rushtona

Recently upgraded to a 3.0 speedtech exhaust and an EPL 92 octane tune. Otherwise all stock. Got a CEL while driving moderately hard but probably 10 minutes after filling up. Didnt get a receipt so not sure if 87 was possibly used to fill. (Oregon). Havent run the code but wonder if I should throw some octane booster in before attempt at limping to the shop. Advice?

Macster

Chances are you'll have to throw a lot of octane booster in the tank to raise the octane any appreciable amount.

If the CEL is steady on and *NOT* flashing and the engine is otherwise not showing any signs of trouble, you probably ok. Probably. No guarantees.

Best advice I can offer is to read the error code.

Could be something as benign as a loose gas cap.

Or when I run 91 octane discount gas in my Boxster the CEL comes on and the error code points to an under performing converter.

ztnedman1

Much easier/cheaper to just add a gallon of E85 if you need an octane boost. You wont have any issues or need to worry if you stay around a 10/1 gas/e85 mix

dubyaTT

Uhh, if the check engine light is flashing...Do not drive the car!

Kevin

rushtona, most likely had misfires in multiple cylinders..

Did you know that you bought 87 octane and then jumped on boost? If so, with a tuned file you only have 15 degrees of knock retard. If you use up the nine lives you get engine detonation. Damage occurs 100%... Tuning has increased the HP output, you have to insure that you have the minimum octane rating for your tuned file.

Problems at the pump occur, however, the second that you feel the studder or hesitation requires one to back off the gas...

If you haven't changed the plugs in awhile you might need to..

Macster

Correct. I left out the "NOT" but have corrected this in post.

Thanks for the catch.

rushtona

CEL was solid. A few codes came up most concerning was MAF sensor issue. But so far looks like a hose to intercooler blew off