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87 Grand Marquis Help

Blue-Truck-Nut97

crank polisher
583
20
Definitely an advantage. The difference is the alcohol in the gas. Alcohol, or ethanol rather, fuel eats a tank up quick. That car was parked about 12 years ago with gas from Albuquerque.

I've got trucks in the yard that were parked for 30 years, and are clean enough to pour gas in and drive away.

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Well, I decided to pass on the car. I had a go at it today. Once I got the car raised up on jack stands and was able to get a better look underneath I was able to see some things I wasn't real happy with. The AIR Pump had already been deleted with the pipes running to the cats already cut and folded over. Additionally, no rust on the car itself, but the exhaust system btwn the cats and muffler has some holes in it.
Putting coolant in it showed leaks from the water pump and the rad drain cock. I wanted to change that stuff out anyway, but was hoping they'd at least get me home first.
I ran the borescope into the tank, and it didn't look terrible...from what I could see of it anyway. And, all dry. No old fuel in it. I put 8 gals in.
After changing the oil I tried to fire it up. Cranked fine but no fuel delivery to the rail. Pump's not running at all. Checked to make sure the inertia switch wasn't tripped but it was good.
I had all the tools in the world with me EXCEPT my multimeter as my dear brother borrowed it a month ago and keeps leaving it at his girlfriend's house, so I wasn't able to really troubleshoot any electrical wiring.
I did find the tank, and the fuel pump is actually pretty easily accessible from under the car, and I considered changing it out; but by that point I had found a number of wires and vacuum lines under the hood that had been cut (presumably by whomever deleted the AIR pump) so the car was starting to look like someone else's headache.
I pumped up the tires so it would at least roll, and told my buddy to toss it on to craigslist for $800 or so.
 

Blue-Truck-Nut97

crank polisher
583
20
Well I'm sad to hear it didn't work out. But that's smart on your part recognizing it's something you don't want to mess with, I commend you for that.

Just thinking out loud here, I wonder if the cars have the same fuel pump test plug under the hood. Never messed with a car with efi of that era.

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dustybumpers

don't play well w others
Same rail and setup as trucks. Different plenum, throttle body

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Not sure what you mean by "test plug" but it did have a schrader valve in the fuel rail right next to the distributor. So I was able to screw in my fuel pressure gauge to it and see the reading. Never came off of zero.:rotz:
 

Blue-Truck-Nut97

crank polisher
583
20
Does it have the single wire for the pump test in the plastic protector as the trucks?
Same low pressure tank pump/high pressure pump in the frame?

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Blue-Truck-Nut97

crank polisher
583
20
Not sure what you mean by "test plug" but it did have a schrader valve in the fuel rail right next to the distributor. So I was able to screw in my fuel pressure gauge to it and see the reading. Never came off of zero.:rotz:
Where the OBD 1 test port is under the hood there is a grey single wire female spade connector, if you power it it powers the pump, used for a pressure test, on the trucks anyway, we'll see what Dustybumpers says.....

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dustybumpers

don't play well w others
Has same obd1 test port. Yes, has both pumps, so it probably has a burnt fusible link off the solenoid

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Wait...pump in frame too? Test port? ug. Sounds like I was a bit out of my depth anyway. Like I said initially, 80's American, and OBD-I, is largely a mystery to me. But this wasn't the car to learn on IMO. Too many hands had already been on it it seems. Deleting stuff.
Hopefully something else of that era will come along eventually that I'll feel more comfortable getting my feet wet with.
I've brought a few cars back from the dead and it's a great feeling when it works out as I'm sure you know. Gotta pick yer battles though.
Thanks for the time and effort and advice with this one guys! Even though it didn't work out, I learned a lot from you two.
 

dustybumpers

don't play well w others
Pump in the tank is a lift pump, one in the frame is the high pressure pump.
1990 they went to high pressure pump in the tank, with a check valve to make sure the fuel returned to the tank it came from. Not a problem in the cars, but trucks had 2 tanks, and when the check valve fails it fills the other tank. Sometimes causing it to overflow.


There was a recall that added a external check valve. If you see one of those, snatch it, they bring a pretty good price now, as ford timed out the recall.

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