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Aussieyobbo16

3.9l xg problems

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xg ute has been swapped to a 3.9l efi engine from an na fairlane mated to an au 4 speed box. It runs but won't stay running unless revs are kept up and will stall when put in gear. When running on petrol it runs quite rich atm and blows black smoke from exhaust. Will start but not run on LPG. Could this be an ecu issue or something else engirely. Running original xg ecu

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when My EB was blowing black smoke off, it was due to a hose off.. vaccum hose maybe from the map sensor or PCV etc. 

i think the O2 sensor sees LEAN(due to massive air leak) and richens the shit out of it... 

 

the LPG may not run because they don't like vacuum leaks.  

that give's you something to look at until someome more familiar can chime in hopefully

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makes sense that i mightve missed one or two when i hooked it up, just cant find where ive gone over everything i can see. and being efi theres not much in the way of vacuum hoses.

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Map sensor is connected properly. Cant even get the damn thing to start now. Changed the dizzy over from old engine thinking the electrics might be the problem and still nothing. Dizzy is lined up properly but still no go. Any one got any clues 

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5 hours ago, Aussieyobbo16 said:

Map sensor is connected properly. Cant even get the damn thing to start now. Changed the dizzy over from old engine thinking the electrics might be the problem and still nothing. Dizzy is lined up properly but still no go. Any one got any clues 

 

The map sensor has an electrical plug, and a vacuum line.

 

I've found the vacuum line/s can sometimes come adrift from the manifold TEE, down low on the end of the log manifold.

Did you check there too?

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19 minutes ago, SPArKy_Dave said:

 

The map sensor has an electrical plug, and a vacuum line.

 

I've found the vacuum line/s can sometimes come adrift from the manifold TEE, down low on the end of the log manifold.

Did you check there too?

It was connected when the engine went in made sure new one went in almost exactly as the old one came out

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2 hours ago, SPArKy_Dave said:

Check obvious things, like firing order maybe?

 

Firing order has been checked and rechecked a hundred times. Found a cracked spark plug today. And thinking it's not getting enough fuel cos the gauge don't work properly and both petrol and LPG tanks are near empty 

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