How to diagnose no fuel in the injector rail on a 97 TJ 4.0


TJ4Jim

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I took out the fuel pump tested it not working, not a single sound. So i disassembled the pump, clean everything with a ultra sonic parts cleaner. Dryed the pump off tested again no sound. So the pump is dead, today i searched for the whole assembly and found two types one for the 15 Gallon Tank and one for the 19 Gallon Tank. My question now is, will the 19 Gallon Pump Assembly fit my 15 Gallon tank, its way cheaper than the 15 Gallon Tank Assembly, what i dont understand....

Best regards Lennart
Go with the 19 gallon pump which is what you have, either way it will fit as the tanks are the same dimensions.
 

TJ4Jim

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Is there a issue with the sending unit maybe. That the amount isnt displayed right?

Best greetings
Nope not to worry, the 19 is the correct pump. Only the base models had the 15 gallon tank but you have a Sport.

My 99 had the 15 gallon pump and it's running the 19 gallon now.
 
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LennartfromAustria
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Nope not to worry, the 19 is the correct pump. Only the base models had the 15 gallon tank but you have a Sport.

My 99 had the 15 gallon pump and it's running the 19 gallon now.
That would be great 60 $ are nice to have, how can i check if i have a 19 gallon Tank? And i found out through my vin number that that I have a 15 Gallon Tank, now i am confused...
My Jeep is a TJ from 1997 4.0 Sport
 

TJ4Jim

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That would be great 60 $ are nice to have, how can i check if i have a 19 gallon Tank? And i found out through my vin number that that I have a 15 Gallon Tank, now i am confused...
My Jeep is a TJ from 1997 4.0 Sport
When the old pump is removed the circuit board for the gauge will be labeled on the bottom either 15 Gal or 19 gal. Again don't be concerned with the pump. I installed the 19 gallon pump in my so called 15 gallon tank 8 years ago. If necessary we can deal with the tank vent modification later.
 
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LennartfromAustria
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When the old pump is removed the circuit board for the gauge will be labeled on the bottom either 15 Gal or 19 gal. Again don't be concerned with the pump. I installed the 19 gallon pump in my so called 15 gallon tank 8 years ago. If necessary we can deal with the tank vent modification later.
Hey Jim,

Here are some pictures I took today, the vent tube and filler tube are quit long. There is a number on the fuel sending unit. But I don't know what it means.

Best regards Hugo

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TJ4Jim

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Hey Jim,

Here are some pictures I took today, the vent tube and filler tube are quit long. There is a number on the fuel sending unit. But I don't know what it means.

Best regards Hugo

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Looks to be the 15 gallon sized tank based on the part number so that gives you 2 options, either leave it as is or shorten the smaller vent tube about 3 inches with a utility knife. Either way your good with the 19 gallon pump.
 
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LennartfromAustria
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Looks to be the 15 gallon sized tank based on the part number so that gives you 2 options, either leave it as is or shorten the smaller vent tube about 3 inches with a utility knife. Either way your good with the 19 gallon pump.
Are there any risk's involved cutting the vent tube? And if I stick with the OEM Tank capacity and get the 19 Gallon Pump, what's going to happen? Is my fuel gauge going to be unusable.


Best regards Lennart
 

TJ4Jim

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Are there any risk's involved cutting the vent tube? And if I stick with the OEM Tank capacity and get the 19 Gallon Pump, what's going to happen? Is my fuel gauge going to be unusable.


Best regards Lennart
No risk whatsoever, cutting the tube back about 3 inches only duplicates what Jeep did to produce the 19 gallon capacity. A 19 gallon level sender will read the level correctly if the tube is shortened to allow the added vented space for additional fuel. If you leave it alone it will never show full on the gauge but will stay there a lot longer.

The 15 gallon gauge in a 19 tank the needle will stay on full a lot longer

That's pretty much it.

Both maternal grandparents born in Austria so I would not steer you wrong, Fritz and Wilhemina Kulin.
 
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LennartfromAustria
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No risk whatsoever, cutting the tube back about 3 inches only duplicates what Jeep did to produce the 19 gallon capacity. A 19 gallon level sender will read the level correctly if the tube is shortened to allow the added vented space for additional fuel. If you leave it alone it will never show full on the gauge but will stay there a lot longer.

The 15 gallon gauge in a 19 tank the needle will stay on full a lot longer

That's pretty much it.

Both maternal grandparents born in Austria so I would not steer you wrong, Fritz and Wilhemina Kulin.
Hey,
that's nice that your maternal grandparents are form Austria, my father went to high school in america as a exchange student.

I checked today with the local MOT Service and cutting the line would not be legal and if god forbid something happens, my insurance wouldn't cover me. To prevent this unlikely event from happening I ordered the 15 Gallon Fuel Pump Assembly. So In 2-3 Weeks it should arrive, i ordered a tool to remove the fuel line from the block to clean it out with air and some kind of cleaner, don't know jet which one too get. Maybe you know what kind of cleaner could work. While being under there I will address the rust and coat everything with fluid film especially the bolts which hold the skid plate.

My next task will be the brakes rear and front, do you know which brand is good. The rear drums are not that old probably 35.000 Miles but sitting for 10 Years and being 27 years old they are probably due.


Best greetings Lennart
 

qslim

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My next task will be the brakes rear and front, do you know which brand is good. The rear drums are not that old probably 35.000 Miles but sitting for 10 Years and being 27 years old they are probably due.
After sitting for that long you'll definitely want to flush all the fluid & inspect the calipers & wheel cylinders. I'd recommend starting a different thread just to keep everyone's advice organized & on track.
 
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LennartfromAustria
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After sitting for that long you'll definitely want to flush all the fluid & inspect the calipers & wheel cylinders. I'd recommend starting a different thread just to keep everyone's advice organized & on track.
How should I name the new thread?

Best regards Lennart