EFI troubles maybe fuel pump

[Bond]

Ok i got the gas tuned on my EFI 4.2 gq. Whilst on the dyno they said that power is down on petrol but the emmisions were fine so it didnt seem to them like my injectros were dirty. They said that it could be the fuel pump on the way out.

Any ideas on tehir theory? How can i tell if the pump is ****ting itself? The reason i dont feel it is the pump is that it drives sh%t down low but once above 2000rpm its great, so the pump can deliver fuel when needed.

However if i turn the key i can hear the pump and it stays on for around 3 seconds. i turn the key off...wait a bit and turn it on again and i can hear the pump again. With my other cars the pump usually didnt come back on the second time until i cranked the starter as there was enough pressure in the fuel lines.

has anyone else running dual fuel encounted similar problems?

Thanks

Bond

[Bond]

No on had efi problems with duel fuel????

[CrazyMan]

well i dont have dual fuel but i noticed the same problem, Even if i turn the engine off for 3seconds the fuel pump starts again when turn ignition on again. Is this normal or suss?

TB4.2 efi petrol

[mikegq]

you are right in ur thinking. it wont be the pump. as u said there is a much higher demand for fuel at high rpm so you would think it would fail up high not down low. it is normal for the pump to prime(get presure up) when u turn the key on. the computer controls the earth to the fuel pump relay and can do what it pleases. you will probably find that if you turn the ignitoon on twice in a short period it wont prime againas it figures it must already have fuel pressure.
hope to help

[mikegq]

i would suspect your problem is more likely to be a faulty EFI component such as a 02 sensor, coolant temp sensor or dirty air flow meter
take it to an expert and get them to check it out
or if you wanna take a gamble i would say replace the 02 sensor.
mike