luico

hi everyone i got an astro with a bad fuel pump but i replaced already and i check the pressure in the fitting on the top of the injector and the pressure its good but the engine dont start if a put a little amount of gas in the middle of the carb the engine then starts but rapidly gone off what are the possibilities part that are bad? i appreciate the help anticipate thanks.

luico

hey people it could be a crank sensor or not ?

old_master

Key on, engine off, pump running, pressure must be 60psi to 66psi. After 2 to 3 seconds, the pump will shut off and the pressure must remain above 55psi for 3 to 5 minutes. Post your results.

luico

old master thats right thats happend to me exactly in your comment but the engine dont start i verified the current on the top of the fuel injection and are good i called some tech in my area and they said it possible that the crank sensor could be dead it's that true or not ?

old_master

It is possible for the crankshaft position sensor to cause the engine to stall. The computer will keep the fuel pump relay activated as long as the computer receives a signal from the CP sensor. However, if the CP sensor is bad, the engine will not start at all. Near the underhood fuse panel there is a grey wire that goes to the fuel pump. Check it for battery voltage when the ignition is turned to the RUN position. It should show battery voltage for 2 to 3 seconds, then drop to near zero. When the ignition is in the START position, the wire should show battery voltage all the time. Post your results.

luico

hey master ill tested and the results are in run position stills up and when i'm turn the key to start position the battery volt gauge drop off a litlle.

old_master

Connect the fuel pressure tester and turn the ignition to the START position. See if fuel pressure stays above 60psi when cranking.

Then turn the ignition to the OFF position, the pressure should go up slightly, then drop below 60psi but remain above 55psi.

Old Bow Tie Guy

Hey Old Master,

Just joined the forum. I really enjoy the respectful and helpful tone here. Much different from other auto forums. I also have fuel delivery issues with my 2000 Astro. I tested the grey relay wire and showed 11.95v at run for 2.5 sec and only 9.5 at the start position. Shouldn't it have shown 12v in the start position?? What can I check next? The tank is out and sitting in the driveway (just call me hacksaw : / had to hacksaw the filler neck hose and vent tube and cut the plastic fuel lines due to severe corrosion) in case I need to go after the pump assembly. Thanks for your help. You can "E" me privately if that would be easier. Thanks.

Blue Bowtie

Welcome Aboard!

It's always a good idea to search the forum archives for similar problems and their results. However, when posting questions about your own specific situation, it would be better to start a new thread so it gets all the attention it deserves. Some members will look at the original post and confuse that situation with your's, and the original poster may see a new post in the original thread and think there is new information regarding the original topic.

Start a new thread and we'll take a close look at the specific of your symptoms.

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