1992 Chevy Blazer On going problems Can't seem to solve

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.

[quote:50414f042e="Wrenchtech"]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.[/quote:50414f042e]

Thank you for the response.
What we have found is a dry condition in the cylinders. I can detemine this as I have pulled the #1 plug several times and it is completely dry even after several attempts to start it. I have no way of testing the injector pulse but we have voltage at the injector itself. Personally I have come to the conclusion it is the injector unit that has failed but I dont know of any testing I can do without taking to a shop. thanks again

That would be pretty foolish to come that conclusion.
Someone needs to do some testing, whether it be you or someone you pay to do it.

[quote:540ee87714="Wrenchtech"]That would be pretty foolish to come that conclusion.
Someone needs to do some testing, whether it be you or someone you pay to do it.[/quote:540ee87714]

What testing can be done to make sure the fuel injection unit is working? Can you list alternative issues that may be causing no fuel to be in the cylinders? The fuel pressure is good since the fuel pump was replaced (it has been tested with a fuel pressure gauge). Spark has also been tested and is fine. Power is going to the fuel injector unit, but it is unknown if the unit is functioning properly because we do not know of any test without taking it to a shop. Compression has also been tested and is good.

Thanks once agian for your response

What is the fuel pressure?

As yet no one has confirmed that injector pulse signal is being delivered to the injectors. This needs to be tested before even considering that the injector could be faulty.