additives?
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From: new jersey
additives?
my car is an '88 with 76k and recommended servicing up to date. there is no mention that i can see in the manual for any fuel additives but i am hearing information otherwise. is there something i should be doing? mileage is relatively low but the car is 15 years old. any help would be appreciated. thanks chris
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From: Anaheim California
Porsche never recommended additives , they are only recommended by additive manufacturers . Most would not hurt the car doubtfull if many will help the car . All modern gasolines have additives in the mix they do vary somewhat from brand to brand . I am probably in the minority who think gas is gas ,I run what is convenient pay little attention at all to gas mileage burn regular in my cars designed to run regular . If you think you might have water in the tank the alcohol (which is most of what you find in a bottle of fuel additive ) will put it in suspension and let you burn it off . Now that all the underground fuel storage tanks are fiberglass very few bad things happen to our fuel before it makes it into our gas tanks .
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Joined: Aug 2002
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From: South Texas
MTBE is a neat little ether that's is commonly added to gasoline to increase it's octane rateing. I belive it's the 3rd mot commonly produce chemical in the US.
MTBE is also known to cause the build up of carbon deposits on the valves, which of course is bad. Most gasolines try to ballance the MTBE with detergents that remove the carbon. It can't help to run an additional bit of deteregent through from time to time.
Also, impuritys can cause varnish to get on important fuel system componets, so a little extra detergent from time to time can't hurt.
I know I do.
Detergents have been known to cure poor running.
Now, octane boosters on the other hand are completely useless.
MTBE is also known to cause the build up of carbon deposits on the valves, which of course is bad. Most gasolines try to ballance the MTBE with detergents that remove the carbon. It can't help to run an additional bit of deteregent through from time to time.
Also, impuritys can cause varnish to get on important fuel system componets, so a little extra detergent from time to time can't hurt.
I know I do.
Detergents have been known to cure poor running.
Now, octane boosters on the other hand are completely useless.
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Joined: Feb 2002
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From: Ft. Lauderdale FLORIDA
"Methyl Tertiary Butyl Ester"- I think that was the fat girl in high school~
-Now my fingers are tied in knots!
Anyway, if you go and hang out at the drag strip and ask the kids out there what they are pumping into their various Civics, Jettas, and Mustangs...almost always you will be told "Chevron".
Chevron has an additive called Techron, which is apparently quite effective. I don't know about y'all's proprioceptive sense ["seat of the pants feel"], but my rear tells me that my car runs happiest on this stuff. When I take the car down to Key West, I just pump it full of whatever is cheapest since I'm just going to cruise.
As to high octane...it will help most of our cars to some minor extent. If you have an '87 or later, then you have adaptive ignition control with knock sensors- little microphones that listen and recognize detonation and retard ignition from a fairly advanced position in order to reduce it. These ignitions will show a detectable benefit from higher octane.
-My '85 S2 has 10.4 to 1 compression and no knock sensors. Since it had no catalytic converters when I bought it, I decided to conduct a simple experiment. I drove out to the local general aviation airport with a gas can and told them I needed 5 gallons of 100LL avgas for my "airplane" which was parked at a private "airport". When I got home, I poured the 5 gallons in the 928's nearly empty tank and went for a ride. Yeehaa...I noticed nothing. And after a few days...it actually seemed to run a little rough and felt down on power. TOO MUCH octane... <img border="0" title="" alt="[Eek!]" src="eek.gif" />
As to additives, I guess some every once in a while will not hurt. I've had a high-manifold pressure miss for some time, and I've been all through the ignition and injection trying to cure. Recently someone suggested I try methanol- wood alcohol- and having run out of ideas, I did.
The difference in the car was astounding! Two bottles of cheap methanol and I was all over the place, fishtailing in clouds of blue tire smoke. Whoops...guess I figured out what was wrong-
-Of course, THAT brings to mind several other questions...
Anyway, add a little techron now and then and maybe your car will start talking to you like the ones on the Chevron commercials!
Normy!
'85 S2 5 Speed
-Now my fingers are tied in knots!
Anyway, if you go and hang out at the drag strip and ask the kids out there what they are pumping into their various Civics, Jettas, and Mustangs...almost always you will be told "Chevron".
Chevron has an additive called Techron, which is apparently quite effective. I don't know about y'all's proprioceptive sense ["seat of the pants feel"], but my rear tells me that my car runs happiest on this stuff. When I take the car down to Key West, I just pump it full of whatever is cheapest since I'm just going to cruise.
As to high octane...it will help most of our cars to some minor extent. If you have an '87 or later, then you have adaptive ignition control with knock sensors- little microphones that listen and recognize detonation and retard ignition from a fairly advanced position in order to reduce it. These ignitions will show a detectable benefit from higher octane.
-My '85 S2 has 10.4 to 1 compression and no knock sensors. Since it had no catalytic converters when I bought it, I decided to conduct a simple experiment. I drove out to the local general aviation airport with a gas can and told them I needed 5 gallons of 100LL avgas for my "airplane" which was parked at a private "airport". When I got home, I poured the 5 gallons in the 928's nearly empty tank and went for a ride. Yeehaa...I noticed nothing. And after a few days...it actually seemed to run a little rough and felt down on power. TOO MUCH octane... <img border="0" title="" alt="[Eek!]" src="eek.gif" />
As to additives, I guess some every once in a while will not hurt. I've had a high-manifold pressure miss for some time, and I've been all through the ignition and injection trying to cure. Recently someone suggested I try methanol- wood alcohol- and having run out of ideas, I did.
The difference in the car was astounding! Two bottles of cheap methanol and I was all over the place, fishtailing in clouds of blue tire smoke. Whoops...guess I figured out what was wrong-
-Of course, THAT brings to mind several other questions...
Anyway, add a little techron now and then and maybe your car will start talking to you like the ones on the Chevron commercials!
Normy!
'85 S2 5 Speed
Burning Brakes
Joined: Dec 2002
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From: Airlie Beach, Australia
Hello,
Jim is correct of course - fuel "additives" were not recommended.
Porsche's Service note 2440/8510 dated 6/Dec/1985 recommends using Chevron's TECHRON to "...clean partially restricted injectors..." They stated "...one 20oz container added to a full tank, use car until the tank is half full, refill and then add 20oz again.
Then, "...20oz every 5 tank refills or 3000 miles..."
Regards
Jim is correct of course - fuel "additives" were not recommended.
Porsche's Service note 2440/8510 dated 6/Dec/1985 recommends using Chevron's TECHRON to "...clean partially restricted injectors..." They stated "...one 20oz container added to a full tank, use car until the tank is half full, refill and then add 20oz again.
Then, "...20oz every 5 tank refills or 3000 miles..."
Regards
