coastalS197

Hey all, its my first post, hoping it wouldn't be such an urgent one.

I took my 2007 mustang GT, bone stock down to the paper air filter in to get the rattling noise fixed, which was due to a plate between the transmission in the motor that rattled. I got the car back and the rattle is still there, and it is definitely a spark knock at wide open throttle. Gas is not the problem its been this way, and its more apparent when cold. I'm at 35,9XX miles and warranty it about to expire. Its at dealership now, and since I would hardly trust a dealership to tie my shoe's, since I was the one who diagnosed the plate in my transmission and brought in the paperwork that stated the fix off of this site.

Has anybody had the spark knocking problem? That fades away as the motor heats up. My guess was to tell them to retard the timing by just a degree or so not to reduce performance. The genuine mechanic said he could only retard or advance on the comp. screen he couldn't pick by how much.

I can rule out fuel filter, bad gas. Thinking maybe coil over plugs? Any help is appreciated to get my car back to me and out of the hands of the dealer mechanic!

metroplex

When was the fuel filter changed?

The PCM does advance spark when the air and coolant temperature is cold, and reduces this advance until at "operating" temperatures. At higher temperatures, it will retard the timing.

coastalS197

It has done this from day one, I always thought it was something else. Under the assumption, a brand new car wouldn't spark knock. I've paid special attention not to get on it, when its cold. Fuel Filter is on my list of things to change. But since I know the car did it with a brand new fuel filter , w gas of all dif. octane levels. I'm ruling it out, though it is part of my planned maitenance w oil change, air filter, etc. etc. Promptly when I get it back from the dealer.

theedge67

I can't imagine it is spark knock if you are running 93 octane gas with the stock calibration. That just doesn't make sense.

YardSpecial

Well mine pings also, with only 18K miles.

Problem:
Carbon build up

Why:
Wife buys reg octane and sits in traffic. She never beats the car and its a auto.

Fix:

Beat said wife till she learns HOW to drive a mustang safely to stay ping free. (no laws broken) Example: Leave OD off on the freeway on short trips..........

BTW

She killed the 97 GT also till I stepped in and fixed said problem..............

Advice to you:

Buy good gas and run the car at LEAST 40 minutes once a week with no TRAFFIC.

We take our 2 for a cruise to lunch once a week now. Cars/marriage much better now.............

Cobrakev

The Mustang has a 5yr, 60,000 mile power train warranty. IE.. Engine, transmission, rear diff. So the knock sensor, I think should be covered under this warranty.

coastalS197

Thanks everybody for the advice so far. About to call the dealership.

Cobrakev - "So the knock sensor, I think should be covered under this warranty." Knock Sensor could be bad? I am unfamiliar with it.

Yea, I know I have the 5 year 60,000 warranty, I just haven't had time to convince the dealer of it, its a differen't dealer from where I bought the car. I will convince them! Another issue, can you tell I am unhappy with dealer service?

'Yardspecial' your ping was carbon? So you sprayed carb. cleaner in the throttle body? How did you fix it?

Anybody else with pinging problems? and resolutions?

hiznherponies

First, do NOT spray carb. cleaner down the TB!! Throttle bodies are not carbs!! Second, Yardspecial was refering to driving the snot out of it, w/out breaking any laws, like getting on it down your favorite on-ramp, then driving for a while down the highway. I think your problem may be a bit worse, but thats my opinion. Maybe try some "SeaFoam", its an additive you pour in your tank, it'll clean your injectors, i believe.

YardSpecial

Drove the **** out of car with 90+ octane on REGULAR basis. Problem solved for now.

ALL Mustangs PING when driven WRONG............................................. ...........

YardSpecial

hiznherponies

Spot on bro..........

metroplex

FWIW I use 87 octane (cheap grocery gas stuff) in my 07 GT and it does not knock and hasn't since day one. I don't baby the car though so I occasionally open it up, but I do a lot of short (30 min) stop and go driving as well.

Using 93 octane will cause faster carbon buildup since the gas is not burning as completely as 87 octane. Even with an aftermarket tune, 93 octane will still cause faster carbon buildup.

YardSpecial

Using 93 octane will cause faster carbon buildup since the gas is not burning as completely as 87 octane. Even with an aftermarket tune, 93 octane will still cause faster carbon buildup.

Total BS !

The 08 Bullet proves that !!

drive the DAM car, all is good!

metroplex

The 08 Bullitt has a unique system not found on earlier Mustangs, and even so, it will still develop carbon buildup faster than if it used 87 octane. Every Audi, VW, BMW, and Japanese car that required 91 octane (or higher) is proof of this (they can adapt the timing based on what type of gasoline you are using - just like the 08 Bullitt). This is nothing new - Ford just took a very long time to implement it on the Mustang.

Higher octane fuel is not "higher quality" or "cleaner" fuel. It has a higher resistance to detonation and tends to not burn as completely as a lower octane fuel. That is why you want to use 87 octane when going for your emissions inspection (and not 105 octane racing fuel).

hiznherponies

If it was mine, I'd take it to the dealer (or one that you trust!!LOL) and make them fix it, and not accept the car until its fixed to your satisfaction. Make the service manger or mechanic drive it with you, and don't let them BS you about every Mustang makes that sound!!

coastalS197

I know a throttle body isn't a carb, and carb. cleaner & throttle body cleaner are just about the same thing. I don't want to seafoam a 1.5 year old car either.

Update so far: apparently the dealer says there are no TSB's for a misfire, no comp. recalibration's that might reprogram the comp./ adjust air fuel ratio and even the ping out. I'm thinking it could be the one or more of the coil over plugs. Or just a really bad stock tune.

Taking it to the dealer sucks, the only reason I've gotten anything done there is because of my own research.

Anybody got any other idea's? Can't wait to get the stang back!

YardSpecial

It OK , you are STILL wrong !! Pinging comes from oil ingestion, not the fuel grade period DOT. Driving long drives getting the engine to normal operating temps for more then 30 minutes is the key.



My proof:

30 years of running premium gas with NO carbon issues................


Summery

Short distance/traffic and oil ingestion is the problem

Cobrakev

Sorry pinging is Fuel/air ratio....Hence, the reason pinging goes away with higher octane fuels and more advance timing. The 5.0 engines you use to advance the timing until pinging occured, then cut it back 1 or 2 degrees.The later 5.0 engines, and I think All the newer 4.6 engines have a knock sensor. I need to look up to see if these 3V engines have it.

YardSpecial

Pinging is more then AF ratio, carbon also will cause ping.


Come to find out the WIFE was running 87 Octane, so that BLOWs the idea 90+ octane was the cause for carbon build up.

Also we live 100'-1000' above sea level................

lonebear

Have them check the calibration of the MAF.

Also, what oil are you using? Have you considered synthetic?

theedge67

Synthetic oil will not make spark knock go away. It has no effect whatsoever on spark knock.