Astra G 1.6 8v

Hello all,

Any1 know the location of the coolant temperature sensor on the X16SZR
engine. I'm thinking of fitting a resistor to it to advance the timing so
that car runs better on LPG.

Ta

 

These engines normally run well on LPG without any modifications - what is
your problem with it?

 

Well, it runs OK on lpg - its just that it runs slightly better when cold.

I believe that LPG needs the ignition timing to be advanced to get best
performance - for a cold engine the ecu advances timing (which is what I
want) and keeps the injector on for longer (which is not a problem as the
injector is switched off anyway).

If I fit a resistor then the ecu will think the engine is cold all the time
and the timing will be perfect for lpg. The only symptom is very slight
hesitation on LPG when accelerating which is not there when the engien is
cold.

 

For what its worth, you can get kits specifically designed to remedy this
very problem. I dont have any links to hand (I suggest you google it) but
they are designed to assist dual fuel operations. What you are suggesting
will impact on the warm running of the engine on petrol. I mention this as
some advise running 1 tank of petrol to every 3-5 tanks of gas.

Oh, incidentally, the reason ignition needs to be advanced if anyone is
interested is that propane (LPG) burns slower than petrol does, so it needs
to be 'cooked off' earlier to reach maximum combustion at TDC (or
thereabouts).

Mike

 

Yep ive seen those systems - but im thinking - insert a switchable resister
in between the collant temperature sensor and ecu - so when on lpg it is on
and when on petrol it is off. Somekind of switch on the dash would suffice.

I try not to run on petrol - so most of the time it will be on lpg.

What do you think?