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2002 Protege5 JDM Engine Swap help needed

I just finished installing my new engine I got from an importer and we put everything in...The car starts but dies immediately and I don’t know what to do now, there’s no check engine light or anything.
 

pcb

The Diagram Dude
:
2002 MP5
Check your cam and crank position sensors.

The ECU allows a few revolutions of the engine and if it doesn't get a crank signal it kills the engine.
 

pcb

The Diagram Dude
:
2002 MP5
Inspect it first.
It may not be the problem.

IIRC, the engine will run with no Cam signal, but it won't run without a Crank signal.

There is a code for the Crank sensor but the engine is killed so fast that it doesn't have time to register the code.












Check the toothed ring on the crank pulley.
Make sure it isn't bent, broken, or loose and wobbly.
Make sure it's spinning square and in alignment with the sensor.


Check the wire and connector and make sure it's plugged in and not frayed and shorting out the signal.
Follow the wire into the harness as best as you can.
 
One very common "failure to start" in these motors if any work is done in them is that the timing plate is installed backwards, IIRC the concave side should be to the outside and the spacing between the crank sensor and the "nub" on the wheel is about the thickness of a credit card.

Another big variable in this is that you don't know if the engine even ran when you bought it. If the timing belt breaks there will not be any damage to the valves/pistons but obviously the engine won't run. Remove the oil cap and while someone turns the start key watch the cams to see that they are moving. Have you checked compression?

In order for the engine to run you need air, fuel and fire -and in the right order-. Are you getting fuel at the rail? Are the plugs firing? A quick way to determine if the issue is fuel or fire is to squirt a blast of Carb Cleaner ot Starting Fluid into the manifold and try to start it. If it's lack of fuel it should run for a bit depending on how much stuff you sprayed in.

It it fails to start then it's an spark or timing issue.

And, DO NOT JUST THROW PARTS AT IT guessing that it could be this or that... If you still have the old motor there is your source of "known good" parts to try with.
 

pcb

The Diagram Dude
:
2002 MP5
It's the fact that he says "It starts but dies immediately" that has me thinking of the crank sensor.

So, in a way, it's a spark issue but it's the ECU that's killing the spark.

It's happened to a few others on this forum.

You can also remove a plug and lay it on your valve cover (with the plug wire connected) and check for spark.

If you get two or three sparks then nothing, it's most likely a lack of Crank sensor info.
Especially if it does it over and over each time after the key is turned off.


I remember a couple of people where their sensor wire had worn through to the valve cover and would short out the signal.

It was only touching intermittently and the car would instantly die.
The wire was worn through at a spot where he couldn't see it.

There is a code for the Crank sensor but it never came on.
That code is useless because the car always dies before the ECU can register the code.
 
Last edited:
:
protege5
If I remember correctly, the routing of the harness for the crank sensor is kind of crappy. Very easy for it to get rubbed through or broken. I'd start there. It's easy to check.
 
True, but if the timing wheel was removed and put in backwards it will do exactly the same; we get that question at least once a week in the Miata forum.
 
I see.... weird, basically almost the same block. Mazda builds cars "from the parts bin", ie they don't usually design parts specifically for a model if they already have a usable one already designed....

In a pulled off and transported motor -god only knows how, the chances of breaking / bending a couple of the nubs are good.
 

pcb

The Diagram Dude
:
2002 MP5
... Mazda builds cars "from the parts bin", ie they don't usually design parts specifically for a model...

I wish they were sent a parts bin full of wiper stalks from Ford.


We really should have variable intermittent wipers...






I broke my stalk off my parts car in protest. Lol



 

i12drivemyMP5

___ 323F ___
Contributor
We really should have variable intermittent wipers...



This is funny, I'm waiting on variable int stalk from 03-08 Matrix right now that is plugnplay for my 04 Scion xB that didn't come with them either................did add it to the P5 as well long ago, IIRC was from Tribute.
 

pcb

The Diagram Dude
:
2002 MP5
I personally love the Miatas with dark red that seems to have copper and brown tints to it.

My car is fire truck red. lol
 
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