Sorry about this post I have tried reading all the post for starting issues but man there are a lot of them!

lets see if I can explain what's going on.

swapped the y7 from 99LX into my son 98DX(major head gasket issue). the LX motor ran prior to pulling it out of the car. I drove it home. once I parked the car it had a rpm flux from 1000 to 2500 or so.

the motor sat for about two weeks. and the alternator was frozen I loosened it up and installed the motor.

which required an engine harness swap and the distributor from the dx motor

the motor would crank but not light off (start).

I can hear the fuel pump prime. I have checked there is pressure in the fuel rail and pulling the plug there is fuel in the cylinder.

I checked for spark by pulling the plug and NO spark.

the distributor turns and my valves move so timing belt is not broken.

I have not checked the timing.

I checked and clean the grounds the front one from the radiator support to the block, the frame to the transmission and the one in the harness to the thermostat housing.

I had a spare P2e ECU sitting around the same that came in the dx.

after reading issue on here I said why not.

I put the spare ECU in and the motor started ran for a little 2Mins or so start to flux then died

Now im back to the motor will crank but not light off

no check engine lite at anytime. I have not been able to check for codes.

I have a good strong battery.

anybody got a clue?

 

No spark still? If so, check whether dash fuse 9 is blown.

Does the CEL work?

 

the cel worked prior to the head gasket letting loose.

it does come on when you start the car then goes out

it ran so for a little bit so the spark must be good? (ruling out any issues like coil or distributor or timing issues)

but I have not checked it since the motor started.

 

sorry I will check the number 9. I checked under the dash that one is good 15 amp but I didn't check under the hood.

 

It works.

Check for spark at all 4 plugs with the spare ECU installed. Does the fuel pump prime with this ECU?

Have your removed the distributor cap and rotor to inspect the distributor internals?

 

not out of the normal.

my question and I guess I should have asked it was

why would swapping the ECU allow the car to start?

 

You can talk hypotheticals and theories all day long and get nowhere. Stay focused on fundamental no-start diagnostics 101 as this is the one and only way to solve the problem and get help in a tech forum.

 

ok so the number 9 fuse is good it the one under the dash right?

 

 

fuel pump primes and no spark at any plug. I cleaned up the inside of the cap and rotor contacts with a little sand paper but it did not help. there was nothing damaged or broken in the internals and the rotor turns when you crank the motor.

 

ok for those who may read this looking to solve their problems here is the fix.

I replaced the part number 06300-P2E-305 in the DISTRIBUTOR call either IGNITION KIT or IGNITION control unit.

I would like to thank RonJ@ht for all his help after going back and looking I noticed the cover to the IGNITION KIT was not sitting correctly. Once I removed it I found it was loose and water had gotten inside. I had a spare distributor I swapped the parts and it started right up. I swapped it back to the original ECU with no issues.

I did have a problem with the motor idle fluxing from 1000 to 2000 rpm. I removed and cleaned IACV with carb cleaner no more flux.

the car is headed for inspection today

thanks again RONJ