Author Topic: No power to choke after changing oil  (Read 2397 times)

Offline Stewart G Griffin

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No power to choke after changing oil
« on: October 19, 2019, 10:23:24 PM »
The choke doesn't work immediately after changing the oil.

1) i don't want to say that there's no power going to the choke although:
a) i can't feel any heat on the choke housing even after a few mins of driving
b) The chances of the choke failing immediately after changing the oil are astronomically improbable.  This is a fairly new choke.

So, i'm going to initially conclude that there is no power going to the choke at this point.

2) The fuse appears good.

3) Now i did wipe some wires "around the area" of the oil pressure sensor very vigorously----because i spilled oil on them when removing the filter.   i'm thinking it has something to do with this?

Could anyone point me to a wiring diagram of the choke circuit or even draw one?

i will probably post pics tomorrow as it is dark (and cold) now.

Offline DanMcG

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Re: No power to choke after changing oil
« Reply #1 on: October 20, 2019, 03:35:17 AM »
I'd start with a test light and see if there's power to the choke.
It should get it's power from the oil pressure switch.
« Last Edit: October 20, 2019, 03:43:17 AM by DanMcG »

Online bd

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Re: No power to choke after changing oil
« Reply #2 on: October 20, 2019, 11:43:15 AM »
For a general explanation, see GM Electric Choke Operation.

Study the wiring diagram located in the Technical Forum that pertains to your particular truck.
Rich
It's difficult to know just how much you don't know until you know it.
In other words... if people learn by making mistakes, by now I should know just about everything!!!
87 R10 Silverado Fleetside 355 MPFI 700R4 3.42 Locker (aka Rusty, aka Mater)

Offline Stewart G Griffin

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Re: No power to choke after changing oil
« Reply #3 on: October 21, 2019, 01:17:07 PM »
False alarm:  Sorry:

i failed to include that, in addition to changing the oil, i also changed the fuel filter to the electric pump and changed the air filter.   This is one of those open air assemblies.

i think what happened was in my rush to get it all done, i tightened the air filter assembly against the choke rod causing it to bind (there is some play with some of these aftermarket air filter assemblies on the top of the quadrajet.   Not enough play where air can leak in under the assembly, but some side-to-side play)  i initially plopped it on there and tightened it down because i was in a "get it done" mood.

There is now, apparently, power going to the choke as it did open while driving after i adjusted the AF housing.   Also, the coil is warm/hot to the touch after a few mins.   i think the first time i felt it i few days ago i was in a hurry to get to work; i did not remember clearly whether the coil was truly warm or it was colder outside, or i just didn't wait long enough to let it heat up?   Thus, "concluding" that there was no power going to the choke.

Sometimes not rushing and procrastination is a good thing?
« Last Edit: October 21, 2019, 01:26:03 PM by Stewart G Griffin »

Offline Stewart G Griffin

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Re: No power to choke after changing oil
« Reply #4 on: October 21, 2019, 01:32:29 PM »
i just re-read my original post.

i stated that i could not feel any heat on choke housing.   i noticed today, while trying to figure out the problem, that the choke coil (the black circle thing) DOES radiate heat while the actual housing (the aluminum/metal part) did not (does not?) IF  the choke is working properly.

This may have led me to believe that there was no power going to the choke because i touched the housing and it felt cold, while all along power WAS in fact going to the choke?

Offline fitz

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Re: No power to choke after changing oil
« Reply #5 on: October 22, 2019, 03:52:55 AM »
Glad you got it figured out.

Offline Stewart G Griffin

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Re: No power to choke after changing oil
« Reply #6 on: October 24, 2019, 02:35:38 PM »
Glad you got it figured out.

Cars is something you can't rush (although those pit stop guys seem to have it down ;D);   They require care and precision.

Sometimes i get into a "Type  A, get it done now, now, now!  Fast, fast fast!" mode and this just doesn't work with cars.