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**rogoman** · Mar 7th, 2008, 07:40 PM

OK, so the ignition timing is correct and there is good spark? At this point here are the other items to check:

- Major vacuum leak. Check the intake manifold nuts to make sure they are tight. Also check the intake plenum bellows at the throttle valve and at the MAF for cracks or loose clamps.

- You may have leaking fuel injectors. To test them, unbolt the fuel rail from the intake manifold and pull off the entire assembly. Keep the fuel hoses still connected and don't remove any individual injectors. Also keep the electrical connectors on the injectors. With the assembly now away from the intake, turn the ignition key to the run position WITHOUT STARTING THE ENGINE. Now observe each injector to look for leaks. There should be no drips.

Make sure you have at least 4 spare insulator rings for the injectors in case some are damaged during rail removal.

- The crankshaft position sensor that's inside the distributor may be bad. First check the harness connector for it.

- The IACV air regulator valve may be bad.

- The cam timing may be incorrect. Here's how to check it:

First disconnect the ignition coil wire, remove all the spark plugs and remove the valve cover. Have someone tap the starter while you have your thumb over the #1 spark plug hole. Once you feel compression, insure that the block timing pointer at the front pulley is pointing to the zero mark on the pulley: if not, manually turn the motor by hand clockwise or counter-clockwise until it's pointing to ZERO.

Remove distributor cap and insure that the rotor is pointing to #1 firing position. The #1 piston is now sitting at TDC COMPRESSION STROKE. The keyway for the cam sprocket should be at the 12 o'clock position. The top end of the timing chain mating (silver) mark should be at the sprocket gear mark; 3 o'clock position.

Mar 7th, 2008, 07:40 PM	#12 (permalink)
rogoman Keeping the peace Join Date: Dec 2004 Location: NJ (Philadelphia area) Posts: 1,963	OK, so the ignition timing is correct and there is good spark? At this point here are the other items to check: - Major vacuum leak. Check the intake manifold nuts to make sure they are tight. Also check the intake plenum bellows at the throttle valve and at the MAF for cracks or loose clamps. - You may have leaking fuel injectors. To test them, unbolt the fuel rail from the intake manifold and pull off the entire assembly. Keep the fuel hoses still connected and don't remove any individual injectors. Also keep the electrical connectors on the injectors. With the assembly now away from the intake, turn the ignition key to the run position WITHOUT STARTING THE ENGINE. Now observe each injector to look for leaks. There should be no drips. Make sure you have at least 4 spare insulator rings for the injectors in case some are damaged during rail removal. - The crankshaft position sensor that's inside the distributor may be bad. First check the harness connector for it. - The IACV air regulator valve may be bad. - The cam timing may be incorrect. Here's how to check it: First disconnect the ignition coil wire, remove all the spark plugs and remove the valve cover. Have someone tap the starter while you have your thumb over the #1 spark plug hole. Once you feel compression, insure that the block timing pointer at the front pulley is pointing to the zero mark on the pulley: if not, manually turn the motor by hand clockwise or counter-clockwise until it's pointing to ZERO. Remove distributor cap and insure that the rotor is pointing to #1 firing position. The #1 piston is now sitting at TDC COMPRESSION STROKE. The keyway for the cam sprocket should be at the 12 o'clock position. The top end of the timing chain mating (silver) mark should be at the sprocket gear mark; 3 o'clock position.