EL problem, it is on gas But it is not a gas problem,,,recently changed the head( factory reconditioned) It ran well for a while on both fuels, then it began to miss on petrol, done all the usual checks (plugs. leads,dizzy cap, rotor arm,miles of spark . compression tested) sombody said INJECTORS, so I got a set of injectors, they didn't fix it, so then they said that maybe I had disturbed gunk in the fuel rail and it has blocked an injector, so I Flushed the rail out and replaced the filters in the injectors, put her altogeather and still have the miss in No2,and4, Runs like a hairy goat on petrol but sweet as a nut on gas. Any ideas on anything that I've not tried would be very much appreaciated,

have you checked all the rubber piping [on motor] as you may have 'disturbed' one & maybe broken it but looks ok?

no, but will do tomorrow thank you. CD.

What fuel pressure is it running? Changed the fuel filter? Does the pump have good flow? If it runs good on gas you'll nearly be looking at pump or filter...

Cheers,
Tim

I don't have access to gauges etc to measure the pressure, but it has a good flow from the pump to to the fuel rail, but I'll try any thing will get a filter today and see what happens after changing it. CD.

If it runs fine on gas, but not on petrol, it is almost certainly a fuel issue, not ignition.

You have isolated the problem to cylinders 2 and 4. How did you do that? Disconnect the injectors individually with the engine running? If you can disconnect an injector and have no effect on how the engine runs, then that injector is not functioning. Back-probing the connector while the engine is running will tell you if the injector is getting a pulse (ie, the ECU is working) - which it probably is. That would leave the injector itself as the problem - maybe stuck closed.

Have you been able to gain any clues from reading the plugs? Or do they all look as they should?

Get a noid light and make sure you are getting injector pulse to all 6 injectors, also pull the codes and see what you get.

Gab