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V8Landy
21st October 2009, 09:38 AM
Can some one tell me where this is on a 3.9 V8i. Trying to rule out everything that can make it run rich and idle fast. Also i looked under the left side panel for ecu but could not see it(or did not reconise it) Can some one tell me what i'm looking for. It is a 91 V8i Disco ( it has a 3.9 in it) Any help appreciated Thanks Brett

langy
21st October 2009, 10:07 AM
The EFI coolant sensor is the one with 2 prongs on it, screws into the intake manifold roughly at middle front. ( The one for the dash has only 1 prong)
The AC sensors should be on the elbow near the thermostat.

The ECU should be behind the kick panel next to and a little above the accelerator - big silver box with 14 cux on it.

Katie
21st October 2009, 11:32 AM
The car may stay on fast idle and run rich if it has a wrong or stuck thermostat, should be 88deg. Also check the resistance between the first and last pins on the air flow metre, I think Land Rover set it at 250ohm I find some run rich at that and have had much better running below 4ohm.
Otherwise air leaks or leaking injectors?
Katie

roverv8
21st October 2009, 02:30 PM
3.9 v8, I just replaced mine, it's the very front sensor on the inlet manifold, this is the sensor for the ECU, not the dashboard temp.
It has a plug on it similar to the plugs on your petrol injectors.
Luke

V8Landy
22nd October 2009, 02:22 PM
The car may stay on fast idle and run rich if it has a wrong or stuck thermostat, should be 88deg. Also check the resistance between the first and last pins on the air flow metre, I think Land Rover set it at 250ohm I find some run rich at that and have had much better running below 4ohm.
Otherwise air leaks or leaking injectors?
Katie


Tested the afm, The thermostat is fine and the right temp, Not sure on the injectors so will see how i go.
Went for a run on petrol and it is not as rich as it was sense i have done the afm so it may be right now.
Thanks for the info everyone. Cheers Brett

LOVEMYRANGIE
24th October 2009, 01:19 AM
The car may stay on fast idle and run rich if it has a wrong or stuck thermostat, should be 88deg. Also check the resistance between the first and last pins on the air flow metre, I think Land Rover set it at 250ohm I find some run rich at that and have had much better running below 4ohm.
Otherwise air leaks or leaking injectors?
Katie

Its not set on ohms, its set on volts. The ECU reads a voltage output from the AFM.
And 4 ohms is almost a dead short, plus if your checking it with the plug still on, you are taking into account the line resistance of the harness and also the components in both the ECU and AFM resulting in a wildly incorrect MAF setting.

See this post. http://www.aulro.com/afvb/technical-chatter/85676-would-you-say-maf-faulty-2.html#post1092934

Cheers

Andrew