i've been having the same problem with my 90 lesabre. as the other poster. today i tried the idea about spraying some starting fluid to see if i'm getting fuel, did not start. then i checked for spark at the spark plug and was surprised to see that i did have spark. this leads me back to the fuel system. could it be the fuel pressure regulator? or injectors? like the other post, when it starts it runs great. any help would be appriciated

 

Thanks for posting ...


What have you done so far?


The regulator trys to maintain the 45psi. Then it overflows the remainder back into the tank. Some have checked this overflow and found it very short on volume.


If the pump is bad it will normally fail during heavy power but have had issues of just not running cold.


Injectors fail first by leaking and then getting stuck, dirty.They dont wear out like they used to.


Coil packs fail under load, cold, hot. They get cracks and moisture.


They also sometimes will fire with the plug pulled and not under pressure in the cylinder.


A somewhat intermittent problem is tuff.





Good Luck

 

bassasin, thanks for the help first off. over the past 6 months i've changed quite a few parts. the car is a low mileage car that sat garaged for some time so i started by cleaning the gas tank, and a new fuel pump, and a new fuel filter. the car ran then but still wouldn't start sometimes. a freind told me to try the fuel pressure regulator. i didn't that and thought it cured the problem.

this was all in warm weather. since then it's gotten colder the problem has come back, and worse. when i checked for spark today i checked between the wire and plug, without removing the plug, so i'm assuming the cylinder would still be under pressure. and i did have spark.

 

The obvious is if its getting timed spark and fuel mix with compression, it should go vrooom. .
Spark must go through to the gap.

Divide and conquer.
When it doesn't start, check for wet plugs and smell for gas.
Flooding is the only thing left, if your correct.

</span></font>No firiring? . No pops?.. Nothing?
Does it have to sit and then it starts?

Hmmmm.. seems like Im repeating my forum posts.

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Edited by: bassasasin

 

i have posted this question before. but as i said i thought i was getting somewhere. i will pull a plug tomorrow and check to see if it's wet. if i crank it over for a few seconds then when i release the key it will give a sputter, but it won't fire up. any ideas on what it could be if it is flooding? i'm going to try another fuel pressure regulator tomorrow, it seemed to work before. i just didn't know if it was a part that would go bad this quickly.

 

Could be flooding .. Here are some possibilities.
If theres a leaky dirty, injector it could flood. If the ignition module takes a bit of time before it fires properly, it could flood..
It also may be its not getting its start prime pulse. Usually theres a prime sent for start before it goes to ECM controlled pulses.

Flooding as I understand it is when the fuel mix is too high and the plugs are wet and the spark either travels across and doesn't fire hot enough to ignite.. .

The sputter you mention is an important clue.. Mechanics learn to hear those sputters and determine rich or lean, and such.

If you floor the throttle when it has a no start condition most cars will turn off the fuel injection during the start cycle.. The advantage is if the engine is flooding it can lean out and start. The disadvantage is trying a start with the throttle floored may not be reliable.

If its the regulator it would give problems when the engine does run.

But in difficult times its worth a try.

Good Luck..



Edited by: bassasasin

 

bassasasin, if it were a leaking or dirty injector would one defective injector cause flooding? also now that i think of it the sound is more like a poof or small backfire than a sputter. also, i do smell fuel after cranking for a bit.

 

Thats a good observation..One injector wouldnt cause what you discribe.
You may have heard where these cars have ignition on both the compression and exhaust stroke. Although Im not a believer in this function it is possible that the exhaust stroke has fired but that would not blow it out the intake. If your discribing exhaust firing, then unburnt gas gets into the exhaust and gets fired from hot gas from a another fired cylinder.

What you discribed reminds me of a previous posters where his coil pack was the solution. That is if your getting no firing during crank. I have heard of throttle position messing with the run after firiing well during crank.


Good Luck
Edited by: bassasasin

 

someone today told me to check my fuel pressure. i'm going to look for a gauge and see what i come up with.

 

Thats good but you did spray into the intake and it should fire a bit.