99 4runner turns over but not start

[TonyMorris92]

We replaced the head gaskets, spark plugs, and one fuel injector. Sparks good and fuels good. And we checked the timing and that's good. We have pretty much taken the engine apart and put it back together a few times and can't find the problem. Any suggestions? Thanks for your time.

 

[Franky_Dabbs]

Did you check the simple things like the starter, alternator, battery, grounds??

 

[TonyMorris92]

Battery is fully charged. The engine turns over so the starters working. And the only ground line that I know on is the one that runs from the firewall to the passenger side cylinder head. Am I missing more? I haven't looked at the alternator.

 

[Doc2012]

firing order will make it not start.....

 

[TonyMorris92]

We checked the firing order it's all good... we really have no idea. Thanks for the idea

 

[MattJakobs]

May or may not help, really just a wild guess:
Check your fuel filter. Every once in a while my engine will turn over no problem but has a problem actually starting (I also have a number of things wrong with it including two dead cylinders but have a JDM coming soon) but someone recommended to me that the problem turning over could be that gas is just having a hard time getting to the engine.

 

[TonyMorris92]

Awesome thank you.. we will check it out. Right now we are open to anything. Thanks for the help

 

[TheDurk]

1. Consider that the ECU activates the fuel pump under two conditions:

a) STA signal from the starter because starter is energized (obviously needed to start engine

b) Continuous signal from the crankshaft position sensor (indicating motor is running. If this signal is absent, fuel is cut as soon as starter is de-energized.) I'd say CPS is worth a look, as they don't always set codes when they should. For example, if the single magnetized tooth is broken off the crank sprocket, the ECU won't know and the sensor will scan good. Likewise if the crank sprocket is mis-installed and not aligned with TDC.

2. There is a very important ground connection near the diagnostic plug on the driver's side of the engine.

3. You said timing is good. Valve timing or ignition timing? Whichever one you checked, check the other one.

4. Finally, I would also triple check the plug wire routing. This diagram has surprised many who thought they had it right...

 

[TonyMorris92]

Thank you thats very helpful i will check it out and keep you updated.

 

[TonyMorris92]

Thanks for all the help... i was at work when he fixed it so i dont know what was wrong but thank you for all your advice