P38 4.6 running problems

[shiftech]

Originally Posted by 4.6 man

Hi
I did as you said, and the tickover stayed the same, when i revved the engine it got to 2000 rpm and then cut out. and as usual it took about 5 or 6 turns of the key to get it started again. when i rev it above tickover it will get to about 1500---2000 rpm and then the revs drop and it starts hunting before cutting out. Also when its running the dash lights flicker and im wondering could the solenoid for the gas system be cutting off the fuel it normally changes from petrol to gas at 2000rpm but then i have taken the main fuse out of the gas system.. ive never had such a problem with a car all the signs keep contradicting what would make sence...
Thanks
Steve

Hi steve,
The engine should run at idle with the AFM disconected.The ECU only looks for feedback after approx 550 rpm then it should go out of range and the engine cut out.not familliar with your LPG system,most dont rely on the AFM,only the lambda.So with the AFM disconected from the plenum the only thing that could happen is a loud bang.Try removing the fuse for the petrol pump,then running on gas.Killing 2 birds with 1 stone,fuse ensures your not supplying both LPG and petrol at the same time.If it runs then it looks like the AFM.
Or substitute The AFM for a known good 1

[shiftech]

Steve you have PM