Fuel Grades

[cfg83]

groar -

I only see one grade of diesel fuel in the USA (but maybe that is because I don't have a diesel car - I am not looking very hard). Can you tell me the difference in the diesel grades in France?

CarloSW2

[Will]

Some of these responses have been very interesting. I have been using nothing but regular after my engine rebuild so I could break it in on regular. I have been thinking about going with premium every few tanks to help clean it out.

I would have expected people to see more of a difference in FE between the two.

[RH77]

Originally Posted by Will

Some of these responses have been very interesting. I have been using nothing but regular after my engine rebuild so I could break it in on regular. I have been thinking about going with premium every few tanks to help clean it out.

I would have expected people to see more of a difference in FE between the two.

I'm not sure which would be cheaper, but running a tank with the "Seafoam" additive might help clean the fuel delivery system. Every year or so I run it through the brake booster line to clean the top-end. LOTS of white smoke, but that's just the carbon build up burning-off. Others recommend Auto-RX (never tried it) -- I like Seafoam because I can find it on the shelf at the auto parts store. It's great stuff.

RH77

[Will]

Do you add it to your tank or pour it in the engine like others do?

[RacerX]

That's ironic Will, I just topped off today with midgrade to see how it affects my metro. It'll take about a week to see, After that I have a couple of gallons of acetone (99%) laying around, I'll add a couple of ounces every tank. We'll see....

I run 87 in everything all the time except if I go racing

[igo]

I used mid and prem a few years ago and couldn't tell a difference from 87 in power or mpg and figured I was just wasting money. It has been regular since.

[RH77]

Originally Posted by Will

Do you add it to your tank or pour it in the engine like others do?

Both -- mostly through the booster line directly to the engine.

I perform routine maintenance and tune-ups on friend's and family's cars -- they just bring them over to "Rick's Garage". All of them get the Seafoam treatment in the tank and through the booster line.

One success story is on a low-mileage '95 Mercury Mystique 4-cylinder/auto. It's driven 5 miles/day to and from work. It was REALLY gunked up with carbon. The idle-air control valve got loaded-up and the idle speed was abnormally low -- shook the car like crazy. Either the treatment was to fix it, or replace it (difficult spot on the underside of the engine). So far, the Seafoam (and 10 miles of white smoke) did the trick.

One gunk preventer I have on the 'Teg is a PCV catch container. It's basically an air compressor moisture collector, attached inline between the PCV valve and the intake...

[bhazard]

87 in the festiva. 92-93 in the turbo cars. I think we put reg in the shadow once and it gulped it down. I kinda wanna try a tank again just to see but im scared. Its also non intercooled with cast pistons so I do *not* want to detonate with it.

[Johnny Mullet]

I use premium fuel in my car because for some reason, Christine hates regular. When I run regular, the car pings going under load and feels weak. I thought I had a timing issue at first and messed with the timing like 27,000 times and found no difference unless I went way out of specs, but this caused idle issues and other problems. I decided to run premium for the hell of it and within 10 miles, I noticed better throttle response and that damn pinging (valve clatter, fuel knock) went away. I have been running it ever since and stick with one gas station when possible.

I heard all the bull from techs about 1996 and newer cars only need regular because the PCM controls the timing, blah, blah, blah. I believe that to a point, but this does not go for all cars in my opinion.

I also figure this. Premium is usually 20 cents higher than regular per gallon. My car takes 10 gallons from empty and that would equal $2.00 on a fill. I would pay that extra so the car is not subjected to any harm. As far as fuel mileage increase goes, I did not notice a change myself when I switched, but feel more confident about what's running my engine.

If your car runs fine on regular, then save the $ and use it.

[Johnny Mullet]

One more note.

I do not use fuel additives, but I do use Seafoam. I buy a can and dump 1/3 in the motor oil when there is about 500 miles to go for service, another 1/3 into the fuel tank, and the last portion gets sucked right down the throttle body while the engine is running and my hand is on the throttle to keep it from stalling. After you get it all into the TB, shut off the engine and wait 5 minutes. Then go on a drive and watch the smoke! It may be very severe at first, but eventually clears out.

There is an old trick they use on the Crown Vic police interceptors where they spray water into a hot engine through the throttle body. Carbon cystalized in the combustion chamber will actually shatter when the water hits it and it breaks up and is expelled out the exhaust. I have done the water trick before, but I prefer the Seafoam since it offers lubricity and will not harm the engine in any way.