help my car is sick and doing weird things

[donnajc]

hi i am new here looking for answers or suggestions on where to start looking for a solution to my cars problems.
my car starts first time everytime always. (love my car) but for a while now it starts surging about 5 minutes after starting and sounds like it is suffocating and then it shudders when at idle and often just dies. Then sometimes it will start again and other times it just winds over but wont start. sometimes it runs good for a day or 2 but then starts doin the same thing...surging, rough idle, die. my fan keeps kickin in and out all the time too and this seems to coincide with the surges. have had it to mechanic and replaced the fan switch thing. ran ok for 2 days and then back to same old thing. my fuel consumption is crazy too. went from 600ks down to 300ks per tank. (i never run it out though). my car is gas/fuel. I have had the throttle body thing cleaned by my gas conversion mechanic and that helped but again keeps goin back doin the same thing. It is becoming dangerous in traffic as i never know when it is just goin to conk out. 5 times it has died in the middle of traffic lights and just had enough coasting speed to make it to the side of the road.

[VR_Acclaim]

does it do it on gas mate? it could be your fuel regulator, that exactually what mine done and it was the fuel reg

[gem05]

I dont understand why all these mechanics can never figure out what the problems are when you take the car to them.Agree with VR_Acclaim fuel reg,O2 sensor,CAS,fuel filter,what you need to do is give it a good service-plugs,leads,new coils,oil change.Is the gas conversion connected properly?

[FstStig]

Seriously if one more person calls a service a tune for these commodores, I' am going to lose it. A service is different to a tune. GET IT RIGHT!

[gem05]

My bad new to the forum and I didnt know how sensitive you are about tune ups and services but I do know the difference well I think I do,can you refresh my memory to what the difference is please.

[Brett_jjj]

Try checking your error codes to make sure everythings ok with the engine management systems etc,its simple to do this test,heres a link to a post that shows you how its done,theres some good pics on there too if you scroll down near the bottom of the page in the link..
---Checking error codes VR/VS (Revised)---

[vs2DSIRE]

Crank angle sensor i recon mate

[MPS2NV]

Lpg can be super hard on your ignition system, assuming that your car runs crap on both gas and fuel I would suspect either your dfi module and possibly cas. Surely your mechanic would have noticed if there was a more serious prob with your car.

[donnajc]

have had lots of problems with my gas/fuel switch. had it replace about 4 times in the first 12 months. hmmm thought he had finally got it right. might need to pay another visit. Thanks heaps. makes sense too. when i try to restart it i have to turn key on and off about 3 times before it starts. much appreciated ta

[donnajc]

hmmm this crank angle sensor came up alot when i googled why my car was running wierd. No 2 thing to check out. thanks alot. wish i could return the favour with info but alas im not real cluey with motors :-)

[donnajc]

my ex was my mechanic so now he is an ex i am on the hunt for a good mechanic. in the mean time i went to the one closest to my work. and if i think it is my gas i take it back to where i got it converted. Thank you. much appreciated.

[donnajc]

thanks. when i try to open it it says cannot be found. ta :-)

[donnajc]

thanks guys for all your advice. saw my mechanic today and he is ordering the crank angle sensor thing. he also agreed that he thought that could very well be the problem. i replaced the big round thing in front of it not long before it started playing up. now that was scary.... what a horrible noise when that fell apart :-O