2002 chevy venture , hard to start, have to cycle key 2 or 3 times, fuel pressure replaced, maf replaced, map replaced, cam and crank sensor replaced, ignition coil replaced fuel filter replaced ,pcv replaced, no problem w pk3, no vacuum leak (smoke test performed) good battery and overall voltage, but fuel pressure only shows 20 psi (switch on ,and running) and as soon i shut down the engine drops to 0 immediately, no gas smell, no shorted ground only one code P0171 b1 lean condition O2 sensors ok...any suggestion?? .

 

Hi !
Initially check the vacuum leak.
The best way to check for vacuum leaks - to run the engine and use carburetor cleaner spray to spray around the perimeter of the intake manifold. If you come across a vacuum leak, the idle will change.
Possibly also be caused by lack of fuel to the engine. Try replacing the fuel filter. Check fuel pressure. Check the nozzle and the wires towards them. Fuel pressure should be 52-59 psi with the key on, engine off. If the fuel pressure is lower than specified, the fuel pump should be replaced.
If all these things check okay, the problem could be a faulty O2 sensor.

 

you have a fuel delivery problem and you have a fuel leakdown problem. 02 sensors are ignored on start up until the engine is in closed loop operation. You have an obvious fuel issue, fix it first.


you replaced the fuel pressure....means what?


first, isolate the leakdown problem. put a fuel pressure gauge on the system. clamp off the return line, cycle the key to prime the system. observe if the pressure drops. if not, its probably the fpr. If yes, prime the system again and clamp off the fuel feed line....does pressure drop?


the fuel system can only leakdown from the check valve in the fuel pump, fpr, injectors or leak externally.


the lack of fuel supply pressure can be from a bad fuel pump or pump leaking internally in the tank, clogged fuel filter or power and grd problems to the fuel pump itself.


a fuel pump leaking internally can cause both problems.

 

Follow tech2 advise, resists the temptation to change parts without understanding the reasons why.

 

how you clamp a metal hose followed by a hard plastic tubing from fpr to tank???

 

how you clamp a metal hose followed by a hard plastic tubing from fpr to tank???

 

i replace all those sensor not because the fuel pressure problem, just because is a 14 years Venture and is about time to do so and its was fun anyways...but Thanks for your advice

 

check where the steel line comes off the frame rail to the engine for a rubber section.


if there isn't one, professionals splice in a premade line with shut off valves. they can be made up for $25