1986 Buick LeSabre with 3.8L V6 died while driving. Engine cranks but will not start. Checked fuel pump, injectors, lines, plugs and wires. Spark appeared possibly weak on the LeSabre compared to the same plug tested on a 1999 Saturn. It has been suggested that there may be a timing issue. Any thoughts?

next time it dies, cranks and wont start, do this if you have someone else with you. carry a spare spark plug, then when the problem arises pull off a plug wire put the spare plug into it and ground the end somewhere in the engine bay, then have someone bump the key and watch to see if the plug has a spark or not, that will at least tell you what problem to go searching for. if it had air, it still does when it dies so it will either be spark or fuel related. just because the pump runs, doesnt mean the ecu is telling the injectors to fire, so still could be a fuel issue. is the check engine light on?

Have you checked cam timing?If it has jumped a tooth or two it will not start.

You will need a fuel injector testor, about a $100, and a fuel pressure guage, about a $100, to flow test the injectors.

You can ohm check them with an ohm meter to see if one or more has shorted windings. Remove the electrical connector and test between the two pins. They should all be about the same ohms. If one is significantly lower than it is probably bad. Its best to check them when they are hot (after the engine has warmed up).

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As you have probably figured out by now, you will have to treat it as a no start and troubleshoot it when it fails to start. Until you figure out if you are loosing spark or fuel to the injectors when the engine dies you have no direction to go in.

'86 does not need cam sensor to run. Besides cam sensor there is a pickup magnet on cam gear. Front cover must be removed to change. As long as asd relay is activating and wiring / fuses have been verified as good. Then I would suspect your crank sensor as faulty. A scan tool would be useful for this, as you could check cranking rpm's to verify.

u need a fuel filter posibly a fuel pump. start small then go big. could also be your egr valve.

crank position sensor, camshaft position sensor or an injector with too many ohms resistance. when you turn the key to the on position you should hear the fuel pump come on for a few seconds. if not suspect fuel pump relay or fuel pump

you will need to determine if it's a no spark issue or a no fuel issue.

When the car wont start spray some carb cleaner or starter fluid into the intake and try to start. if it does start and run for a few second then the problem is with the ignition side

check for spark by removing a spark plug lead from a spark plug and putting a good spark plug in the wire, use a jumper cable and clamp one end to the spark pug thread and the other to battery ground. Turn the engine over and you should see spark.

is the check engine light on? if so get the computer scanned, autozone will do it for free

Check for gas or spoark. The fuel pressure should be high. The gas should enter the cylinder.

Test by putting some starting fluid into the throttle body. If it starts, you have spark but no gas.

Test by putting spark plug tester on one of the spark plug wires to see if it sparks to ground.

If it does, then you have spark.
If not, then the coilpack or coil ignition system could be bad.

If the fuel injector isn't pulsing, it could be a computer.

This is either no spark or no fuel. Remove a spark plug and hold it with a pair of pliers with rubber grips. ground the tip of the plug on the block and then have someone crank the engine while you look to see if there is a spark in the tip. If you have a spark in all of the plugs then it is no fuel. If you do not have spark; then it could be wires, or any of the ignition parts. You can loosen a fuel line a LITTLE while holding a rag under it to catch the fuel. Have someone crank the engine to see if fuel comes out of the line. Work your way from the injectors back to the tank. You could have a bad fuel pump or dirty fuel filter.

even if you have preasure in the line that does not mean you have fuel going into the engine. you should check the injectors to see if they are spraying and if not you need to check the injector pulse to find out if the PCM is sending the signal to them to spray. to check injector pulse you will need a noide light to test the pulse it the light lights up you have pulse, but easy way to check is pull an injector and turn the engine over see if it sprays.