No start but have spark and fuel

Welp..I’ve tried everything I can think of with this car and it STILL won’t start..I’m totally out of ideas so I’m putting the hood on it tomorrow and pushing it back outside until a guy I know can look at it (he was a Mazda tech for 15+ years so hopefully he can find something we overlooked).

I hate to give up on it being so close but man..I seriously have looked at every possible thing, even tracing wires and grounds with no luck...Guess it’s just fate telling me to hurry up with swapping my 350 into my slammed Chevy 1500 lol hopefully working on something familiar will refresh my head and thinking process on the Mazda.
 
Ran across a YouTube video earlier about how the factory alarm system can keep them from starting. Looked around and didn’t see anything for it so I just kept looking around the car to quadruple check everything. Pulled the dipstick and it smelt like gas...is the head done for fellas?..
 

pcb

The Diagram Dude
:
2002 MP5
You have to remove the pistons to check them.

This is a piston from my parts car.
The oil drain holes are plugged right up.











 

pcb

The Diagram Dude
:
2002 MP5
No, it shouldn't but if your engine is getting fuel but it isn't igniting, then you could have liquid gas getting past the rings.

Were the tops of your pistons and the combustion chambers all carboned up?
 
No, it shouldn't but if your engine is getting fuel but it isn't igniting, then you could have liquid gas getting past the rings.

Were the tops of your pistons and the combustion chambers all carboned up?
No,it really wasn’t too bad. It had a little but I mean it’s got 185k on it. I’m pretty sure it was just a bunch of gas that got pushed into the oil passages because we cranked it over ALOT in a weeks time,I was just thinking warped head since it wants to start but won’t.

by the way...would painting the crank pulley affect how the crank sensor reads?? I painted my pulley to match my valve cover,idk if it would mess with it or not but that’s pretty much all I got for ideas lol unless there’s just a bad ground somewhere in the fender
 

pcb

The Diagram Dude
:
2002 MP5
... bythe way...would painting the crank pulley affect how the crank sensor reads?? I painted my pulley to match my valve cover,idk if it would mess with it or not but that’s pretty much all I got for ideas lol.

That's possible. Dirt on the toothed ring can cause the sensor to malfunction.
Maybe sanding the paint off the edge of the teeth might be a good idea?

Did you measure the gap?
That's important.


Did you do all the testing of the crank sensor?












 
That's possible. Dirt on the toothed ring can cause the sensor to malfunction.
Maybe sanding the paint off the edge of the teeth might be a good idea?

Did you measure the gap?
That's important.


Did you do all the testing of the crank sensor?












Yessir,checked all of that last time it was in the garage before I gave up on it. It’s gotta be the paint throwing off the sensor,I’ve never seen anyone else paint a crank pulley on a P5 before. If dirt will throw it off I’m sure my 3 coats of white paint will too lol..hopefully after I sand the teeth and get the alternator off the parts car,I can have it running. Still need to check my fuel pressure though because I don’t hear my pump kick on but I still got gas where it should be.
 

pcb

The Diagram Dude
:
2002 MP5
Actually, you said that you have spark and fuel.
If there is a problem with the crank sensor, the ECU kills the spark.
 

pcb

The Diagram Dude
:
2002 MP5
If it was me, I might consider some of that engine start spray, that you spray in the intake.

That's just a guess though, you can wreck an engine with too much of that stuff.
 
If it was me, I might consider some of that engine start spray, that you spray in the intake.

That's just a guess though, you can wreck an engine with too much of that stuff.
I’ve tried it and it still won’t fire on it. It will sputter a few times like it wants to fire but then just goes back to cranking
 

pcb

The Diagram Dude
:
2002 MP5
So it’s most likely fuel pressure or compression then?

That makes sense to me.

Here's a thread about replacing the fuel filter and fuel pump.

 
That makes sense to me.

Here's a thread about replacing the fuel filter and fuel pump.

Awesome, thanks man! I appreciate the knowledge.
 

pcb

The Diagram Dude
:
2002 MP5
... Still need to check my fuel pressure though because I don’t hear my pump kick on but I still got gas where it should be.


I just went out to my car, put the key in the ignition, and turned it to run.

I didn't hear the fuel pump at all.
I don't know if I just couldn't hear it or if the ECU hadn't turned it on?

I'm pretty sure that the system can store pressure for a while (I think that's what the pulsation damper does?) and the fuel pump only kicks in when the pressure starts to drop.

So if you don't hear the fuel pump, that may be normal.



There is a way to turn on the fuel pump with a jumper wire.

You're supposed to use it to turn on the pump to check the pressure.


I'm completely guessing here, but maybe you could connect a jumper wire to bring it to maximum pressure then try to start it?


I don't know how the car monitors pressure to turn the pump on and off or if maybe the pressure would be too high to start the car, but I think I would try it if it were me.

I know that there is a PRC solenoid valve that is supposed to kick in the fuel pump to increase the fuel pressure for a hot start.
Perhaps there is a problem with that solenoid or system that is messing with your fuel pressure, assuming that you do have a fuel pressure issue?


Remember I'm just guessing so you'll have to use your own judgment.

(I can't upload pictures at the moment, but the info about the jumper wire is in the FSM on page 01-14-4.)



I'm thinking that your no-start situation may be because the ECU isn't turning the fuel pump when it's supposed to?

Or perhaps your fuel filter is clogged, along with a worn-out fuel pump, and your car can't get up to proper pressure?
 
I just went out to my car, put the key in the ignition, and turned it to run.

I didn't hear the fuel pump at all.
I don't know if I just couldn't hear it or if the ECU hadn't turned it on?

I'm pretty sure that the system can store pressure for a while (I think that's what the pulsation damper does?) and the fuel pump only kicks in when the pressure starts to drop.

So if you don't hear the fuel pump, that may be normal.



There is a way to turn on the fuel pump with a jumper wire.

You're supposed to use it to turn on the pump to check the pressure.


I'm completely guessing here, but maybe you could connect a jumper wire to bring it to maximum pressure then try to start it?


I don't know how the car monitors pressure to turn the pump on and off or if maybe the pressure would be too high to start the car, but I think I would try it if it were me.

I know that there is a PRC solenoid valve that is supposed to kick in the fuel pump to increase the fuel pressure for a hot start.
Perhaps there is a problem with that solenoid or system that is messing with your fuel pressure, assuming that you do have a fuel pressure issue?


Remember I'm just guessing so you'll have to use your own judgment.

(I can't upload pictures at the moment, but the info about the jumper wire is in the FSM on page 01-14-4.)



I'm thinking that your no-start situation may be because the ECU isn't turning the fuel pump when it's supposed to?

Or perhaps your fuel filter is clogged, along with a worn-out fuel pump, and your car can't get up to proper pressure?
I think it’s fuel pressure still. Not 100%,I was supposed to pick up a parts car Saturday morning but that fell through. Gotta wait until I get another alternator before I start messing with it again unfortunately. An alternator from an MPV would work,right?..
 

pcb

The Diagram Dude
:
2002 MP5
I don't know about an alternator from an MPV.
Our alternator is controlled by the ECU and it may be specific to our car.

I remember some people installed an alternator from a different vehicle that had a built-in regulator.
They had to do something to get the battery light to turn off on their dash.

You could probably compare part numbers between the two vehicles to find out if it's the same alternator.
 

pcb

The Diagram Dude
:
2002 MP5
I checked out the descriptions of the alternators at Rockauto and the alternators appear to be different.
They are both externally controlled but there are a lot of differences.

They may even have different dimensions with different bolt holes?






 
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