Let's, please, get a TBI car running again, if you don't mind....

[Noek]

I did not make fun of you but you were telling him details on where to find a test plug on a k5. Just pointed out that it's a tbi, and all tbi technology applies but not specific locations from a k5.
I was very careful with my post.

Dude, I wasn't telling him anything about where to find a test plug, my first post I was simply explaining my frustration with my experience with a similar year TBI system...never mind the fact that we are in a CK5 forum, but all of that aside, it was basically what I went through with a like early model TBI system.

My second post was in response to vandelays response to me, again I was talking about MY experience and what I went through.

Maybe I should delete my irrelevant posts so only you can have an opinion and everyone can just listen to your awesome experience and advice.

 

[rampage]

Dude, I wasn't telling him anything about where to find a test plug, my first post I was simply explaining my frustration with my experience with a similar year TBI system...never mind the fact that we are in a CK5 forum, but all of that aside, it was basically what I went through with a like early model TBI system.

My second post was in response to vandelays response to me, again I was talking about MY experience and what I went through.

Maybe I should delete my irrelevant posts so only you can have an opinion and everyone can just listen to your awesome experience and advice.

 

[dyeager535]

Connector looks melted to me, but the back side appears to be the tar-like substance GM sealed connectors with back then.

GM had a penchant for using undersized connectors/wiring in some cases (heater blower comes to mind) which lead to melted connectors.

Just focus on getting the pump to run. Ground and 12V. You'll feel you are making progress if you can get it to run, or determine that it doesn't actually work.

 

[vandelay industries]

1) First off, i appreciate ALL the input here, so i feel there's no need for us to get pissy at this point; On the subject of different TBI applications, based on my limited research, knowledge and hunches, ALL the unibody compact and/or FWD systems seem pretty similar including camaro/firebird as far as where stuff is located. While the monte carlo/impala etc. are more similar to the trucks, i think. But, as we know, ALL TBI is basically pretty similar.

2) i am working at looking at the pump right now. i can't really get on it whole-hog because i'm busy with work. My whole situation is F'd up with having no transportation of my own.

 

[vandelay industries]

Pump doesn't run after putting power directly to the pigtail.

i couldn't do the OHMs test at the pigtail because i couldn't find a good ground. There is more corrosion under there than i thought. i thought newer cars wouldn't have corrosion problems, but this isn't true. (We use salt here on the roads, in case you are from cal, fl or tx....etc.)

 

[dyeager535]

Pump doesn't run after putting power directly to the pigtail.

i couldn't do the OHMs test at the pigtail because i couldn't find a good ground. There is more corrosion under there than i thought. i thought newer cars wouldn't have corrosion problems, but this isn't true. (We use salt here on the roads, in case you are from cal, fl or tx....etc.)

Your part of the country is pretty well not a consideration for me to move to, for that reason alone. Although the idiots over here seem to have started using it as well, in certain places.

With a lot of rust, connections to any steel (typically the ground) is going to be the primary concern. Only two things you really need to know for testing the pump in the tank...is the ground good, and is there 12V when there should be? If both of those are met, and it doesn't run, obviously the pump or in-tank wiring is bad.

Is there access to the sending unit through the trunk? I want to think that some of the GM vehicles actually came with an access port back there, unlike the K5's.

 

[bp71k5]

Pump doesn't run after putting power directly to the pigtail.

i couldn't do the OHMs test at the pigtail because i couldn't find a good ground. There is more corrosion under there than i thought. i thought newer cars wouldn't have corrosion problems, but this isn't true. (We use salt here on the roads, in case you are from cal, fl or tx....etc.)

did you check the actual relay is good or not? (not just the socket wires)

 

[rampage]

Pump doesn't run after putting power directly to the pigtail.

i couldn't do the OHMs test at the pigtail because i couldn't find a good ground. There is more corrosion under there than i thought. i thought newer cars wouldn't have corrosion problems, but this isn't true. (We use salt here on the roads, in case you are from cal, fl or tx....etc.)

