[Schurkey]

Originally Posted by GP67

Cheap azz GM tin covering that pump.

It's not tin, it's steel. Cutting the body for an access hole was not a wise move.

It's one piece with no access hole to prevent fumes, and liquid fuel from entering the passenger compartment in a collision.

Remember the Pinto? Tank ruptures, no sheetmetal between tank and passenger compartment. Passengers get basted in gasoline gravy, then burn to death. They stopped screaming when their vocal cords charred.

Don't let that be you. That hole has to not only be re-sealed, it has to be sealed so well and so strongly, that the seal isn't compromised when the body buckles in a crash.

[GP67]

It's perfectly OK for a grown mans eyes to sweat....

The car is running.
Been sitting here the last 30 minutes trying to come up with the right words to express my appreciation to everyone who helped me, I'm really beside myself to think that people I've never seen nor spoken a word to in my life took the time, and alot of time at that, to hang with me so long in solving this problem.
All of you, everyone who helped no matter how big or small contributed to solving this. You all have my heartfelt thanks.

The problem was found to be the GRAY wire. I posted a pic that shows where I tied the wires back together in the lower portion of the pic.
How it happened:
I was going to take further readings as instructed eliminating the connector for a straight test at the pump. When I picked up the wiring harness where the new wires from the pump get the new connectors to existing wires during new FP installation GREENISH BLUE powder dropped out of the harness. (corrosion)
I peeled back the tape and found the GRAY wire was apart.
It appears the connection was burnt. I don't know why it appears burnt though, any ideas? (and I'm listening because ALL your ideas have been better than mine)....
I stripped back the two GRAY wires, made a new connection, and she fired right up!

["QUICK-SILVER"]

Originally Posted by GP67

GREENISH BLUE powder dropped out of the harness. (corrosion)
I peeled back the tape and found the GRAY wire was apart.
It appears the connection was burnt. I don't know why it appears burnt though, any ideas?!

When wires, terminals, connections, etc., get corroded it causes resistance. Resistance makes things heat up fast. As wires wear away they get smaller and smaller till nothing is left. So when you get down to a single strand or two, they'll actually turn red and melt.

Congrats on figuring it out!
Clay

PS Shurkey mentioned a few times about the poor quality of wiring on these cars. They just don't build um like they use to.

[GP67]

Originally Posted by "QUICK-SILVER"

PS Shurkey mentioned a few times about the poor quality of wiring on these cars. They just don't build um like they use to.

Yes he did. To tell ya, some of you guys knowledge makes me think you're engineers with your line of thinking.
I like to work on cars. I learned the first time I did the fuel pump and now this time around I learned the electrical aspect.

I know this isn't a Pontiac but maybe someone here owns one of these Mercury Grand Marquis? I needed a big car because I like a V8 and i got this one owner car with 68,000 original miles for under $1000....

The AC is blowing warm (I knew when purchased), The AC compressor clutch is not engaging when I select AC. The fuse is good. I have looked for a wiring schematic online with no luck. Checked out Ford forums with no luck.

I imagine there's a way to bypass the relay and jumper it to test if the clutch will engage or if it's dead.
I don't know if the refridgerant is low either, but thought I'd try to make the clutch engage rather than put refrigerant in it only to find out the compressor is shot.

Thanks

[TedRamAirII]

Find the Accumulator, that big silver can, about 4" in diameter under the hood, on the right side. There will be a switch there, unplug the switch and connect the 2 wires together with the A/C switched ON, if the compressor starts spinning, the r134 (refridgerent) is low, and not enough pressure to turn the switch on. Now WHERE the leak is is the question. These older models, the compressor is most likely the leak, unless you see any oily areas usually near a hose or anywhere near a o-ring seal. If its not obvious where the leak is, I like to charge it, add U.V. dye and use it a few weeks, then look the system over for the trace of dye. You may need to go to a A/C shop that can do this, as I dont think you will have the tools to do it. No way to tell if the compressor is "shot" unless you get a charge in it and check pressures.

[GP67]

Thanks.
I will do the wiring of the switch part as instructed.
If Autozone has the loaner tools to do this if it gets more involved I will get them.

[GP67]

Another Grand am question.
The service engine soon light is on. Had it scanned and was told it's the knock sensor. Been reading up on the symptoms of a bad knock sensor and the car is exhibiting none of the symptoms I've read about. The car is running fine. Is there a way to test it to be sure it's the knock sensor?
Thanks.

[Schurkey]

Clear the code, see if it comes back.

[GP67]

Thankfully I did cut the hole to get to the fuel pump.
The car wouldn't start so I went to the panel and found 2 connectors burned.
The attached pic shows a wirenut I just put on and it fired right up, HOWEVER, the wires from the connector on the BODY is thinner than the wire ON THE NEW HARNESS.
The WHITE STRIPED wire in the pic shows this as well.
IS this why I'm having this trouble?
WHY are the NEW harness wires thicker?

