Vauxhall Astra G Petrol (1998 - 2004) - 00 1.6 8v - Dual Fuel vehicle won't run on Petrol

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Fri 4 Jan 2008 23:32
00 1.6 8v - Dual Fuel vehicle won't run on Petrol - billygoat
Astra Club Estate 1.6 8v Auto w. LPG conversion
w reg / 2000
Engine; X16SZR

Gas was playing up so I switched between Petrol/Gas a few times and now car won't run on petrol at all. When switched to petrol car will not start, starter turns but not firing at all. But it Starts and Runs on gas ok after about 5 second starter delay.

I have checked fuel pump and relay - both ok. Doesn't seem to be a seperate fuse for the ignition system. I've checked all the main fuses and all intact.

Any suggestions on what else to look at?

Edited by Dynamic Dave on 05/01/2008 at 00:01

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Fri 4 Jan 2008 23:41
Dual Fuel vehicle won't run on Petrol - Screwloose

The emulators on many LPG vehicles cut the feed to the injector to switch over. Maybe you've got a switch or wiring fault of some kind - most conversion wiring is awful.
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Sat 5 Jan 2008 14:01
00 1.6 8v - Dual Fuel won't run on Petrol - billygoat
Yes the wiring is challenging!
Any idea where the feed would be cut or would the injectors just be disabled by the electronics? There is seperate set of injectors for the Gas.
If I disconnect the emulator is this likely to do any damage?
thanks
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Sat 5 Jan 2008 14:04
00 1.6 8v - Dual Fuel won't run on Petrol - billygoat
Also, do the fuel lines need to be primed? Is it at all likely that there is a blockage in the fuel line and how would I tell if there was.
many thanks
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Sat 5 Jan 2008 14:16
00 1.6 8v - Dual Fuel won't run on Petrol - Screwloose

If that is Vauxhall's dreaded SZR engine, then it should be a singlepoint injector.

Without knowing the layout of the wiring [and most LPG conversions are very "unique"] then how it's been wired to change over is difficult to know.

You say you've checked the fuel-pump and relay; does that mean that they run when cranking on petrol? Is petrol being injected down the throat of the throttle-body?
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Sat 5 Jan 2008 14:47
00 1.6 8v - Dual Fuel won't run on Petrol - billygoat
No- I just attached a hose to the tank (under rear seat) and that pumps petrol when cranking. I guess i need to check the throttle body. Is there normally anything else in between the fuel pump and the the injectors?
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Sat 5 Jan 2008 15:16
00 1.6 8v - Dual Fuel won't run on Petrol - Screwloose

The only thing between the pump and the injector [confirm just one?] is the fuel filter; there's no great pressure on a single-point and it's fairly easy to see if fuel is squirting out of the injector.
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Tue 8 Jan 2008 13:02
00 1.6 8v - Dual Fuel won't run on Petrol - billygoat
There is no petrol being injected into the throttle body. Am I correct in thinking the injector sits above the throttle body?

I guess this means either fuel filter is blocked, injector u/s or electrics fault.
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Tue 8 Jan 2008 13:20
00 1.6 8v - Dual Fuel won't run on Petrol - Screwloose
billy

The black feed wire to the injector plug should be a battery-voltage live with the key on. The ECU briefly earths the blue one to fire it.

The injector resistance [disconnected] should be 1.3 to 2 Ohms.

Look for sticky-taped bodged wiring hacked into the injector loom.
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Sat 26 Jan 2008 23:42
00 1.6 8v - Dual Fuel won't run on Petrol - billygoat
Hi Screwloose,

Checked all the fuel delivery and all OK.

Checked LPG emulator and found it was full of water!

Got a replacfement and all ok now.

Thanks for your help
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Sat 26 Jan 2008 23:55
00 1.6 8v - Dual Fuel won't run on Petrol - Screwloose

Thanks for the update - maybe give the new one a little umbrella....?
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