'89 V12 runs like poop unless using 93 octane...
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From: Australia
I have to warn you: I may be on the verge of making an ignorant statement, but...
I don't think I have a Marelli car. I've got a single "ignition amplifier" with LUCAS written on it sitting on top of the driver's side (LH) bank of cylinders.
Jess
p.s.: I'm also watching the "my car is idling rough" thread because mine also has a shake when idling at low-rpm that goes away immediately upon adding throttle.
I don't think I have a Marelli car. I've got a single "ignition amplifier" with LUCAS written on it sitting on top of the driver's side (LH) bank of cylinders.
Jess
p.s.: I'm also watching the "my car is idling rough" thread because mine also has a shake when idling at low-rpm that goes away immediately upon adding throttle.
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Joined: May 2015
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From: bradford
yes the timing needs to be spot on for any fuel to burn correct .So if mine will burn 87 I think a 99 should also .You can go to local airport and get aviation grade fuel I think that is 110 now that has to make a difference.
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From: Kamloops BC
Only if your compression is greater than 12.5:1
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From: Perth Ontario Canada
You'll see zero difference, not to mention that almost all avgas has lead in it which will destroy the catalytic converters in short order.
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From: Pacific Northwest USA
Make a difference in.....what?
Cheers
DD
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Joined: Nov 2015
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My gas gauge clearly states "Premium Fuel Only".
The fill has a sticker on it that says the same.
You can move the jumper to go down to 87, but that simply retards the timing.
Newer cars can retard the timing automatically (no jumper). But that does the same thing.
The fill has a sticker on it that says the same.
You can move the jumper to go down to 87, but that simply retards the timing.
Newer cars can retard the timing automatically (no jumper). But that does the same thing.
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From: Vic Australia
In pre engine management systems that employ knock sensors (aka XJS), there is a minimum octane rating. In these vehicles going to a higher octane fuel will have no effect as the ECU can not adjust timing to take advantage of the increased octane. Even in knock sensed vehicles using 110 will have no effect as the ECU will not adjust timing to that extent.
In the Marelli car Jaguar incorporated an ignition strategy link to have the ECU adjust timing for 95RON. We have 98RON available at the pump but there is no difference in performance in my car between 95RON and 98RON. There is however a big difference between 91 and 95 if I change the link.
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Joined: May 2010
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From: Vic Australia
I have to warn you: I may be on the verge of making an ignorant statement, but...
I don't think I have a Marelli car. I've got a single "ignition amplifier" with LUCAS written on it sitting on top of the driver's side (LH) bank of cylinders.
Jess
p.s.: I'm also watching the "my car is idling rough" thread because mine also has a shake when idling at low-rpm that goes away immediately upon adding throttle.
I don't think I have a Marelli car. I've got a single "ignition amplifier" with LUCAS written on it sitting on top of the driver's side (LH) bank of cylinders.
Jess
p.s.: I'm also watching the "my car is idling rough" thread because mine also has a shake when idling at low-rpm that goes away immediately upon adding throttle.
Change ALL 12 plugs
Check/change all 13 ignition leads.
As a start.
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paulyling
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Dec 14, 2016 04:10 AM
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