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Fuel Pressure Problems on long drives

  • Thread starter Thread starter 885.0conv
  • Start date Start date Aug 23, 2011
8

885.0conv

Member
Jan 9, 2008
238
0
16
Phoenix, Az
Aug 23, 2011
#1
  • Aug 23, 2011
  • #1
I recently moved further away from my work so I added about 20 miles each way. Since my fuel gauge isn't working I would fill up when the trip odometer would hit about 120. One day the fuel pressure dropped from the 40 to 20 and the car suddenly died when the odometer was reading 76. I had thought this was because of moving farther away my engine sits in the 3K range on the highway due to the 4:30's. But today after filling the tank full the same thing happened and the odometer was only reading 25. I recently replaced the fuel pressure regulator, charcoal canister, and fuel purge valve by the canister. I noticed the fuel pressure was not changing between idle, and WOT so I changed the above parts. After waiting twenty minutes the car fired up and fuel pressure was at 40 the rest of the way home. So I am thinking it has to due something with the heat. I just don't know what else to look at. Here in Phoenix we are hitting the 110's this week. Any suggestions or should I just wait til it cools down here. Thanks for the help.
 

jrichker

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#2
  • Aug 24, 2011
  • #2
It sounds like the fuel pump is in the early stages of dying. Here's some troubleshooting tips to try when it is acting up.

Fuel pump pressure test
Disconnect the larger of the two fuel lines up by the Schrader valve. It is the return line and does not have the Schrader valve on it. Find a piece of rubber fuel hose and clamp it on the return line coming from the regulator. Stick a bolt in the other end of the hose and make sure that all your connections are tight and leak proof as possible. When this powers up, you don't want fuel squirting everywhere. Hook up the fuel pressure test gauge. Turn the ignition switch on and watch for leaks. You may want to use a helper inside the car to cut the switch off quickly if you have a leak. To trick the fuel pump into running, find the ECC
test connector and jump the connector in the Upper RH corner to ground.
.
Caution!!! You have blocked the return line for the fuel pump! Pressure will rise very quickly past safe levels with a good pump
If the pressure goes up past 55 PSI, the pump is good and the fuel pressure regulator is bad. If the fuel pressure does not hit 55PSI or more in a few seconds, the pump is bad or you have electrical problems.
 
8

885.0conv

Member
Jan 9, 2008
238
0
16
Phoenix, Az
Aug 24, 2011
#3
  • Aug 24, 2011
  • #3
The fuel pump was replaced about 6 months ago but I will do the test and see. Thanks.
 
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