I have real problems with this car miss fires lose of power, rough idle. Could this be the 93 octane gas with ethanol in it. I have another post that tells the story on this car. Help solve this on and you are the official jaguar tech. At least in my eyes!

 

You'll have to give us some more info.
What year is the car? Are there any codes?
You can get Autozone to check for codes.

 

Heh heh. I've gotten to the point where I dread the mere mentional of "ethanol"! It's become so politicized. I think some guys would blame ethanol if their girlfriend got pregnant :-)


Cheers
DD

 

I can see this line being used on the Maury show...

 

In a word, no. There's probably more myth and misunderstanding about E10 gas since Algore invented the internet and global warming.

 

Split vac line, coil problem, could be anything. Need more info OP.....link your other post (although is dual posting for the same problem a faux pas?)

 

Ethanol is out jaguar specifically states you must use 93 octane gas no ethanol in this high performance car. Now this car runs like a champion. Give you girl a preganacy test, when must have ethanol in her you are not aware of! Tally Ho!

 

Actually- it says neither of things you claim. Here's a cut/paste from page 4.54 of the owners manual:

"Unleaded fuel
All vehicles are fitted with a catalytic
system and can only use unleaded fuel.
Unleaded fuel must be used for the
emission control system to operate
properly. Its use will also reduce spark
plug fouling, exhaust system corrosion
and engine oil deterioration.
The preferred fuel should have an octane
rating of at least 95 RON (Research
Octane Number).
‘Super Green’ Plus 98 RON unleaded fuel
(where available) may be used as an
alternative to the standard 95 RON
unleaded fuel.

Some countries have only 91 RON fuel
available. The vehicles in these countries
are specially calibrated to use this fuel.
Using unleaded fuel with an octane rating
lower than recommended can cause
persistent, heavy ‘spark knock’ (a metallic
rapping noise). If severe, this can lead to
engine damage.

If a heavy ‘spark knock’ is detected even
when using fuel of the recommended
octane rating, or if you hear steady ‘spark
knock’ while holding a steady speed on
level roads consult a Jaguar Dealer to
have the problem corrected.
Failure to do so is misuse of the vehicle,
for which Jaguar Cars Limited, is not
responsible. However, occasional light
‘spark knock’ for a short time while
accelerating or driving up hill, may occur.

Fuels containing alcohol
Caution: Take care not to spill fuel
during refuelling. Fuel containing
alcohol can cause paint damage,
which may not be covered under the
warranty.
Some fuel suppliers sell fuel containing
alcohol without advertising its presence.
Where uncertainty exists check with the
service station operator.
Note: Some difficulty in starting may be
encountered when using alcohol blended
fuel.

Ethanol
Fuels containing up to 10 per cent
ethanol (grain alcohol) may be used.
Ensure the fuel has octane ratings no
lower than those recommended for
unleaded fuel. Most drivers will not
notice any operating difference with fuel
containing ethanol. If a difference is
detected, the use of conventional
unleaded fuel should be resumed"

Mine's been operated on E10 of varying octane levels since the day I bought it, no problems whatsoever.

 

"Most drivers will not notice any operating difference with fuel containing ethanol. If a difference is detected, the use of conventional unleaded fuel should be resumed".

Does that not suggest that Jaguar is aware of a possible problem with ethanol? Patrissa did as Jaguar suggested and everything now seems OK.

 

Doesn't ethanol provide less power? Only some drivers would notice and Jaguar probably mean that.

 

They didn't say 'problem' they said 'difference'. Based on my own usage of E10 and many others here, no one has yet reported a verifiable difference never mind problem. None of the issues the OP reported can be attributed to E10 usage on an S type or any other car. Don't forget that while E10 might be new to some areas, much of N. America has had it for 20 years or more. I know that the Seattle area has had it for 30+ years. The big 'sky is falling' fuss started a few years ago when stations were forced to advertise the ethanol content. Many people who had been using it for years without knowing mysteriously developed the habit of blaming anything and everything that went wrong on E10.

Ethanol contains about 70% of the energy of gasoline. This means that E10 contains about 97% of the energy of pure gasoline. This translates into a potential 3% loss in HP and/or fuel economy. This in turn represents a maximum loss of about 9 HP under WOT at red line on the NA V8 versions and just under 1 MPG under steady state cruise on the highway. Given that the 'seat of the pants' dyno can rarely detect a loss of under 20HP, and a 1 MPG variation in mileage gets lost in normal scatter from one tank to another, Jaguar was quite correct in saying that most drivers will not notice a difference.

 

Thanks - it's what I understood them to be meaning. I'd no idea the actual figures, though!

 

When Jaguar says "resume use of conventional fuel", I assume they mean that the "difference" noticed with ethanol is undesirable. In any event, 3% of HP on a 400HP STR engine amounts to a 12HP loss of power. People on this forum spend hundreds of dollars just to achieve similar HP gains.

Worst situation - running out of gas. Next worst - only regular available. Next worst - only E10 available.

 

To be specific- that's 12 HP while at wide open throttle AND at engine peak HP level (near as damned to redline). Losses at any other condition are going to be exponentially less. This means, in addition to the insensitivity level of the seat of the pants dyno, that NO difference will be apparent to the vast majority of drivers who measure 'power' by initial off-the-line acceleration and throttle response.

As for people spending big money on modifications, never underestimate the power of the placebo effect. The aftermarket hot rod parts business depends on it.

 

Forum members with Mafioso intakes, pulleys, x-pipes and hi-flow cats, please note. It may just be a placebo effect, especially at WOT.