting from the hip here but might be some sort of O2 sensor plug

It's funny you mention it. I broke the O2 sensor while installing the engine and the connector looks exactly the same. I reconnected it when I replaced it though.

What color is the wire

Purple. As near as I can tell.

2nd guess is a tach wiring pigtail.

Could be that. How would I find out for sure?
1989 Chevy Suburban V-2500, 5.7L, TH400

1990 Chevy C-3500 Ext. Cab, 7.4L, 3L80

2009 Chevy Silverado 1500 WT 4WD, 4.8L, 4L60

Offline Irish_Alley

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Re: Any TBI experts out there? (New Body Style)
« Reply #20 on: January 31, 2015, 12:58:13 am »


2nd guess is a tach wiring pigtail.

Could be that. How would I find out for sure?
on my 91 the connection is a male spade connection with a plastic covering and its on the drivers side of the intake coming off the coil i think
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Offline VileZambonie

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Re: Any TBI experts out there? (New Body Style)
« Reply #21 on: January 31, 2015, 10:28:14 am »
That connector is only used in 4WD applications. Being that it is a C series it doesn't connect to anything. The K series trucks have a 4wd harness which loops this to the EBCM for rear wheel anti-lock.
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Offline Dr_Snooz

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Re: Any TBI experts out there? (New Body Style)
« Reply #22 on: February 03, 2015, 09:44:02 pm »
I was wondering if it wasn't some vestigial thing like that. I've been driving it around up the big hills, pulling my trailer and it runs like old times.

Thank you all so very much!
1989 Chevy Suburban V-2500, 5.7L, TH400

1990 Chevy C-3500 Ext. Cab, 7.4L, 3L80

2009 Chevy Silverado 1500 WT 4WD, 4.8L, 4L60