Ever since I put in 87 octane my 97 snake feels extra slow

Craig Mack

Busted Buffing the Bishop
Founding Member
Mar 9, 2002
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Lake Mary, FL
Ever since that ungodly day where I had to put in 87 octane, my car feels like its not 100%. Almost instantly after I filled up with the 87 my check engine light came on. Oddly enough, it turned off about a day later, tank still full of 87. It's been 2 empty tanks since, and both times it was filled up with 93 octane. I have my timing adjuster set at 13* and have never messed with it.

Could my car still be severely retarding the timing? The car just feels like it goes flatter around 5400rpm. What makes this weirder is the fact that I have a Bassani catback which means around 5400 it should pull even harder.

I contimplated an exhaust leak, but I would hear it if there was one and everything looks secure and tight.

This is really pathetic, but I actually had a dream about this last night. I dreamed I floored it in second gear and got revv limited to 4600rpm. I was really sad in the dream. :(
 
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Reset your batter...unplug the negative for (not sure) about an hour...or overnight.

Might want to change out the spark plugs too....

I highly doubt you did any damage to the motor from one fill up as long as you weren't beating on it the whole time.
 
99SVTAddict said:
Reset your batter...unplug the negative for (not sure) about an hour...or overnight.

I just got back from the gym and unplugged both negative and positive. Will that work? I've always just unplugged them both whenever I needed to reset it and that always seems to reset it. I also have always waited 20 minutes to reboot but I'll leave it for an hour.

Might want to change out the spark plugs too...

I had a huge tune up a few thousand miles ago. Oil change, all filters changed, new plugs, new wires ($$$!), new coil packs, injectors cleaned (I think), etc. So my car *should* be running in tip top shape.

I highly doubt you did any damage to the motor from one fill up as long as you weren't beating on it the whole time.

Oh, I was nervous as hell when that CEL came on. I made sure to keep the revvs under 3500rpm and never floored it. I tried to keep throttle load to 50% or less, becuase I heard its not the RPM that hurts the engine, its the load. (ie - revving to 6000 in nuetral vs. flooring it in gear to a given rpm is worse)

I hope its my computer still in limp mode. Otherwise the only real practical way to figure out whats wrong would be a dyno-tune, and I don't wanna have to dish out the $$ for that if I don't have to.
 
doogz said:
A catback isn't going to provide noticable results, seat of the pants wise.

I would probably agree with you in WOT mode, but I IMMEDIENTLY noticed that the throttle smoothed out on the low rpm, just tugging along with this catback over the stock crimped pipes/flows.

I let my computer sit detached for over an hour last night, reattached it and took it for a spin, and it felt perkier, I haven't got a chance to do any WOT runs to back up my gut feeling since we are going to get :owned: by ANOTHER hurricane and I had to stow away the snake.

Another possibility could be that i've gotten used to the performance and once again think its slow. That feeling will never go away though. Even if I supercharged, eventually 6psi would feel weak, and i'd have to step it up to 10, and so forth.
 
If you had the lower octane fuel, you could have had detonation, and your knock sensors probably pulled the necesary timing. The CEL most likely put her in limp mode.

peace
 
01BlueCOBRA said:
once its in limp mode, how does it get back to norm?? does it itself ?? ive also notice once i get used to the performance it has now, i think its slow. i want a supercharger now =]

I hear that. Sometimes it feels sluggish from a roll. The 4.10s make it so I have to be VERY carefull which gear I select for which MPH. Optimum speed for 3rd gear is 60mph. If I try 3rd at 70-75mph It usually just revvs up and I hit redline soon thereafter. Anything over 40mph for 2nd gear is also bad news.

It makes it a PITA when i'm trying to pass people. The other day some dude was going ~42mph and I had to pass him cause my lane was merging, so I downshifted into 2nd gear. It just revved up and I barely went forward and had to shift into 3rd, which mean it took more time to pass him, and made it a semi-close call, he probably thinks all cobras are slow now :rolleyes:

Oh yea, I want a supercharger too. My car is fast by "normal car" terms, but its still hella slow to me. :(
 
01BlueCOBRA said:
once its in limp mode, how does it get back to norm?? does it itself ?? ive also notice once i get used to the performance it has now, i think its slow. i want a supercharger now =]

Eliminating the CEL will cancel the limp mode status

peace