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3.9 discovery idling rough,blowing black smoke and no power


Shanrad

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Hi i have a 1994 3.9 discovery

Since putting new gaskets in ive had nothing but rough idle no power and black smoke. It has new coil,leads,plugs and stepper motor.we have done a compression test and all is good. One thing i did notice is it idles a little better when i disconnect the MAF plug.we also checked the spark and timimg. Any help would be absolutely awesome

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How do i check this? Once again it's back to not starting. 1 month of no idea whats happening ? ive just installed a new distributor and ignition module today with no change. When i done the head gaskets in removed the gas set up. Could this have upset anything? I was told that it wouldnt but iam now second guessing that theory

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All plugged in the correct place and whatnot? If the ECU is throwing tonnes of fuel in it's likely reading one or more of:

- Engine too cold (temp sensor)

- Air too cold (sensor in MAF)

- Too much air (MAF itself)

Could possibly be affected by throttle position sensor too. I'd super double check all wiring, plugs, hoses, etc. if it was fine before you disturbed it.

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Checked that mate..shes all good.

Anybody know first hand how to check the maf reading with a multimeter? Iam unsure of how to use this device correctly and what settings to have it on. Ive put the red lead into the vma socket and the black into the one that has no label and turned it onto v 20 setting. I then turned the key on,put the red into 35 on the ecu plug and earthed the black but its reading 11.79 which tells me its definitely not right lol. Any help would be awesome. Iam still leaning this side of the discovery and enjoy learning. Cheers

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