[No36]

Howdy,

I’m a relatively new owner of a 1999 2ZZ-GE manual Celica. It’s decided not to start for me. Seems to be a fuel related issue – with the ECU not running the fuel pump. Cranks and has spark.

The fuel pump does run briefly at key off but not when cranking/ignition.

EFI fuses have power and the EFI relay activates with ignition.

The COpen relay has power to it, but doesn’t activate. Bridging the outputs will run the fuel pump, but car will still not start. (I presume that whatever reason the ECU is preventing the COpen relay from closing is also not running the fuel injectors).

I thought about crank angle sensor, but it has spark, so I assume the CAS is ok.

I’ve swapped out the ECU – no change. There is no break in the wiring between the ECU and the COpen fuse box.

Does anyone know what inputs the ECU uses to turn on the fuel system? I’d have expected it to use the crank sensor, but I’m new to Toyotas and maybe there is something I'm missing. Is the cam sensor used for fuel and crank for ignition or something like that?

Thanks in advance!

 

[Sea-J]

Does it fire up if you spray starting fluid in the intake? If it does than that confirms your fuel delivery issue. Simple things first so you don't "over think" the situation. When was the last time the fuel filter was changed?
I'm the first to admit I know nothing about the computer angle on these engines and I wind up throwing a lot of money at parts that are perfectly good only to find something really simple like a bad ground, loose/broken wire, etc. Suggest you might clean up all the related wire connections especially the ground wire to chassis. These gremlins will sneak up on older cars.

 

[No36]

Starter fluid - I have not, good suggestion. I have checked the injectors, they have voltage but appears the ecu is not switching the earth to make them work.

Earths.. That's a good suggestion. I'll have a look and see if something has happened there. it was washed not long before it refused to start so maybe some water got in somewhere.

 

[Corolla157]

Starter fluid - I have not, good suggestion. I have checked the injectors, they have voltage but appears the ecu is not switching the earth to make them work.

Earths.. That's a good suggestion. I'll have a look and see if something has happened there. it was washed not long before it refused to start so maybe some water got in somewhere.

Hi I have the same issue and was wondering if you ever found the issue?

 

[No36]

The issue was inside the fuel pump housing - there is a one way valve and an o ring. I can't quite remember what had broken, but it was in there. Once I fixed that it worked perfectly.

 

[Sea-J]

Whoo Hooo!
Glad you found your issue. Must have taken some digging to find that. Good information for the rest of us. Thank you.