Range rover 1988 3.5 v8

[najam zaman]

I own a 1988 Range rover with 3.5 litre v8 with lucas throttle body . My mechanic recently tempered with the throttle position sensor and throttle body settings without having proper knowledge of these things, and has in the process probably screwed up the air fuel mixture as the car is now running rich and giving out black smoke. Is there any proper way for adjusting and setting the TPS and throttle body settings to original specs. I live in Karachi, Pakistan and hense there are no Range Rover dealers and probably only 10 or 12 range rovers in the entire country. Please help.

[hamrendan]

you need a $500 dollar Potentiometer guage to adjust this.. Lucas part number YWB 121. But if you don't have one handy ( and who does???) you can use a VOLT meter... If you use a volt meter to carry this out make sure its set to VOLTS.. any other setting may result in dammage to the potentiometer (PM for short ) 1) loosen the PM securing screws 2) switch ON the ignition 3) connect a voltmeter between the red and green leads at the PM electrical plug 4) rotate the PM clock or counter clockwise untlil the meter reads 290+or-20Mv. 5) tighten PM securing screws 6) re check the Voltmeter readings.

hope that helps...

[Najam uz zaman]

Are there any instructions in the service manual to properly set the bosch air flow meter on the 88 RR. My mechanic has tempered with the settings and need to be properly set according to factory specs. I have managed to get the TPS set as per your advise and performance has improved considerably. The only thing that worries me now is the air flow meter settings.

[dirtyduk]

the throttle position sensor most likley wont cause black smoke,throttle hesisation or driveability from that.the air flow meter has an adjuster screw under that little alloy plug but it really dosent do much if anything,
try the engine coolant temp sensor,at the driver side front of the intake manifold (two wires)brown plug,if you disconnect it I think it goes full rich thinking the car is in veary cold conditions,(black smoke) if you jump it it goes lean.Ive seen corrosion on the pins cause lots of trouble. also make sure the fuel pressure regulator is connected to vaccum, it goes from the regulator to the back of the plenium housing next to the stepper motor.thats probbly your problem.