Knocking noise from rocker arm cover when it is off idle. *The car has not run since last April.*

I found out today that cyl. 2 and cyl. 4 where miss firing. Pulled plugs and were carbon fouled. The injectors were pluged. Ordered new injectors and will replace pluged cat. Will let you know if it is fixed.

The reason all the work was done is the po 300. I have checked the plug wiring and coils. The spark is good, used a spark tester for dis ign. Checked for vacuum leaks with carb cleaner. Have reset the check engine light and it returns.

I forgot to say the mass air flow sensor was replaced and map sensor. With the mass air flow sensor unpluged it runs worse.

Still have po 300. Have replaced cranck sensor, cam sensor, timming chain and gears, cam interupter magnet, upper intake manifold, lower intake gaskets, igniton module, fuel pump and fuel psi regulator, plugs and wires, fuel filter. Anyone have any ideas?

The crank sensor on the 3.8l's are a problem. They cause a no crank and no tach. Spray carb spray on the sensor and it should start for future referance.

I replaced the lower intake gasket. Also replaced upper intake. Replaced fuel pump and regulator. Now it won't run unless the gas pedal is floored. Any new ideas?

Thanks for all the info. found it at Pepboys. Autozone list the part but was on back order. Also GM could get it in 3 days at best.

The brake booster is hoooked up. I am going to inspect the lower intake gaskets for vacuum leak and or coolant in the intake. Note this car has had no trouble since 50,000 miles, until now. Just replaced the factory water pump, since it was off for timming chain and gear replacement.

Also replaced fuel filter, was clean.

Disconnected cat. no change. Pulled plugs, they looked good, not fouled or super white.

No I haven't checked the fuel psi yet. Yes po300 is the only code I get. The engine is fine up to 2000 rpm the craps out till 2500 rpms then at 3000 rpms is maxs. I used AC Delco plugs.

Yes have a new coil and swapped in all poistions no change.

I have a 2000 Pontiac Bonneville SLE with 180,000 + miles. With re occuring po300. replaced timming chain and gears. upper intake gasket, throttle body gasket, cam and crank sensor, ignition module, plugs and spark plug wires. Any thoughts?

I found the GM part number for interrupter 10456071.

I am replaceing the timmming chain and gears but the new cam sprocket did not come with the interruputer and lock ring for 2000 Bonneville SLE with engine vin k.

Just want to say hi.