I was on here about two months ago chasing a no start issue. Installed new high pressure fuel pump and filter. Fixed the problem for a while, then developed a hard start issue after setting a while. Replaced Fuel Pressure Regulator and now starts great. Immediately after installing the Fuel Pressure Regulator is began to occasionally buck or miss when accelerating. Gradually getting worse. Research indicated could be throttle position sensor, but there are no codes except the 111 indicating all is fine. Seems there is a fuel system issue I keep chasing, but not sure where to look next. Plan on checking things this weekend and see if I can locate the valve for fuel pressure gauge so as to get a reading. It almost makes me think after replacing the fuel pressure regulator the increased pressure may have freed up crud in the lines and messing with injectors. Any thoughts/suggestions would be greatly appreciated. Thank you in advance. 1990 E250, 351 with Auto trans and dual fuel tanks, 41,600 actual miles. Doesn't seem to matter which tank I am running from. The rear tanks were reworked about 10 years ago, coated, in tank pumps replaced. Doesn't appear to be an issue in that area.

 

If you need to run the pumps for testing with the engine off then ground #6 Do NOT run the pumps dry as it can burn them up!


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The fuel pressure test port is circled in red. Should have a black cap on it unless someone left it off.


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This will be a big help. Thank you

 

How long had the van sit with bad? gas in it
I had replacved 3 fuel pumps on a 2004 lately
What happened was it sat for 6 years with 1/2 tank of gas in it
I siphoned and pumped it out and got the new pump installed
Started having lean codes and drivability issues after a few hundred miles
Come to find out the fuel tank was so rusted inside with dried gasoline varnish, that when . after driving around with clean gas in the tank
All that black crap started coming thru and plugged the filter and pump intake filter (sock) 3 times
Remedy was a new fuel tank (fixed now) Thank God

 

Thank you for sharing. The last 10 years the van has had less than 5K miles put on it. During COVID it was not used although I tried to drive some just to keep it with fresh fuel. I'm not sure how long the last tank of gas sat there (maybe a year), but I did siphon it out. Since it looked and smelled normal I ran it in my garden equipment with no problems. The tanks were kept full so I am hoping I don't have to drop tanks. Headed to pickup a Fuel Pressure Gauge to see what the pressure is doing. If not within specs, I may put old regulator back on and see what's happening. Seems odd the new problem came exactly at the time the regulator was replaced. Obviously the old regulator was weak due to the hard start issues it was having. I will also check the vacuum line. Thanks again.

 

Be careful of the parts you get from auto parts stores. For some weird reason, this 5.8l engine is not happy if the right part is not installed.
I recalled having an issue where my van wouldn't start after replacing the FPR I had purchased from the store. So I was I had to put the old one back just to keep my van running
And the same issue happened with other parts such as the coil, and TFI module, just to name a few.

Hook up a fuel pressure gauge in order to rule out fuel pressure issues with your van.
You can loan the tool from most auto parts

good luck

 

Fuel pressure key on, not running 30psi, after starting steady at 34psi. Turn off engine and waited 10 minutes. Reads 25psi. I'm stumped. Seems in range based on what I read.

 

Correction, 28 psi 10 min after turning off.

 

OK, I originally said I had no codes (jumper method reading flashing engine light), I begin to question my counting. I was seeing what I thought was 3 sets of 111, but somewhere I read that the codes flash twice. Ok, so I can not count the lights. I tried Engine On self diagnostics and got some strange codes but maybe some helpful ones as well. Keep in mind reading blinking check engine lights are a pain. Going to get reader in the morning so the machine can do it for me. Thus far I am pretty sure I have the following codes 113, 122, 777, 465 (work backwards through the blinking lights in sets of 3). Will confirm tomorrow, but looking like a possible Throttle Position Sensor may be the culprit. While I know that is a bit of a pain, I would be happy if that ends up as the problem. Code reader tomorrow and then maybe I can be more exact. Thank you..

 

You need to drive it around with the pressure gauge taped to the windshield
Then see what it is as it is exhibiting the symptom
It takes a good gauge with a long hose for that
Here is a picture of my snap-on gauge taped to an 04 heritage windshield
Pressure would drop to 5 psi.as the truck was starving for fuel

 

 

[QUOTE=annaleigh;20532033]If you need to run the pumps for testing with the engine off then ground #6 Do NOT run the pumps dry as it can burn them up!


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The fuel pressure test port is circled in red. Should have a black cap on it unless someone left it off.


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OK, I now know a little more. Yesterday I reported that fuel pressure was within specs. Got hands on code reader and KOEO code 11, so nothing. Engine running test performed 3 times. 1st time Code 11. 2nd time Code 73. 3rd time Code 13. On this third test I noticed the fuel pressure dropped to about 10 lbs. so that probably explains the code 13. Can throttle position sensor cause a drop in fuel pressure? Seems odd from what I know. Keep in mind, all this started after replacing the fuel regulator due to hard starting issue. Tempted to put old fuel regulator back on and test again. Thoughts?

 

Update, changed New Fuel Regulator back to old one. Ran KOEO code 11. On to KOER test 1st and 2nd time Code 11. Beginning to think its fixed. 3rd time my wife sat in Drivers Seat while I waited for the response codes. Code 72 and 73 BUT I do not think she pressed the throttle enough. 4th try was the same. So, I ran a 5th. This time the fuel pressure dropped to less than 10 lbs, and idle dropped, Code 13. So, all in all I have ruled out the Regulator (going to put new back on since I can see the old one slowly leak pressure down), I do not believe the Throttle Position Sensor is bad now, I believe I have some sort of pump problem. Since the High Pressure Pump was just replaced and appears to be working fine, I figure I must have a problem in the tanks. Since there are two tanks, all this has been running off the rear tank, I am going to let it cool down and then do it all over again on the front tank. When test driving I did not detect a difference between tanks, but with gauges hooked up maybe I can find some difference. Really odd the way the pressure is fine then all at once the bottom drops out and goes to 10 lbs. It does come back to 35+/- in less than a minute or so. Just odd.

 

Run test again running on front fuel tank, could not get it to act up. Going to try and drive it a few days off front tank. If the problem goes away it could be a check valve or pump in rear tank and tank comes out. I'll keep you good folks updated. Thank you.

 

You will find that the crossover valve is causing your lack of fuel (you should feel lucky it runs on the front tank)
Those 3 pump systems have been doing just that for years now
Hence the crossover valves were obsolete by the late 1990s
The updated crossover valve for the 2 pump systems will not work