fuel pressure

[1redjet]

OK I dropped the tank and it does not have a in tank pump. It just has the pickup and float. I changed the rubber lines because the had holes in them. Everything in the tank looked good. I am going to drop the tank again because I now have a leak around where the pickup goes in the tank. After I put it back together it still won't start. Since I don't have a in tank pump can I upgrade the inline pump?

[1redjet]

I am going to put the line coming off the pump in a gallon of gas and see if it will pick it up because I am still just getting air through my Schrader valve.

[kevinsranger]

you have an inline pump where? like an electrical one or a mechanical one that mounts to the timing cover? if you have a mechanical one bolted to the timing cover it wont make enough pressure to feed the fuel injection system, it would only be 8-12 psi and i think you need 30-40, not sure on the 4 cyl spec, i just know the 5.0 fuel injected usually want 35-42psi

[1redjet]

I believe it is running along the passengers side. It does not have a mechanical pump. The engine is from a 88 TC. I am going to try and get a look at the pump tomorrow.

[kevinsranger]

I believe it is running along the passengers side. It does not have a mechanical pump. The engine is from a 88 TC. I am going to try and get a look at the pump tomorrow.

have you ever had it running? its very possible the previous owner took the 88tc engine and swapped the timing cover and pump from the engine he was replacing. i would have thought if he installed it factory correct he would have swapped in a fuel injected mustang tank and in tank pump, maybe he figured a way to install an aftermarket rail pump.

if you do have a rail pump you need to find out what pump it is, it still may just be a lift pump for a carb style engine which would only put out a few psi pressure, or if it is the correct pressure rating, you need to find out it its a pusher or puller style pump, my friend had an old chevy pickup, and had fuel issues with his carb, found out the previous owner installed a puller style fuel pump back by the tank, he remounted the pump under the hood and it cleared up his fuel issues

[1redjet]

I may do a swap and go with a in tank pump. The previous owner said they had it running but it has been parked for several years.

[Jimmy2.3Mustang]

I'm sure someone will correct me if I'm wrong, but I was under the impression a later EFI tank from a Fox Mustang won't fit the body on the early Fox Mustangs. I know for a fact the Turbocoupe tank doesn't come anywhere close to fitting. When I faced the fuel system issue (converted from carb to EFI turbo) I considered the inline pump, but it was more expensive than getting a nice used tank assembly from an 86 GT the owner was converting to a fuel cell. However, with the specific tank issue, it'd probably be best to use a good external pump. As mentioned it needs to be capable of EFI pressures and volume, if the existing pump doesn't have markings that let you decode what it's intended for, you may want to just start from scratch on the fuel system. You would need the tank, pump, feed and return lines, a fuel pump relay, and wiring from the ECM to the pump.

With an external pump, they tend to be picky about how and where they're mounted. Most need to be in close proximity to the tank or they'll starve for fuel under some conditions.

[kevinsranger]

I may do a swap and go with a in tank pump. The previous owner said they had it running but it has been parked for several years.

i wonder if you have the same issue i believe im having with my 92, it sat for years and im having running issues, i have 39psi at the valve, and i believe the fuel that was inside the injectors themselves when the car was parked gummed up the injectors. i only ran it a few miles of very poor running, i was thinking if i drove it enough the fresh fuel would clean the injectors, but i think in the spring im gonna swap in a set of good used injectors from a running car

[1redjet]

I going to try and get under it tomorrow and see what pump it is.

[1redjet]

I couldn't stand waiting so I went out and crawled under the car. It has a Holley inline pump. I couldn't find numbers but it is black. I am going to look online and see if I can find one like it. If it is the one I am thinking it is it only holds 9 psi line pressure and is preset for 14 psi. Can anyone recommend a good external pump?

[1redjet]

How hard is it to swap to a 86 fuel setup?

[kevinsranger]

How hard is it to swap to a 86 fuel setup?

i would go for the 86 & up swap IF the tank fits, i just recently got a 79pc, and realized how different the 79-82 is from the rest, i always thought everything could be bolted in and swapped.

[1redjet]

I am pretty sure some of the newer tanks won't fit but thought someone said the 86 would. If I can get a good inline pump I may stay that route. They did a good install but pretty sure they just used the wrong pump.

[chads84svo]

Just keep what you have for a tank and swap out your inline fuel pump for a walbro inline 255 lph pump. That should get you zipn around town. Get it running before you start changing all kinds of stuff.

[1redjet]

Just keep what you have for a tank and swap out your inline fuel pump for a walbro inline 255 lph pump. That should get you zipn around town. Get it running before you start changing all kinds of stuff.

Yeah that sound like the easiest thing to do. I am pretty sure that holley is to small. Will I need a pressure regulator?

[chads84svo]

I have one on my svo (kirban) and i also have a preeure gauge on my fuel rail. I would do the in line pump and a adj FPR too so you can set the fuel pressure.

[1redjet]

I am going to do the pump, gauge and fpr. Probably be after Christmas before I can get it done. Hopefully that is the only problem. I worry about running into computer related issues.

[chads84svo]

Good luck with it..........we are all routing for you to get it running. Keep us posted. And Merry X Mas too.

[1redjet]

Thanks. I will hang in there until I get running. Can't wait to get it on the road. Hope you have a great Christmas also.

[Jimmy2.3Mustang]

Isn't there a Ford OEM application with an inline EFI fuel pump? Like a Ranger or F-150 or something like that? There should be a vast variety of external pumps available that would do the job but they're usually more expensive than the in tank pumps.

From what I remember to make the OEM EFI Fox Mustang tank fit the early cars, you'd have to cut out the trunk floor and weld in the trunk floor from a later car. As much of a pain in the ass as that would be, it'd allow you to use the tank, pump, fuel lines from a later car, and it'd practically bolt in.

The reason you may have read that an 86 tank fits earlier cars, is because the 87 up EFI cars have a different dash so the fuel level gauge sender is different. 86 and older cars need a 86 or older sender for the gauge to read correctly.

Old fuel injectors can cause all kinds of problems. My first set had two injectors that leaked where the plastic top mated to the steel housing. I got another used set and replaced the two leaky injectors and they ran OK for awhile. Now the idle is a bit rough, but I need to upgrade to bigger injectors anyway to support mods. I had a third set of good used injectors, that looked really good and came from a running/driving car. I sold them off and the buyer told me afterwards that they ran rough for him. I guess what I'm getting at is that 29 year old fuel injectors probably are nearly used up. Not even worth trying to buy a set of used injectors. But still, if there's no pressure at the rail the fuel isn't even at the injectors, so that wouldn't be the current problem.

[1redjet]

I am going to stick with a good inline pump add a new filter,regulator and gauge on the rail. Then go ahead and replace the injectors. Since I will be using a 255 pump should I upgrade the size of the injectors?

[Jimmy2.3Mustang]

On an otherwise stock engine, I'd leave the injectors be. I didn't really feel they were a problem until after changing to a Boport Stage 3 head and aftermarket cam. Try to get it running as clsoe to stock as you can so you can control potential variables.

[1redjet]

OK. I am just hoping the wired the computer properly and didn't just plug it on thinking it would work. I may need to find someone who has done this swap if I have to rewire it.

[chads84svo]

Im gonna pray for you tonight.........lol.

[1redjet]

Thanks I need it.