Crown Vic fuel problem
#1
11-15-2014, 07:19 PM
Crown Vic fuel problem
Here we go again! Last winter I posted about my 01 P74's no- start condition in cold weather. I eventually got a fuel pressure gauge, and the output was within specs on every phase of my tests. The car started and ran fine all spring and summer.
It was a cold night last night. My wife had filled the tank last night then came home and parked.
Wellll.....Car would not start this morning. I took off the rail valve cap and a small chunk of ice popped out. I depressed the valve stem, and a little gas came out, then stopped. I hooked up the pressure gauge, turned on the key....NO pressure. I hooked up an electric heater and placed it under the fuel line area; no results. I jacked the car up, got my heat gun, and heated the fuel filter, then the area where the lines come out of the tank, for about 15 minutes.
PRESTO! fuel pressure and normal start afterwards. I let it idle and rechecked all the pressure phases; they were in spec, same as last season. Took my 03 P71 up to the new Advance Auto they built about 1 mile from my house (good!); bought some "Heet", put a bottle in each car. I rechecked the 01 throughout today, and, one time it stumbled a few secs after start; the pressure was about 25 #, then jumped to 32 # very quick. (Guess there was still a "slug" of ice in the line somewhere?) No further trouble. I drove the 01 around some tonight, with the gauge still on it. Pressures stayed where specs say they should. So, I'll see what happens in the morning.
I just can't figure why ice is affecting this one car so much, especially since the pressures are correct. The pressure has not lessened any since last season. But if I recall, once I started using "Heet" or some deicer in the tank last season, I had no other problems. I had forgotten last season's trouble, since it never happened again until last night. Guess it is just water freezing somewhere in the fuel pump/ filter area?? BTW, I changed the filter last season; it was not restricted very much when I replaced it.
Now that this long "western" is over...any ideas from you folks?
It was a cold night last night. My wife had filled the tank last night then came home and parked.
Wellll.....Car would not start this morning. I took off the rail valve cap and a small chunk of ice popped out. I depressed the valve stem, and a little gas came out, then stopped. I hooked up the pressure gauge, turned on the key....NO pressure. I hooked up an electric heater and placed it under the fuel line area; no results. I jacked the car up, got my heat gun, and heated the fuel filter, then the area where the lines come out of the tank, for about 15 minutes.
PRESTO! fuel pressure and normal start afterwards. I let it idle and rechecked all the pressure phases; they were in spec, same as last season. Took my 03 P71 up to the new Advance Auto they built about 1 mile from my house (good!); bought some "Heet", put a bottle in each car. I rechecked the 01 throughout today, and, one time it stumbled a few secs after start; the pressure was about 25 #, then jumped to 32 # very quick. (Guess there was still a "slug" of ice in the line somewhere?) No further trouble. I drove the 01 around some tonight, with the gauge still on it. Pressures stayed where specs say they should. So, I'll see what happens in the morning.
I just can't figure why ice is affecting this one car so much, especially since the pressures are correct. The pressure has not lessened any since last season. But if I recall, once I started using "Heet" or some deicer in the tank last season, I had no other problems. I had forgotten last season's trouble, since it never happened again until last night. Guess it is just water freezing somewhere in the fuel pump/ filter area?? BTW, I changed the filter last season; it was not restricted very much when I replaced it.
Now that this long "western" is over...any ideas from you folks?
#2
11-16-2014, 07:23 AM
You should get a few replies on this.
One of the most common reasons for moisture accumulating in the fuel tank is running the tank below half most of the time. Condensation from heating and cooling pull in moisture that builds up and when enough gets in there it starts going into the filter and lines. Another possibility could be where you are buying your fuel. They may have a problem with water getting into their tanks.
In the fall and winter it doesn't hurt to add a bottle of HEET every other tankfull especially since you are aware of the problem. Make sure you use the HEET containing Isopropyl alcohol and not methanol.
One of the most common reasons for moisture accumulating in the fuel tank is running the tank below half most of the time. Condensation from heating and cooling pull in moisture that builds up and when enough gets in there it starts going into the filter and lines. Another possibility could be where you are buying your fuel. They may have a problem with water getting into their tanks.
