Hi Everyone,

It has been a bit of a struggle to start this car when cold. The temperature sensor is fine and the crankshaft position sensor has been changed. The spark plugs do not have much mileage on them and the wires are new. The cap and rotor are fine also. I keep the battery connected to a slow charger overnight.

Mileage is 130,000. This began a few months ago.

Once the car starts it runs fine with no problems. Does anyone have any advice?

Thanks so much,

Darren.

 

When mine did that very same thing it was the rotor slowly breaking down, eventually, maybe 4 or 5 months later led to car not starting at all.
Rotors a cheap on rockauto, may as well get a spare and give it a try?

Larry

 

Hi Darren,

I like Larry's suggestion about checking the rotor. Some of the aftermarket rotors and distributor caps are of suspect quality and tolerance. Also check for condensation in the cap, and check the distributor shaft for side-to-side play or signs of arcing to ground down the shaft.

When you say the temperature sensor is fine, how have you tested it? There are two temperature sensors. One is the single-wire sender that feeds the temperature gauge in the Instrument Cluster, and the other is the two-wire sensor that provides the signal for the Engine Control Module. Both are mounted on top of the thermostat housing. If the engine Coolant Temperature Sensor fails at a resistance that tells the ECM the engine is hot, the ECM will not apply cold-start fuel enrichment, leading to hard cold starting.

Hard starting can also be a symptom of failure of the Fuel Pressure Regulator, fuel check valve, or both. One simple test is to remove the vacuum hose from the FPR, crank the engine, then inspect the hose fitting on the FPR for signs of wet fuel. If present, the diaphragm has failed. When the FPR or check valve fails, the fuel pump must fully re-pressurize the fuel rail before the engine will start, which can lead to extended cranking, especially if your fuel injector filters or nozzles are obstructed.

Have you disassembled your air intake and crankcase breather system and cleaned out all of the gunk, and cleaned your Throttle Body and Throttle Position Sensor and the EGR and purge valve ports on the underside of the intake manifold behind the TB?

If the battery voltage while cranking falls much below 11 volts, the ECM may not trigger the ignition to fire, so it's worth checking your voltage while cranking. Even with a healthy, fully-charged battery, corrosion on the many battery power and ground connections can cause excessive voltage sag while cranking.

Inspect the wiring at your ignition coil and amplifier for overheating or deterioration.

Check the electrical connector at the Crankshaft Position Sensor for oil contamination and to be sure none of the connector pins have backed out of the connector housings.

Has your fuel filter been replaced?

Did you use the correct Champion RC9YC spark plugs or something else? These engines seem to run best on the cheap OE Champions.

It would also be worth cleaning the ground points in the engine bay, especially the ones referenced by the ECM: two on the intake manifold and one on the firewall behind the cylinder head.

Please keep us informed!

Cheers,

Don

 

Hi Don,

I cleaned out all of the muck from the intake system today. I will wait until tomorrow to see if the problem resurfaces. I so dislike that PCV system; it really does allow all kinds of garbage to condense a little too near to the throttle body. I also cleaned the deposits from the throttle body and sprayed the idle control motor with cleaner. I took steel wool and cleaned off the brass sweeper on the rotor but the car exhibited the same symptoms. This was prior to cleaning the mess from the intake system.

The fuel filter is relatively new, and the plugs are Bosch platinum which worked fine all last year. Thanks for all of the tips. I'll start it in the morning after a full cool down and see what happens. I do indeed get the one second fuel injection pulse when the key is first turned on.

Regards,

Darren.