bravada wont start when warm

[oak2001raid]

I will try to make this short..
I have a 1999 olds bravada, been kind of running rough.. missing alittle when driving. Now a bigger problem. I can start it, and it runs great, problem is.. when I shut if off it wont start. turns over fine, and has a brand new battery.
Sounds like it's not getting gas(even tho I can hear the fuel pump running). After it sets about a half hour it starts right back and runs great untill I shut it off again.

[old_master]

The first, and easiest thing to check is spark. Do you have good blue, (not orange) spark at each spark plug when it will not start?

[oak2001raid]

yeah getting spark

[old_master]

Check fuel pressure and leakdown. Ignition ON, engine OFF, fuel pump running: Must be 60psi to 66psi and must remain above 55psi for 3 to 5 minutes after the fuel pump shuts off.

[oak2001raid]

thanks for the help... I did check fuel pressure.. it was holding about 60 psi.

This problem is a couple weeks old, i tried about everything I know of and more. Any help is VERY apprciated

[old_master]

Is there a security system installed on the vehicle, factory or aftermarket? Security systems typically disable the fuel injectors. The vehicle has passlockII from the factory and it's possible it's disabling the injectors. If it's a passlock problem, the security light should be ON.

[oak2001raid]

No lights like that only check engine light is on.... but i probably should have mentioned this earlier... Service engine light comes and goes. only trouble code is PO300.
I understand this is random misfire on multiple cylinders. But the problem with that code is it could be literally a dozen things.

[old_master]

All P0300 series DTC's are almost always caused by secondary ignition faults. They include spark plugs, spark plug wires, distributor cap, distributor rotor and the ignition coil. The 4.3L engine is very fussy when it comes to ignition parts. Aftermarket parts do not perform well, especially when it comes to the distributor cap, rotor and spark plugs. Best to stay with AC Delco on those parts.

There is a TSB concerning the vents in the distributor housing being clogged, which will set a P0300 DTC in memory and turn the SES light on. Condensation forms on the underside of the cap and it can not be ventillated if the vents are clogged. The TSB instructs you to remove the vent screens completely and to replace the distributor cap and rotor. Use a dab of silicone dielectric grease on each terminal, (inside and out) of the cap.

[oak2001raid]

would any of those cause the "no start when warm" condition?

[old_master]

Absolutely! If/when condensation accumulates in the cap, when you try to start it after a short hot soak, the spark jumps all over inside the cap, causing a no start and in some cases, setting the P0300. The warm, moist air inside the engine rises up past the distributor bushings and condenses on the under side of the cap. After it dries out, it starts right up.

[oak2001raid]

Update.....

Checked the distributer cap this morning, it seems to be OK. I really dont think its gonna be a firing problem, because it does fire when in "no start" condition.

I beleive its going to be in the fuel system. When it wont start, its not getting any fuel. I can put a little in the "carb" and it will start. Shuts right back off after that fuel is gone. The fuel pump is still working, Im just not getting it to the carb.

[oak2001raid]

another note ...The security light does come on after i turn the motor off, it flashes for a couple of minutes then goes off. but it has always done this. I dont know if this has anything to do with my problem(im looking at passlock posts now)..
I am getting good fuel pressure up to at least the fuel rails, but not to the injector

[oak2001raid]

Another update:

Disabled passlock(got the info from other posts, thanks all)
No change, ran it about 20min, ran perfectly. shut it off wouldn't start back.
Wait 10-15 min starts back run good again.

*security lights flashes after I shut off the motor.
*getting good spark
*getting fuel to fuel rail, not to "intake"

[old_master]

Make sure the pink wires to the injector pack have battery voltage when the ignition is in the RUN and START positions. The ECM supplies a ground signal sequentially to each injector to energize it.

[oak2001raid]

not to sound dumb, but where is the injector pack?