In the fall and winter it doesn't hurt to add a bottle of HEET every other tankfull especially since you are aware of the problem. Make sure you use the HEET containing Isopropyl alcohol and not methanol.
#4
11-16-2014, 02:38 PM
You should get a few replies on this.
One of the most common reasons for moisture accumulating in the fuel tank is running the tank below half most of the time. Condensation from heating and cooling pull in moisture that builds up and when enough gets in there it starts going into the filter and lines. Another possibility could be where you are buying your fuel. They may have a problem with water getting into their tanks.
In the fall and winter it doesn't hurt to add a bottle of HEET every other tankfull especially since you are aware of the problem. Make sure you use the HEET containing Isopropyl alcohol and not methanol.
One of the most common reasons for moisture accumulating in the fuel tank is running the tank below half most of the time. Condensation from heating and cooling pull in moisture that builds up and when enough gets in there it starts going into the filter and lines. Another possibility could be where you are buying your fuel. They may have a problem with water getting into their tanks.
In the fall and winter it doesn't hurt to add a bottle of HEET every other tankfull especially since you are aware of the problem. Make sure you use the HEET containing Isopropyl alcohol and not methanol.
Last edited by littleman; 11-16-2014 at 02:40 PM.
#6
11-17-2014, 07:48 PM
I did have one quirk Sun afternoon; I removed the gauge, and the attaching nut is not as free turning as it should be. As I unscrewed it fast as I could, a decent amount of gas and bubbles spewed out. I figured that dropped the pressure and maybe let an air pocket in the rail, so I turned the key on for a couple seconds before cranking. The car did start, but sputtered and coughed, so I turned it off and restarted it. It started and ran fine from then on. It wasn't really cold last night. I started it this afternoon and let it idle for about 20 minutes with no problems. NOW...tonight it's suppose to get around 20 with brisk wind chill on top of that; suppose to get to 12-15 Tues night, so that will give it a good test. I have driven it some, and it runs fine; plenty of power and no miss or other malfunction. This one has the factory Performance/ Handling Package, but I had the rear air bags replaced with regular HD springs/ shocks about 2 years ago, because the bags were beginning to leak. Not the "tail dragging" profile we see on these cars, but enough to warrant replacement.
Other car is a 2003 P71 with "Street Appearance Package"; very clean and smooth running. Cloth seats and carpet instead of vinyl and rubber. Ford sent me a build sheet on this P 71, but I've misplaced it; now, they charge $18 or so. Mine was free in 2009.
#7
11-19-2014, 12:43 PM
hanky, you seem knowledgeable on these Vics. I was a fleet mechanic and foreman for 20 years at 2 different places, but got out of it for something else around the mid 80s. I put the pressure gauge back on semi permanent, with nylon ties, where I can see the needle move from the driver's seat while the hood is up.
We've had 2 nights with temps in the upper teens now. Yesterday I periodically ran tests on the car. It wouldn't start first time yesterday, but did start after several tries; that's when I put the gauge back on. After sitting for about 3 hours, the pressure had dropped to 2#. I turned the key, and the pressure went to 32#(fast) and the car started and ran fine. During one test later, the gauge stayed at 20# with the key on. It started but stumbled a few seconds, then died. I turned the key off then back on. The gauge jumped to 32# and the car started and ran fine. Rest of the day was fine.
About noon today, I checked, and the pressure had held at 20# overnight. I turned the key, and it instantly dropped to 0#. I turned the key on/ off several times; still 0#. I attempted to start it and it stumbled a couple times, but no start. Then I rapidly turned the key on/ off in succession. Suddenly, the pressure sprang to 32#, and it started and ran fine. It's almost like a plug of ice was still in the line somewhere, and the rapid on/off broke it loose.
Another thing I've observed is that sometimes it will hold pressure after a shutdown period, and sometimes the pressure will drop as low as 2# awhile after shutdown.
I've heard there is a check valve some where between the pump and the lines; I guess that valve is in the tank or likely on the pump itself? Thanks for your help.
