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VP Ignition/ Engine Managment Problems

old cars rule

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Hi,
I'm a new member trying to fix up my beloved VP.
Bit of history; Still running the original mechanicals after all these years & was until recently a gr8 car.
Had LPG fitted in late 07 professionally & it still went well, even when towing.
On a recent country trip while towing I had the typical Aussie accident, argument with a western grey kang.:(
Result: 1 guard, 1 door & 1 aerial binned. But the car still got me there, it was the return home where the problems started.
Leaving Melb running on LPG,there was an almighty BANG.
On quick inspection realised that that air-box had blown completely apart & the tubes for the intake were not in better condition. Quick patch up & back on the road. Only to find out that it would no longer run on LPG & while having to use Unleaded was like driving a truck. No economy or acceleration what so ever.
Finally got it home & the car wouldn't drive up a sloping road, without stumbling, coughing back & eventually dying.
But would idle & free rev. Put it in drive - stumble, cough, back fire & die. On both LPG & ULP
Reverse seems to work ok.
Cars not over heating.
So I replaced the following; ECU, Coil pack, Crank sensor, Map sensor, Plugs & Leads.
Still getting the same results.
Checked the ALDL with the paper clip & get code 12 No problems.:yeah:
Can anyone help me with some ideas on what could be the problem.
It starts & revs but stumbles in drive & dies when put under load like light acceleration away from a standstill.
I don't want to take it to a dealer as they charge too much for too little just to tell you what's wrong, then bankrupt you with the cost of parts & labour.
 

delcowizzid

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maybe the fuel reg took a hit from the explosion as well pull the vacuam hose off it and make sure no fuel comes out. or inlet air temp sensor but it should show a code on the ecu.
 

old cars rule

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Well I checked for vac leaks with the squirt bottle, No leaks detected.
As for the fuel reg? LPG or Petrol? will be getting that looked at this week by a mechanic.
The only sensors not changed are the throttle position & the air temp units.
Thing is I might as well buy a replacement throttle body with good sensors & replace the lot if it's that.
I was just hoping someone might have an idea on getting hold of or building the tester cable & accessing software that will give me answers.
The simple code system test still gives the code 12 so I'm at a loss.
 

Vt-Brrrlina

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what sort of gas system was put in -- if it was an impco system check the diagpragm inside the mixer - that can cause problems for both gas and petrol and other thing is depending how much u actually use petrol the injectors maybe all blocked up from lack of use causing problems too
 

old cars rule

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LPG kit is not the impco.
It was professionally installed. So I will be sending it to an Auto elec that does lpg conversions as well. That way I can hopefully cover all the bases & get this fixed. I just hope its something simple & not too costly
 

old cars rule

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Just as a thought.
The car will reverse up a steep hill no problems & will respond to heavy accereration but put it in drive & it just wont accelerate at all without the stumbling.
Could this be caused by a transmission problem?
I sort of tortured the trans with the effort of towing a loaded car trailer to & from Melb in 40+ weather.
The fluid was not the best when I got home, blackish & not smelling too good.
Could I have damaged an electric/electronc component.
We've done a service & checked all the internal connections but could the internal sensors be stuffed??
 

old cars rule

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Thanks to all for the help offered, the problem has finally been fixed.
The incident with roo started the problem with one of the LPG components loosening up from its mounting screws.
The screws are also an earthing point.
This in turn caused an intermittent earthing fault allowing the injectors to fire.
That combined with several faulty wires going to the dying coil pack caused the back-firing & other ignition problems.
So all in all it took 3 days with an Auto Electrician to back track the faults & fix everything.
Car now runs excellently so I just have to replace the airbox. Trans seems ok for now, with the extra cooler so I'm back to keeping it going.
Again thanks to all.
 
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