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V8 running lean

Walkers Bay

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Hello, long time lurcker, first time poster.
So long story I picked up a vs Calais 5L v8 auto for 4 boxes of beer about a year ago.
No oil pressure, trans suspected blown, diff maybe gone, bald tires, lowered mags etc. 12 months later and far too much money I have worked through every issue and it's got a WOF and registration.
The big problem and the one I can't figure on my own is it runs lean and pops, has no power and generally goes doggy as soon as it gets warmed up.
I've checked off timing, dizzy cap, vacuum lines, all plugs are on. Tried another Map senson and replaced the vacuum line to it.
It was throwing a 33, high map voltage and 44 running lean 02 codes

If I pull the plug off the temp sensor it goes back to normal running.

Any ideas?
 

losh1971

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Just clarifying with the temp sensor unplugged it doesn't lean out?
 

_R_J_K_

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When was the last time you replaced the fuel filter? And leads?

What colour are the plugs? Could possibly be a FPR issue. Would also check the plug gaps and check just to make sure they're the right ones.

Also, open the ECU and make sure somebody hasn't thrown in some ebay special memcal.
 
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losh1971

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Walkers Bay

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When was the last time you replaced the fuel filter? And leads?

What colour are the plugs? Could possibly be a FPR issue. Would also check the plug gaps and check just to make sure they're the right ones.

Also, open the ECU and make sure somebody hasn't thrown in some ebay special memcal.

The filter is new, I've been in and replaced pump with a spare I had so I know the strainer is there.
Plugs are new, I haven't checked the gap but I will add that to the list tomorrow.
The leads I have been through with a multi meter and tested.
I have also changed out the computer and checked the chip. I have a spare away getting the vats removed to eliminate that too.
 

Walkers Bay

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replacing the temp sensor didn't fix it?
I haven't replaced that yet, my logic was if it was reading to low it would stay in open loop and run rich, if it read to high they tend to richen the mix to compensate.
Do you know the specs for ohms testing these?
 

losh1971

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Sorry mate wouldn't know the specs. If i have issues with a temp sensor i would normally just throw a new one in and not bother testing with a MM. @BlackVXGTS is pretty good with stuff like pages from the VS workshop manual. Hopefully he sees this and can give you the info.
 

losh1971

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Just for the record if those plugs are not gapped right i wouldn't recommend trying to regap them as the ground strap can sometimes break off if the plugs have already been in the engine.
 
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