All,
I've been having a problem with my Range Rover of late. The engine is
a 1986 Range Rover V8 with a John Davis Motorworks 4.8L conversion
fitted with Chev valves, Haltech F3 computer, bigger injectors etc.
On cold start, the engine stalls on the first start but continues
running on the second start.
After warming up, if i stop the engine and restart, all is OK. But if
I leave it half an hour or so, on startup, the engine stalls or dies
to almost nil revs, picks up to normal idle, almost dies again, speeds
up to normal idle etc. This goes for about 6-7 cycles before
stabilising with a slight hunt in rpm. It is like it is a heat soak
problem but the air flow or water flow stabilises it.
However, if I disconnect the vacuum line to the fuel pressure
regulator, the problem largely goes away.
I have replaced the fuel filter, run injector cleaner thru the engine,
replaced both the water temp and air temp sensors for the Haltech ECU.
I've checked for air leaks in the plenum (I removed it and resealed
it), I've checked for
blockages in the plenum and cleared all air passages, I've checked all
hoses for leaks etc.
I've measured the fuel pressure and meets spec. and doesn't fall
quickly when the ignition is turned off so the fuel system is holding
pressure OK.
Because the engine is non-standard, I haven't replaced the fuel
pressure regulator as I'm not sure if it is non-standard too.
How can one pick if a pressure reg is faulty? Or does anyone have any
ideas or suggestions? Anything would be helpful. I may have to pay a
mechanic soon!
Regards,
Ron Beckett
Emu Plains, Australia
'86 Range Rover 4.8L auto "The Last Aquila"
check my web site at www.users.bigpond.com/hillman
Webmaster Land Rover Owners Club of Australia (Sydney Branch)
Webmaster Hillman Owners Club of Australia
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