Mechanics

SUPREME ~ SOLUTION TO INTERMITTANT STARTING PROBLEM WHEN ENGINE IS WARM

1990 Oldsmobile Cutlass • 174,104 miles

3.1 V-6. Wires and plugs all in good working order. All coil packs replaced in last two years. Starter works great. Service engine light for EGR control comes on when driving occasionally and goes out by itself. Has for 5 or 6 years
Within last 4-6 weeks - after parking car for a short period ( like at the store ) try to start car and engine just turns over. It seems to take longer time to sit to get started now - up to half an hour wait time.
Took ignition module in to parts jobber ( Auto Zone ) for a test - they ran 12 passes - came up o.K.
When in cold weather, car will hesitate when first driving after initial warm up. Have always run injector cleaner at regular intervals. Throttle body was sprayed / cleaned last fall, but you can only get so deep.
Thanks, Steve.
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Cutlass FWD
July 5, 2012.



All "crank, no start" conditions are approached in the same way. Every engine requires certain functions to be able to run. Some of these functions rely on specific components to work and some components are part of more than one function so it is important to see the whole picture to be able to conclude anything about what may have failed. Also, these functions can ONLY be tested during the failure. Any other time and they will simply test good because the problem isn't present at the moment.
If you approach this in any other way, you are merely guessing and that only serves to replace unnecessary parts and wastes money.

Every engine requires spark, fuel and compression to run. That's what we have to look for.

These are the basics that need to be tested and will give us the info required to isolate a cause.

1) Test for spark at the plug end of the wire using a spark tester. If none found, check for power supply on the + terminal of the coil with the key on.

2) Test for injector pulse using a small bulb called a noid light. If none found, check for power supply at one side of the injector with the key on.

3) Use a fuel pressure gauge to test for correct fuel pressure, also noticing if the pressure holds when key is shut off.

4) If all of these things check good, then you would need to do a complete compression test.

Once you have determined which of these functions has dropped out,
you will know which system is having the problem.

Wrenchtech
Jul 5, 2012.