Ford Explorer | Ford Explorer Sport Trac | Mercury Mountaineer | Lincoln AviatorForum for discussion of the Ford Explorer, Ford Explorer Sport Trac, Mercury Mountaineer and Lincoln Aviator. (Ford Explorer Forum, Ford Explorer Sport Trac Forum, Mercury Mountaineer Forum, Lincoln Aviator Forum)
Ford Forums is the premier Ford Forum on the internet. We discuss all Ford models on the forum. Registered Users do not see the above ads. Please Register - It's Free!
At normal highway demand (specific RPM and power output), the old pushrod motor actually has a slightly lower BSFC than the overhead cam motor. It also has more torque in the 1500 - 2500 RPM range. Not like it's a big deal, though.... your driving habits will have a MUCH greater influence on fuel mileage than the engine type.
As to the old wives tale about all the benefits of higher octane fuel.... Unless your compression ratio is so high (or your combustion chamber deposits so bad) that you're getting compression ignition, you don't need any higher octane - and backing off the spark timing won't stop the knock - the ECM will realize that it's compression ignition, quit retarding the spark, and light the "check engine" light. In normal operation, the spark will be advanced to the point where the knock detector signals the ECM, and then backed off slightly... this is adjusted constantly - and when incipient knock is determined by spark timing, the fuel grade doesn't matter.
Higher octane fuel does not have any more inherent energy than regular gasoline..... it simply has a higher ignition temperature (and a higher price).
Manifold deposits, combustion chamber deposits, injector fouling, fuel pump wear, etc. are all treated with additives to the fuel, and all grades of a particular brand get the same additives.... and even many different brands use the same stuff.
Wow!!
Totally respect your opinion but don't agree with it in any way, shape or form.
We live in two very different countries and there's no such thing as universal answers. The lowest octane fuel I can buy here is 91 RON and the highest 100 RON, and we have one of the highest contents of sulphur in our fuels out of the developed world countries. I have tried both of these (and everything in between) in all the cars I've owned and those of the people around me, and the differences in consumption are very noticeable during steady highway driving (not so much in the city), as is the amount of carbon that accumulates around engine parts.
I've never suggested that high octane fuel has more energy. If that was the case you would feel an engine power increase while driving. All it does is burn slower, and precisely because of that, more completely and efficiently. I don't know what you consider a compression ratio that's "too high" but I know for a fact that all modern cars imported, for example from Europe, suffer from detonation when using our low octane fuel, regardless of miles travelled, so much so that there are specific calibrations that had to be developed by Ford for us to correct this problem. So far, I've never seen an engine light 'on' in one of these cars while pinging, either the ones equipped with EOBD or EOBD II.
Last but not least, it would be a wonderful world if all of those fuel additives worked. The sad fact is that they don't, otherwise I'd never find engines full of crap when you pull them appart, even in those with so very few miles in them that have been looked after and serviced properly.
marc
My '98 with the 4.0 SOHC gets about 15 around town, 20 on the highway. I always use the lowest octane gas here (87). Should I use fuel additives every once in a while to help clear out deposits in injectors, valves, etc?
Hi KU
This is a bit of a grey area. I personally don't believe in additives for the fuel system. I've seen too many cases of people that after putting additives in (from many different brands), had their cars start to stall and run rough or not run at all. In some cases, the additives removed a bit of rust that had formed inside the fuel lines, and this accumulated at the base of the fuel press. regulator or at the injector filter screen or inside the fuel pump (from the return line) causing expensive damage for some. Others caused very fine droplets of water left over in the fuel system to group together and stall the car, and so on. So I decided not to use any of them and I don't recommend them to anyone.
I also know some people that will swear blind that additives are good and have been using them for years without dramas.
The easiest way for me to avoid all these problems is to run a tank of high octane every so many tanks of low octane (2-3). That way the deposits barely form at all. If I ever need to clean anything I do it off-car, ie: remove the injectors to clean them, remove the pump to change the filter screen, etc, but this is something I've done probably once in 80-100 000 km. I've also used carbon cleaner sprays to clean the intake manifold, valves and throttle body and it worked ok, but I know that not everyone is keen on removing parts to clean them and the easy way out are additives. So the choice is yours really.
To inspect and have a general idea of how much carbon deposits your engine has, remove the air intake tube that goes from the filter to the throttle body, open the butterfly and have a look. If it looks clean, then more than likely the internals of your engine are also clean. You can also tell by removing the oil cap and looking at the camshafts and valves, as carbon will also find it's way into the engine oil. If they look clean and not covered in a dark/thick layer of crap then the engine is clean. As for the fuel system, the best indicator of how good or bad is always the fuel filter. cheers
marc
thanks for all the info. I think I'll steer clear of them. I've heard of that higher octane fuel every few gas tanks idea from some people, but I've also heard that once you put in higher octane you may have to continue to put in that higher octane? I can't remember the reasons though. It wouldn't seem to be the case to me, but I'm no fuel expert. I've also heard that stomping on the accelerator every once in a while to get the RPM's up helps burn off buildup as well. So many ideas floating around out there.
Either way I'm not sure. With my old car I used fuel additives maybe twice and same with the higher octane in the 5 years I had it. For the last year it had a stalling problem while braking at about 5-10 mph. I never had it diagnosed (correctly anyways), but the more I've been thinking about it the more I think it may have been fuel-related with rust or whatnot coming loose, or whatever. But I can't say either the additives or higher octane caused it.
Either way I think I'll just keep what I've been doing with my explorer, just putting in 87 every time. It's got 150k miles (only 3k by me) and it's not broke so I guess I won't try to fix it.
Whats the best miles per gallon you get with your Car?
I can get up to 32 with my 99 Eddie Bauer Explorer (V-8) if I drive right at around 48 mph.
I got 18.8 mpg on my 96 eddie bauer explorer on a 2300 miles trip from Texas to Colorado. Speeds ranged from 45 to 86 mph. Since a replaced the spark plugs to the 3 electrode kind the gas milage improved by 1 mph.
I'll post what I have:
2006 F-150 Ext Cab 4x4 Lariat 5.4L 3.55 gears. 15.2mpg combined I routinely drive about 75 or 80 on the highway.
2005 Ford Exp XLt v6 4wd. Fully loaded for vacation driving, 20 mpg
2006 Toyota Avalon Limited. 32mpg loaded from NJ to WV.
I care for a fleet of 13 E-350 Vans. They get anywhere from 12 to 3 mpg. The difference is entirely based on driver behavior. The 6.8L V10 version only costs us 1 mpg over the 5.4L V8. Idling, it seems is the key to the difference.
Linear Mode
