Ranger Fuel System Woes

[ltbenji]

And I also need to check the volts at the tank pump

 

[ltbenji]

I was not able to check the volts at the tank pump....couldn't find a ground. But the high and low pressure pumps share hot wire I would assume it is getting enough volts.

On a different note, I primed the pumps again and watch the gauge and the pressure started dropping. From 27 to 20 it only took a few seconds but it kept slowly but consistently dropping. Yesterday I did notice that the return line had been bent all the way around so I am wondering if pinholes would cause this problem or if it is the previously mentioned check valve in the high pressure pump. Any ideas?

And both pumps are Airtex brand...has anyone heard of or had problems with this brand?

 

[RonD]

Holes in the return line would leak fuel but not pressure, FPR and check valve hold pressure when engine is off.

Not sure if there is a check valve on the low pressure pump in the tank, but that shouldn't matter since the high pressure pump would be the more important check valve.

So you have:
Tank/low pressure pump-------high pressure pump(check valve)-----fuel rail(injectors)-----FPR----return line---tank

The 30psi fuel pressure is between the high pressure pump and FPR, so a leaking seal at either end would cause pressure to drop.
A stuck open injector would as well.

You could remove the return line, put a towel under it and turn on the key(NOT ENGINE!), with no vacuum the FPR should be closed and no fuel should come out, shut off key and watch for leaking fuel.

 

[ltbenji]

And checking for leaking fuel this way would tell me if what part is bad?

 

[ltbenji]

Got a replacement high pressure pump and installed it.
Primes to 38 psi every time.

I'm assuming that's close enough to 40.

Let me know if I'm wrong.

 

[adsm08]

38 sounds good enough to me. It only needs 35 to run.

 

[ltbenji]

Many thanks guys. My truck is back up and running. Next project is to set the timing correctly so it doesn't turn heads when it starts. For another weekend.

 

[joenorthcarolina]

Shot outs to everyone in this thread.

Special Thanks to "RodD" for such great information.

My problem was the Relay Sockets and possibly a relay. I only had 10v at the inertia switch before the repair. I'm not sure what it is currently but some junk yard sockets/relays fixed things good. Funny thing, all the Rangers in the junk yard had these relays and sockets missing. Must be a common problem...lol

 

[Mark_88]

Shot outs to everyone in this thread.

Special Thanks to "RodD" for such great information.

My problem was the Relay Sockets and possibly a relay. I only had 10v at the inertia switch before the repair. I'm not sure what it is currently but some junk yard sockets/relays fixed things good. Funny thing, all the Rangers in the junk yard had these relays and sockets missing. Must be a common problem...lol

Congrats for reading and learning...and, Yeah, RonD explains things that I've never understood before...maybe we should make him a Tech...

And about the junkyards...the relays are actually an easy thing to slip into your pocket...lol

I'd have to admit to putting a few things in the bottom of my tool box that wouldn't be missed...nothing major that I wouldn't otherwise pay for, but things like plastic clips and such...I can't justify it (theft), but I'm pretty sure the junkyards have made way more than they paid for the scrap cars that come into their yards.

And on that note, I happened to be in one today that is usually pretty clean...today the entire yard was stacked three cars high in every inch of the yard...when I asked what was going on, the guy behind the counter said something about taking in 100 vehicles a day......where do they get them from...maybe a new contract with the police...

But I have a funny feeling it is the price of metal has gone way down and they are stockpiling for when it goes up again...someone correct me if I'm wrong...