1986 V12 (xjs) falls flat off idle
#1
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!986 v12 Lucas ignition with the CIE type amplifier on the intake
It's sat for a while.
It has fresh plugs, cap, rotor and HT leads. Fresh pump and filter.
It idles a little high, after check the Idle control valve I've identified that as the culprit.
The most annoying problem I'm having right now is:
It idles fine, if I apply more than about 5-`10% throttle it wants to die, as in it falls flat on it's face and feels like it wants to backfire in the intake. So if I jab the throttle it wants to completely die, not stumble, die. If I get it over 2k rpm slowly (which is smooth) it's fine.
In gear it's gutless below 2k rpm
The vacuum advance is working and connected.
Ideas where to look?
It's sat for a while.
It has fresh plugs, cap, rotor and HT leads. Fresh pump and filter.
It idles a little high, after check the Idle control valve I've identified that as the culprit.
The most annoying problem I'm having right now is:
It idles fine, if I apply more than about 5-`10% throttle it wants to die, as in it falls flat on it's face and feels like it wants to backfire in the intake. So if I jab the throttle it wants to completely die, not stumble, die. If I get it over 2k rpm slowly (which is smooth) it's fine.
In gear it's gutless below 2k rpm
The vacuum advance is working and connected.
Ideas where to look?
#2
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Check the throttle bushings, throttle blade gap, clean throttle bodies, check/repair linkage adjustment/synchronization. Grant has a write-up, possibly in one of the sticky threads at the top of this section
Next check the TPS to make sure it doesn't have a dead spot. Might be a write-up on that, too. If not, post back. You'll need a digital volt meter
Cheers
DD
Next check the TPS to make sure it doesn't have a dead spot. Might be a write-up on that, too. If not, post back. You'll need a digital volt meter
Cheers
DD
Last edited by Doug; 06-25-2020 at 11:14 PM. Reason: sp
#3
#4
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thanks guys
throttle blades I will check as suggested althoug I'd expect a stumble and recovery not a full on close to stall (which hold if I keep my foot in the same position, it doesn't recover)
I'll have al ook at the TPS
I posted here because the v12 is the v12. I don't believe any engine managment differences apply no?
throttle blades I will check as suggested althoug I'd expect a stumble and recovery not a full on close to stall (which hold if I keep my foot in the same position, it doesn't recover)
I'll have al ook at the TPS
I posted here because the v12 is the v12. I don't believe any engine managment differences apply no?
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