Injector wont pulse when hot under crank

[fatboyz39]

As above, we have encountered this problem over the last few days. When the motor is warm/hot, when cranking there is no injector pulse. Could it be Main relay? Ignition barrel? Short?

[Slaz]

Hey Jimmy, Congrats yesterday, was out there for a little while, Benny drove the pants off the EG compared to the others in the class, it was good to see, well done to all involved.

When you say pulse, do you mean the injector wont cycle mechanically, or with a node light, you have no signal or power at the loom to the injector?

[ECU-MAN]

the main relay does control power to the injectors so make sure its OK

also you have to check the signal from the ECU when its doing it to see if the ECU is pulsing the injectors or not.

[fatboyz39]

When cranking power drops to about 10v (tested at the injector plugs).

There is a signal going to the injectors (tested from the ECU end)

[jdmTYPE R]

ive had the same prob with a customer car injec pulse drops on crank but after spraying carbi cleaner into the manifold and got the car started the injector pusle went back to normal..... found out it was a faulty battery..

[fatboyz39]

ive had the same prob with a customer car injec pulse drops on crank but after spraying carbi cleaner into the manifold and got the car started the injector pusle went back to normal..... found out it was a faulty battery..

Faulty batter? We said it could but couldnt LOL.... We have the battery jumpers on the battery also and still done the same thing.

[jdmTYPE R]

have u tryed running more earth wires the motor??

[fatboyz39]

Yeah there are 4 earths to the motor.

[ECU-MAN]

have you checked the main relay ?

[fatboyz39]

i've check the solder joints they look fine. Hopefully there's a spare in the garage so ill swap and try it out.

[grumpy rooster]

What voltage is the ECU showing? That will tell you if it is pre or post ECU.