I was told the NEW wiring harness are GM spec..

Thanks guys. I don't want to keep doing this if it's going to continue to be a problem.

[Schurkey]

Originally Posted by GP67

Thankfully I did cut the hole to get to the fuel pump.
The car wouldn't start so I went to the panel and found 2 connectors burned.

WHY did the connectors burn? Too much amperage? Too much resistance? Something else?

You NEED to figure this out.

Originally Posted by GP67

The attached pic shows a wirenut I just put on

That is a temporary measure, just for testing...right? It will be a corroding mess long-term.

Originally Posted by GP67

and it fired right up, HOWEVER, the wires from the connector on the BODY is thinner than the wire ON THE NEW HARNESS.
The WHITE STRIPED wire in the pic shows this as well.
IS this why I'm having this trouble?
WHY are the NEW harness wires thicker?

I was told the NEW wiring harness are GM spec..

When you say the "new harness wires are thicker" or the "body wires are thinner" are you differentiating between the actual wire gauge--the copper conductor--versus the wall thickness of the insulation (which means essentially nothing.)

The same size copper conductor could be inside the thicker insulation.

[GP67]

"When you say the "new harness wires are thicker" or the "body wires are thinner" are you differentiating between the actual wire gauge--the copper conductor--versus the wall thickness of the insulation (which means essentially nothing.)

The same size copper conductor could be inside the thicker insulation.[/QUOTE]

The new harness wire is considerably larger than the body wire. It is stranded copper inside a jacket.
The body wire has say 6 strands of thib copper wire.
The harness wire has more strands and they are thicker copper strands.
It is definitely 2 different gauges.
I don't know what gauge GM used, or what gauge the harness wires are because none of the jackets have gauge markings.

[GP67]

I found GM tech note:

" Tech Note- When replacing the fuel pump harness connector be sure to remove as much of the old wiring as possible. For example, if the connector had a poor connection this would create a resistance problem resulting in heat. This excessive heat melts the wiring insulation allowing moisture to enter and corrode the wiring, resulting in future problems."

THIS SOUNDS LIKE A KNOWN PROBLEM.

[GP67]

I'd never believe it but it's been 68 days and my fuel pump died yet again. I took the car to a trusted mechanic I know about the prior wiring issue and all went well with that. So anyway, I went to start the car this morning and nothing happening. removed my new fuel pump hatch to check the wiring to be sure and everything is fine. No corrosion, nothing out of the ordinary. Swapped out the under-hood relay and of course I still got nothing. So, I'm about to try the hammer trick and if it's a no go I will replace the pump with a new one I already have.
what a trip.

[Schurkey]

Do you have power to the pump? Does the pump have a good ground?

(I mean NOW, not the last time you checked, 68 days ago.)

[GP67]

Originally Posted by Schurkey

Do you have power to the pump? Does the pump have a good ground?

(I mean NOW, not the last time you checked, 68 days ago.)

Good call Shurkey.
I just re-read this entire post a couple of times for a refresher and will be on this project first thing in the morning.

And to boot, I swapped pumps earlier today and it did not run.

Not that this has anything to do with the pump but, I got a new inspection sticker yesterday, drove it home, parked it, and now it doesn't run.
It's just too comical.

[GP67]

It was a fuse. Under-hood... #48... 15 amp.
Fuse was no good. Replaced.

First time this has happened. Should I be concerned?
If so, What should I be testing?
Thanks

[Schurkey]

Access hole or not, I hate seeing a guy change fuel pumps when the real problem is a popped fuse. Diagnose FIRST, replace LAST.

Fuse pops once, I don't give it a second thought. Fuse pops twice...time to dig into the real problem.

If that fuse pops again, you'll be looking at the ENTIRE FUEL PUMP WIRE HARNESS checking for bare spots that could ground, and you'll be testing the fuel pump amperage draw, which goes back to Post #4 of this thread.

[GP67]

Thanks Shurkey. I'll be keeping an eye on it.
Hopefully this subject will finally be put to bed once and for all.
Have a great day!

[GP67]

Another set of questions.

Went out to start the car and the fuel pump didn't prime, no blown fuse, I checked, had the wife turn the key while I held down on the FP relay and it started. Took my finger off and it died. I noticed while applying pressure to the relay the car runs smoother than it has been.
The two legs at the front of the relay where they insert into the slots are very loose, I spread the pins a bit and still they are loose. I'm thinking when I was using the multimeter previously I may have spread the slots a bit too far causing this loose pin situation. Currently I have positioned a piece of cardboard under the cover to keep pressure downward on the relay and it appears to be working.

Is there a way I can fix the pin holder so the relay will fit tight again?
Also, can the relay being loose cause the FP fuse to burn out? (even though it didn't this time)
Thanks

[HWYSTR455]

Replace the terminals on the relay socket, and make sure the relay has good legs on it. Ues a good crimper or solder them too.

.