Range Rover 3.9 V8 Idle

[DORISD90]

Hi All,

I purchased a 1993 Range Rover Classic 3.9 V8 yesterday and am delighted with my new wheels. It may not be immaculate inside or out but I love it. I have a '94 Defender 200Tdi at home so I'm not new to Land Rover but I jumped at the chance to own a Range Rover. I'm new to Range Rovers and particularly V8's so If I'm not providing enough info let me know. Having a bit of trouble thus far so I thought I turn to the 'old reliable' for some info.

Thanks in advance for all your help.

The first problem I'm having is the Idle on the V8. It's 1993 Range Rover Vogue (I think, not sure what the difference is between the 'Vogue' and the 'Classic') with a 3.9 V8 and a 4 speed automatic transmission. The idle on the engine varys between 750/1000 revs and 250 revs. The engine revs fall away to 250 and then shoot up to 750/1000 revs again and its pretty erratic. This is constant when she is idling whether it's in drive, neutral or park. It doesn't matter whether the engine has just been started or whether it's been driving for a while and is warm. The engine cut out twice at traffic lights today which is extremely annoying. There is not problems starting her again or when I'm driving. I noticed today that when the air con (or heater, whatever is in my car) is on the idle sits perfectly just below 1000 revs and there is no issue, it doesn't vary at all.

If anyone has any ideas on what the problem is and/or how it can be fixed please let me know. If you need anymore details to try and diagnose the problem let me know and I'll do what I can to answer your questions.

Thanks again,

Andrew

[Roverbo]

Hi Andrew,

Sounds like a stuck idle air valve to me (my favorite repair part on the RRC ). There has been quite a number of subjects about this lately, just look at the last months posts. Good luck with your car - still loves mine, even if I sometime spend more time under it than driving it.

[Range Rover Blues]

Vogue is a better equiped car than a 3.9EFi. The term Classic was originally applied to the soft dash or 300 series mark1 range Rover, being an upgraded design. The term is now applied to any "original" shaped Range Rover ie pre P38.

[DORISD90]

I think the problem maybe electrical. The spark plugs may not be getting enough juice and therefor not producing a good spark because of a faulty battery or alternator. I was thinking of changing the coil and battery to see what happens. If I play the radio when driving and turn the engine off she struggles to start afterwards because theres no juice in the battery so that needs to be replaced anyway.

Do you think this will sort the problem. If its not the battery then maybe the alternator is not recharging the battery properly.

Any Ideas?

Thanks

Andrew

[grumbleweed]

is it gassed by any chance?

[Bowie69]

Clean the stepper and get the battery drop-tested, this will tell you whether it is goosed or you need a new alternator, I would suspect it's just the battery given your description.