Auto Stalling

[TrustNo1]

Hey everyone. New problem for me now >.<

I have dual fuel and I was driving along on LPG and my car backfired and blew out the air filter, which has happened before and this tells me I need new spark plugs which usually fixes the problem. The next time I turned on the engine the car ran really rough and I couldn't get above 50km/h. I tried on petrol and it's the same thing. So I check error codes and I get code:
35
44
64
66
76
78

So I installed new O2 sensors and new spark plugs and leads and new air filter and oil filter and oil.

Car is still running rough on both lpg and petrol. Backfires on lpg still and can't get above 50km/h on petrol. I noticed the purge valve(I think that's what it is) was unplugged near the air intake so I reconnected that and it runs a little better on petrol but gas is still bad. Would there be a vaccuum leak somewhere else?

Any ideas...?

Thanks

[TrustNo1]

Hmm on further research I'm thinking bad coil pack or CAS?

[TrustNo1]

Ok just took off each coil and tested them on 20k ohm and two read normal as in the gregories (5.5 for both), one didn't register at all. so it's safe to assume, before i go out and spend more money, that it's a broken coil? and is it worth replacing all three at the same time?

[FstStig]

Def replacing all 3 and the dfi module if you have the money, can pick them up from the wreckers fairly cheap.

[TrustNo1]

Ok thanks