-   GT S197 General Discussion (
-   -   Engine Knock? (

rangerheave 06-08-2011 07:00 PM

Engine Knock?
i own a 2010 Mustang GT with 8,200 miles on it. Since Ive bought it, I have added JLT CAI, Bama tune, Flowmaster axel back and 3:73 gears.

Ive noticed recently that when the tach gets to just above 4,000 RPM's i hear knocking coming from the engine. Almost like a fast ticking sound.

Assume I am the biggest mechanical moron you have ever spoken with and fill me in on possible reasons why this would occur.

Nuke 06-08-2011 08:16 PM

You could be running the incorrect octane or your local fuel is suspect or your tune is incorrect or a host of other reasons. Try loading a lower octane tune or tank-up with higher octane fuel and see what happens. Remember: when trying to use a higher octane fuel, you'll need to drive about 10-20 miles before the higher octane from the tank makes it to the engine immediately after filling the tank.

rangerheave 06-09-2011 05:51 AM

Thanks for the reply. I have been hoping I may have just gotten some bad gas and not something internal to the motor. I filled up this morning with 93 Octane so we'll see how things go over the next couple of days.

Nuke 06-09-2011 06:50 AM

If it continues to knock with the new fuel, load a lower octane tune. It's not too uncommon for fuel in certain areas to be a bit "off" of their rated octane. It's posible you may just need to pull a degree or 2 of timing with the tuner. Altitude can play a role as well as other things. % ethanol doesn't always help, either.

siggyfreud 06-09-2011 08:30 AM

I would think ethanol would help due to its higher octane, despite its lower energy?

Nuke 06-09-2011 08:36 AM

I'm not familiar with how the guys that write the tunes deal with that; the potential to be running straight fuel vs. fuel with "up to 10%" ethanol.

ski 06-09-2011 10:20 AM

I read that E10 fuel is supposed to have the octane rating specified at the pump.
That said, it involves a mixing process, which can lead to an incorrect blend(intentional or not).

Burns331 06-09-2011 03:36 PM

I doubt its octane, i would be looking for another issue to cause the tick

MurderedStang 06-11-2011 12:05 PM

I'm not sure if this is a correct response but I'm in FL and we have a FEW places that sell gas with no ethanol, it's more expensive but maybe you have a place where you live?

Daniel98GT 06-11-2011 01:01 PM

An exhaust leak can sometimes make a ticking sound at certain rpms.

rangerheave 06-11-2011 10:36 PM

well, after filling up at a different gas station with 93 octane, the problem seems to have gone away. Ill continue to monitor it and see how things go. Thanks for all your replies.

flguy 06-14-2014 06:45 PM

I have a 2007 GT and just installed a Ford Racing intake with 93 Bama tune. I am experiencing the EXACT same thing right now...knocking above 4k rpms. I have been using 93 octane since the day I bought this car. I go to the same station 98% of the time. Could it really be selling me "bad" gas? I'm really disappointed. Hate to downgrade the tune to 91 just because of my station (Exxon). Just paid $800 for the CAI and Bama tuner and pretty much the only difference from stock is I have a knocking problem now. Btw, I tried both the Street and Performance tunes. Any ideas? Thanks.

moosestang 06-14-2014 07:03 PM


Originally Posted by Nuke (Post 7576266)
If it continues to knock with the new fuel, load a lower octane tune. It's not too uncommon for fuel in certain areas to be a bit "off" of their rated octane. It's posible you may just need to pull a degree or 2 of timing with the tuner. Altitude can play a role as well as other things. % ethanol doesn't always help, either.

I had a 93oct tune from brenspeed and it would always ping in the summer. I eventually ran their 91oct tune with 93 oct gas and bumped the timing up 2 degrees and it never pinged. I would also recommend lowering the timing with the tuner if it still does it.

flguy 06-22-2014 05:45 PM

Just had all my spark plugs replaced by the dealer, and had the fuel injection service, which included a new fuel filter. Still pings between 4-5k at WOT. I put in a fresh tank of 93 from a different station this time (BP) in stead of my normal Exxon. Still pining. So I ran the Bama logger and sent them the data. We'll see. I am tempted to adjust the timing myself but now that I've had all this service done, I want to see what they say.

By the way, with only 27k miles on my car even the Ford guy was like "really?" when I told him the tuner guy said I should try changing my plugs. Well, it turns out it was a good thing I did. He said there was rust on the tips of the plugs. I was a little surprised with so few miles but he said it's an age thing, and if I don't drive the car A LOT (which I don't) then moisture can build up in the combustion chamber and cause the rust, so I learned something new!

flguy 06-30-2014 01:31 PM

Bama sent me a revised 93 octane tune and it seems to have cleared the issue. So no complaints now. The tune is nice, car definitely feels more responsive with that and the new CAI.

One thing I noticed is that my cooling fan is running all the time now. Since I drive a convertible it gets kind of annoying after a while every time I pull up to a light or leave the car running while I talk to someone.

Does anyone know what the stock "high temp" fan temperature is? Is it safe to mess with that now that I have a new tune? I drive the car very sanely, almost never WOT, and would really like to put the fan temp back to whatever it was. Thanks.

Derf00 06-30-2014 02:06 PM

Had the same issue with both items on my 08. For timing, here in AZ during the summer I typically leave the 91 octane tune but dial back the timing by two degree at the 4000-6000 RPM range (I leave global alone).

For the fan, I too had AM put the fan back to OEM shortly after getting their tunes. They always run here in AZ if I let them set it.

I don't recall what the OEM settings are though. It's been too long.

flguy 07-01-2014 01:37 PM

Thanks for the idea. I called Bama and asked them to put the high speed fan setting back to normal. They sent a new file within a few minutes, and it worked. Strangely, though, when I look through the confirmation screen on the tune, I still see the same number of degrees for both high- and low-speed fans as the previous tune. If he reset my fan back to stock, how come those numbers on my handheld tuner are the same as before? And why wouldn't Bama just tell me to dial in a different setting on my own? Just curious.

All times are GMT -5. The time now is 10:43 PM.