We've had 2 nights with temps in the upper teens now. Yesterday I periodically ran tests on the car. It wouldn't start first time yesterday, but did start after several tries; that's when I put the gauge back on. After sitting for about 3 hours, the pressure had dropped to 2#. I turned the key, and the pressure went to 32#(fast) and the car started and ran fine. During one test later, the gauge stayed at 20# with the key on. It started but stumbled a few seconds, then died. I turned the key off then back on. The gauge jumped to 32# and the car started and ran fine. Rest of the day was fine.
About noon today, I checked, and the pressure had held at 20# overnight. I turned the key, and it instantly dropped to 0#. I turned the key on/ off several times; still 0#. I attempted to start it and it stumbled a couple times, but no start. Then I rapidly turned the key on/ off in succession. Suddenly, the pressure sprang to 32#, and it started and ran fine. It's almost like a plug of ice was still in the line somewhere, and the rapid on/off broke it loose.
Another thing I've observed is that sometimes it will hold pressure after a shutdown period, and sometimes the pressure will drop as low as 2# awhile after shutdown.
I've heard there is a check valve some where between the pump and the lines; I guess that valve is in the tank or likely on the pump itself? Thanks for your help.
#8
11-19-2014, 01:40 PM
Thank you for your vote of confidence. As I'm sure you already know sometimes we get lucky and make a correct diagnosis . As far as the check valve in the pump module in the tank , Yes, there is a check valve in there. It could be hanging up or there could be a problem with the fuel pressure regulator. If the regulator decides to stick it could also allow all pressure to drop or go right back to the tank via the return line. Some later vehicle models have a returnless fuel system where it all happens within the tank module because that is where the regulator is located. If you get it squared away with just IPA , great. With 20 plus years experience I'm sure you know what to do. Hope I just reminded you of a few things you might have forgotten.
#9
11-19-2014, 07:00 PM
The regulator passes the pressure test, by jumping to 40# when the vacuum line is removed, but I guess it could still be bad. No gas in the vacuum line either, that would show a diaphragm leak.
I did my 3 PM test, and had to once again rapidly turn the key on/off several times to get any pressure. I warmed it up, and drove it 5 miles about 5 PM; ran and accelerated as always. Still can "scorch the road"; never a falter at all.
I went out about 7 PM, and the pressure had dropped to 2#. I turned the key, and it jumped to 32#, and started fine.
I have noted that after running it awhile, I turn it off and the pressure instantly drops to about 26-28#. I then turn the key back on, and pressure jumps to 38#...strange.
I park it on ramps under the rear wheels, in case I need access to the tank and lines. The plate for the pump is on the lower front edge of the tank. Hopefully, the pump can be accessed without dropping the tank! It appears to be a possibility, although the right tailpipe passes between the axle and the tank.
Do you know of any type additive can be used to clean the lines and pump? I also put in a second bottle of Heet this afternoon. Thanks
I did my 3 PM test, and had to once again rapidly turn the key on/off several times to get any pressure. I warmed it up, and drove it 5 miles about 5 PM; ran and accelerated as always. Still can "scorch the road"; never a falter at all.
I went out about 7 PM, and the pressure had dropped to 2#. I turned the key, and it jumped to 32#, and started fine.
I have noted that after running it awhile, I turn it off and the pressure instantly drops to about 26-28#. I then turn the key back on, and pressure jumps to 38#...strange.
I park it on ramps under the rear wheels, in case I need access to the tank and lines. The plate for the pump is on the lower front edge of the tank. Hopefully, the pump can be accessed without dropping the tank! It appears to be a possibility, although the right tailpipe passes between the axle and the tank.
Do you know of any type additive can be used to clean the lines and pump? I also put in a second bottle of Heet this afternoon. Thanks
#10
11-20-2014, 02:50 PM
Pressure held at 20# overnight (16 hours) last night, but dropped like a rock to 0 when I turned the key. Had to turn key on/off a couple times, then pressure jumped to 32#, and car started and ran fine.On shutdown, the gauge slowly rises from 32# on up to 38#, for some reason. After this afternoon's session, the gauge dropped back to 0 in about 2 hours, but jumped to 32# when I turned the key, then it started/ ran fine. I'm thinking the check valve is bad; but it's inside the tank. I thought about seeing if there is some way I can install an additional check valve some where in the external fuel line?