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Topic: Fuel Pressure Issues, Have PSI Guage Readings on Last Page... (Read 3956 times) previous topic - next topic

Fuel Pressure Issues, Have PSI Guage Readings on Last Page...

Reply #30
The fuel pump can cause very strange problems. Right now my car has a bad fuel pump. I was betting millions that my problem was everything, LESS the fuel pump. My car started to the first crank, run in idle perfectly. Why in this world would be the fuel pump ? My car dies when you past 15 or 20 mph, and you can mash the gas pedal from a stop but your speed wouldnt be more than that. Even if you stop, put in Neutral, and rev the engine, you can get all the rpms the 3.8 can get, BUT NOT IN THE ROAD. I changed my plugs, wires, rotor, cap, battery, carburetor, another carburetor, tuned this carburetor, all the vaccum lines, and the car was the same.....well, i gave up, went to ask and advice to the mechanic and said, plain and simple "Get your fuel delivery system checked". And asked here, and the response was the same "Check your fuel pump". Now im saving a little money to get my fuel pump, because i dont have much money. It may take another few months. Check your fuel system....
1985 Mercury Cougar V6
1989 F-200 V8
1996 Explorer V6
2001 F-150

Fuel Pressure Issues, Have PSI Guage Readings on Last Page...

Reply #31
Ok guys, I finally was able to get a Fuel Pressure Guage kit at Harbor Freight for 8.99. Yes, I know, I'm an idiot. Ok here are the readings I got:

1) Key on, Engine Off: 0 PSI

2) Engine Cranking: PSI gradually builds up to 10 PSI and engine begins to start. This usually takes (with about 3 cranks of 3 seconds) 10 seconds of cranking altogether.

3) Engine Running at Idle: Pressure is 39 PSI constant.

4) Engine at 2000rpm: 39 PSI

5) Reving the Engine: PSI drops from 39 to 36 and then recovers back to 39.

6) Upon engine kill, PSI bleeds back down to zero.
Then the condition in #2 starts all over again.

7) I should also mention that I took off the Vaccum line from the top of the Pressure Regulator, and it made no difference when attempting to start the car. Also, the when Turning the key to On, I can hear the fuel pump turn on for a few seconds.

So, Fuel Pressure Regulator, or Pump? Something Else?
Again, I want to appologize for acting like such a whiney baby in my earlier statements. I just have very little patience, and was getting upset because I didn't think I could buy one of these kits so cheaply.
<---One must always remember to Remain cool, calm and collected when dealing with your fellow man, especially on the Internet....
-DMC24guy
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Fuel Pressure Issues, Have PSI Guage Readings on Last Page...

Reply #32
sounds like pump time

Fuel Pressure Issues, Have PSI Guage Readings on Last Page...

Reply #33
Quote
) Key on, Engine Off: 0 PSI


Looks like shes not priming, can you hear it prime when you turn the key?
[SIGPIC][/SIGPIC]


Fuel Pressure Issues, Have PSI Guage Readings on Last Page...

Reply #34
Quote
) Key on, Engine Off: 0 PSI


Looks like shes not priming, can you hear it prime when you turn the key?
[SIGPIC][/SIGPIC]


Fuel Pressure Issues, Have PSI Guage Readings on Last Page...

Reply #35
How long does it take to bleed back to 0 after shutting the engine off?
Long live the 4-eyes!  - '83 Tbird Turbo - '85 Marquis LTS - '86 LTD Wagon-  '81 Granada GL 2dr

Fuel Pressure Issues, Have PSI Guage Readings on Last Page...

Reply #36
When I turn the key on, I can hear the pump buzzing, and the bleedback to zero took about 3 seconds.
<---One must always remember to Remain cool, calm and collected when dealing with your fellow man, especially on the Internet....
-DMC24guy
[/SIZE]

Fuel Pressure Issues, Have PSI Guage Readings on Last Page...

Reply #37
Quote
and the bleedback to zero took about 3 seconds


wow thats fast, mine holds for a long time maybe 35min or so I never timed it.
[SIGPIC][/SIGPIC]


Fuel Pressure Issues, Have PSI Guage Readings on Last Page...

Reply #38
Well, thanks for the information. It's nice to know you have good pressure. So, what does that mean for me? I can hear the Pump Buzzing, yet there is no noticeable PSI on the guage when I turn the key to on. The fuel bleeds back after 3 seconds or so when I turn the key off. Pump? Regulator?
<---One must always remember to Remain cool, calm and collected when dealing with your fellow man, especially on the Internet....
-DMC24guy
[/SIZE]

Fuel Pressure Issues, Have PSI Guage Readings on Last Page...

Reply #39
Well smart ass, he was letting you know that that fast of a bleed down is not normal.  Since the FP looks normal when running, it might be a pump issue, but it could also be a regulator that is starting to go (might have a small pinhole leak).  A regulator is pretty cheap and a quick swap.  Get one, install it and run your test again.
Long live the 4-eyes!  - '83 Tbird Turbo - '85 Marquis LTS - '86 LTD Wagon-  '81 Granada GL 2dr

Fuel Pressure Issues, Have PSI Guage Readings on Last Page...

Reply #40
Quote
Well, thanks for the information. It's nice to know you have good pressure


well I was trying to help you

go out and buy a fuel pump, regulator, and a fuel filter than.
[SIGPIC][/SIGPIC]


 

Fuel Pressure Issues, Have PSI Guage Readings on Last Page...

Reply #41
You gotta realize people work during the day and everyone isn't sitting at home waiting for you type about the fuel pressure problem.

After I read your post about your bleedback to zero took about 3 seconds, I typed a quick reply cause my freaking phone was ringing and I had to go. But I took the time out to try and point you in the right direction...
[SIGPIC][/SIGPIC]


Fuel Pressure Issues, Have PSI Guage Readings on Last Page...

Reply #42
The fuel flow is from the fuel pump through the filter to the injectors then through the regulator and back to the tank.

The pump  is capable of pressures higher than 39 psi but the regulator allows gas to return to the tank at 39 psi. This maintains the pressure at 39 psi. (This part appears to be working)

When you turn off the engine the gas should remain trapped between the fuel pump check valve and the regulator. (THIS IS NOT WORKING)

Does the exhaust smoke when you start up? Injectors leaking.

Do you smell gas? Fuel line leaking.

Fuel Pressure Issues, Have PSI Guage Readings on Last Page...

Reply #43
Now that you know what the problem is you should crank it until it starts. Not the three seconds bursts.

If it turns out to be the fuel pump check valve, it could change from a problem to a nuisance that can be put up with.

Fuel Pressure Issues, Have PSI Guage Readings on Last Page...

Reply #44
Well, I gambled on a new Fuel Pump....and it paid off! The car starts right up, and runs great. I'm so happy. No more embarassment at Circle-K's and Wal-Mart parking lots. Now I can focus on what I really want to work on...the exhaust!

Thanks for all the help guys.
<---One must always remember to Remain cool, calm and collected when dealing with your fellow man, especially on the Internet....
-DMC24guy
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