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When the engine does not start, does it crank over and not start or does it not even crank over?
We will have to pinpoint what the engine is missing.
All three of these are tested when the engine is being cranked over. There are two way of checking for fuel. Fuel pressure and fuel trigger. Both are very important and must be present for the car to start. Fuel pressure is self explanatory. You just hook up the gage and see what the reading is. Fuel trigger is check with a noid light. The injector gets unplugged and the noid light gets plugged in to the injector clip. With the engine cranking over, this light must blink. This is the signal to the injectors from the computer. You can have all the fuel pressure in the world, but it wont matter if the injector is not pulsing gas into the cylinder like it should! Compression tester, spark tester, fuel pressure gage and noid light are all accessible at your local auto store. All three tests play a very important part in diagnosing a no start condition. Be extremely careful when doing these tests.
A simpler test would be to see if it runs on starting fluid. If it does, then you know you have spark and compression and you simply have a fuel delivery problem
If fuel issue, are you saying change injectors or some control? The pressure was checked when we changed the pump.
So the fuel pressure is good?
Do we have spark?
How to check spark when this motor has inclosed and cant get to spark plugs? Just check with starting fuid is best?
You could pull off the cover and see if there is spark while cranking. You might need an assistant to crank the motor over while you watch for spark.
Does the engine run with starting fluid?
I will check all this tomorrow, It has sit for 4 hours and it starts now. So I need to drive agian so it will not start. See after it cools down it will start. So it has somthing to do with heat I think. Could this be a coil issue?
It is possible!
The most common cause for this problem is a crankshaft position sensor. Check to see if there is spark when it will not start. If no spark, suspect a bad crankshaft position sensor.
SO does it continue to run as of now?
Or does it just run with starting fluid?
It will continue to run and only takes a small hit of starter fuild to get started. After starting will run forever until you turn car off. Then it will not start until the car sits for 4 to 6 hours. After sitting 4 or 6 hours it will start without starting fuild
I had it checked today and it was same as when would not start, the shop said it was fine, but I forgot to ask the exact pressure
If you can find out the fuel pressure... that would be great...
Ask them to show it to you so that you see it with your own eyes. This is the type of thing that we need to be dead sure about before we make a diagnostic decision.
I will have to tomorrow. Can I buy a fuel pressue gage at Autozone and where does it screw into?
It should just screw into the fuel rail. Here is a pic.
I will buy my own gage tomorrow, What pressue should I be looking for?
If the pressue is good, As I said we changed the fuel pump 2 times, Would anything else limit the pressure to throtle body?
FUel pressure should be about 43 psi. If the fuel pressure is up to par, then we check fuel trigger.
If the fuel pressure is low, then we check power to the fuel pump and check for restrictions in the fuel pressure line.
Fuel trigger is injector?
Fuel trigger is the signal from the computer to the injectors. You would use a tool called a noid light. It simply plugs into the injector connector after the fuel injector is unplugged and should blink when the engine is cranked over. It looks like this.