Need Advice on VN Commodore 3.8 V6 Not Starting

[suzolla]

Hi,
I have 2 Commodore cars that now seem to have the same problem.

The both were running fine but have been sitting for a few months, now they won't start as they seem to flood, will initially fire and run for a couple of seconds and then stop, exhaust smells of petrol and plugs are wet. have taken out the injectors and they aren't leaking, but appear to spray alot when the engine is cranked.
The EFI does not have any fault codes showing.

Does anyone have any suggestions as to what might be the cause.

Thanks
Tim

[gimmemud]

Checked all the sensors are all plugged in, had same sort of problem when a vacuum hose had come off a sensor and have had a buggered throttle position sensor that sounded the same

[Mattman]

The commodores run a MAP sensor I believe and if that has come unplugged then the motor will think it needs extra fuel and possibly over fuel it on starting.

Matt.

[chchzookfan]

if the fuel is old that could be the problem? esp if its sat for a while same thing happened with my friends bedford van

[Slideways]

Possibly a faulty Oil Pressure Switch, on these motors its a common problem where the OPS will fail and leak out onto the plug. This shorts it out and either causes the Fuel Pump to cut in and out, or even run on with the ignition off, sometimes it'll even blow the EFI fuse.

The OPS is screwed into the alloy oil filter housing. Tell tale sign will be oil on the plug.

About $40 from repco....if thats the problem.

[mar4les]

sound like the fuel gone off ...it go all oily and sticks 2 the spark plugs and they stop working. the best way two cheak it is spill some on the concret and try 2 light it with a lighter if it burst in two frames is still good if it doesnt burn or burn slowley it needs changing and new plugs..as two the falty oil pressure swich is hocked in parrel two the fuel pump so and the plugs wet thats ok .as two the map sencer if unplug still will run but run rich and if and of the sencers are unpluged a code would be pressent .. something to work on any way i! have fix a hilux of a mates will hollden v6 was in shed for 3 months and that was the problem!

[Bolo]

I had a 93VR commodore that did the same thing , and i sent it in and it turned out to be the Ignion moudle under the coil packs and it costed about $900 , hope yours havent done that