In one of my previous posts I told you how to get a good ground. If you couldn’t get a good ground to measure the resistance then you can’t get a good ground to test when you apply voltage. Scrape down to bare metal on the tank, preferably at the lip of the seam in the middle of the tank. The tank is electrically isolated from the rest of the vehicle due to the anti-squeak pads on the tank straps and rubber hoses, hence the ground strap from the tank to frame. So grey wire (if it’s set up the same as a Blazer) gets 12V and ground is bare metal on the tank.

 

[vandelay industries]

Your part of the country is pretty well not a consideration for me to move to, for that reason alone. Although the idiots over here seem to have started using it as well, in certain places.

With a lot of rust, connections to any steel (typically the ground) is going to be the primary concern. Only two things you really need to know for testing the pump in the tank...is the ground good, and is there 12V when there should be? If both of those are met, and it doesn't run, obviously the pump or in-tank wiring is bad.

Is there access to the sending unit through the trunk? I want to think that some of the GM vehicles actually came with an access port back there, unlike the K5's.

No. i plan on making an access hole though. Also, at this point there is no diff in the way, so dropping the tank the conventional way is not going to be too difficult either----ASSuming the bolts aren't rusted........

did you check the actual relay is good or not? (not just the socket wires)

No. Will.

In one of my previous posts I told you how to get a good ground. If you couldn’t get a good ground to measure the resistance then you can’t get a good ground to test when you apply voltage. Scrape down to bare metal on the tank, preferably at the lip of the seam in the middle of the tank. The tank is electrically isolated from the rest of the vehicle due to the anti-squeak pads on the tank straps and rubber hoses, hence the ground strap from the tank to frame. So grey wire (if it’s set up the same as a Blazer) gets 12V and ground is bare metal on the tank.

You did. i forgot. But can't the battery negative post be the ground? That's how i tested power to pump.

The other thing i don't get is if the tank is isolated from the rest of the car, and let's ASSume the ground strap from the tank-to-car is no good. Then how can the tank be grounded?

 

[rampage]

You did. i forgot. But can't the battery negative post be the ground? That's how i tested power to pump.

The other thing i don't get is if the tank is isolated from the rest of the car, and let's ASSume the ground strap from the tank-to-car is no good. Then how can the tank be grounded?

One of two things is happening here:
1) We have a miscommunication
2) You asked to have it explained to you like we were talking to a 5 year old and I did my best, but then you didn't follow the directions, much like a 5 year old would do.

I'm hoping it's the former.

I'll start off with answering your questions. Yes, the negative can be the battery post, but what did you connect the negative battery post to? If you connected it directly to the tank as I described then all is good. If you connected it to the frame then that's questionable since we don't know the condition of the small wire (ground wire) that goes from the frame to the tank. If that wire is broken inside the insulation or making a poor connection then electricity won't flow. Is that small wire even there? Remember, not only do you need positive voltage but you need another connection for the current to flow back to the battery which would be the ground wire. The ground wire is just as important as the positive wire.

Let me give you a simple circuit, a battery and a light bulb. Connect a wire from the positive battery post to one end of the light bulb. The light bulb won't illuminate since there is not a return path for the electricity to flow - this is known as an open circuit. Now connect the negative post of the battery (ground) to the other side of the light bulb. This completes the circuit and current can now flow back to the battery and illuminate the bulb.

The fuel pump is no different than this circuit, just replace the light bulb with the motor in the pump. The motor is simply a long thin strand of wire wrapped into many coils that rotates between magnets. Hope that's not too confusing for you, if so then just think of it as a very long wire.

The resistance of the motor (the very long wire) is measured using the same connections. One of the leads of your meter goes to the grey wire and the other lead goes to the bare metal on the tank - doesn't matter which lead of your meter goes to which connection. You should get a reading of maybe 10 to 50 ohms or something small like that.

So in summary, positive wire goes to grey wire, Get down to bare metal on the tank. Negative side of battery post goes to bare metal on tank. I've done this before on my Blazer and a small 9V battery - positive to grey wire and ground to bare metal on tank and the fuel pump runs so I know that the ground for the fuel pump is connected directly to the tank. It's just like how they use the frame and body of the truck as ground, but since it is electrically isolated as I described earlier, a small ground wire goes from the tank to the frame.

If any of this doesn't make sense (and don't worry if it doesn't since I know electricity is mysterious to most) then I'll try to explain it like I'm talking to a 2 year old.