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Why is my brand new car KNOCKING?

  • Thread starter Thread starter ecko51
  • Start date Start date May 1, 2006
E

ecko51

New Member
May 1, 2005
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May 1, 2006
#1
  • May 1, 2006
  • #1
Man I hope nothing serious is wrong. I just put the frist tank of gas in it on Sunday and now today it sounds like it has a knock at idle, but goes away when it revs up.
I put 89 octane in it because thats what the dealer filled it w/ when I bought it.
Could I have gotten bad gas?
Or is it a sign of something much worse?
I will call them tommorow and get it in.
 

sieben

New Member
Aug 6, 2005
18
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0
May 1, 2006
#2
  • May 1, 2006
  • #2
more info???
 

nycstang37

New Member
Nov 18, 2005
146
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0
Queens, NY
May 1, 2006
#3
  • May 1, 2006
  • #3
are you sure the dealer used 89? b/c the car is supposed to run on 87.
 

JTGrant

New Member
Aug 2, 2005
775
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GA
May 1, 2006
#4
  • May 1, 2006
  • #4
is it a knock or is it fuel injectors?
 
E

ecko51

New Member
May 1, 2005
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May 2, 2006
#5
  • May 2, 2006
  • #5
It's more than just a ticking that the injecters woul make.
 

Szlachcic

New Member
Mar 30, 2005
168
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Raleigh, NC
May 2, 2006
#6
  • May 2, 2006
  • #6
Was your air conditioner on? I believe their is a solenoid or something that makes a ticking or knocking noise every so often when the air conditioner is on. If that is it you get used to it after a while or you can just get a louder exhaust and you won't notice it at all, lol.
 
E

ecko51

New Member
May 1, 2005
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May 2, 2006
#7
  • May 2, 2006
  • #7
Does the defroster use the AC compressor?
If so you may be on to something.
 
S

Spdfreak

New Member
Feb 21, 2006
276
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0
May 2, 2006
#8
  • May 2, 2006
  • #8
Because you won't let it in?

Sorry, I couldn't resist.
 

nycstang37

New Member
Nov 18, 2005
146
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0
Queens, NY
May 2, 2006
#9
  • May 2, 2006
  • #9
Spdfreak said:
Because you won't let it in?

Sorry, I couldn't resist.
Click to expand...


why am i the only one who got that
 

bigcat

start with the upper hole, and if more traction is
May 1, 2005
3,015
1
79
7200 feet
May 2, 2006
#10
  • May 2, 2006
  • #10
ecko51 said:
Does the defroster use the AC compressor?
If so you may be on to something.
Click to expand...
yes, the A/C comes on for the defrost setting.
 

95snoozer

Active Member
Dec 14, 2002
2,572
1
48
RCR
May 3, 2006
#11
  • May 3, 2006
  • #11
i dont care how bad your gas is, there shouldnt be knocking with no load at idle
 
N

NY05GT4ME

New Member
Apr 2, 2005
38
0
0
Upstate NY
May 3, 2006
#12
  • May 3, 2006
  • #12
Spdfreak said:
Because you won't let it in?

Sorry, I couldn't resist.
Click to expand...

Who's there?
 

NK06Roush

New Member
May 3, 2006
24
0
0
Long Island, NY
May 3, 2006
#13
  • May 3, 2006
  • #13
I just bought a week ago a stage 2 roush mustang. The dealer there told me that I can put 87-93 octane in there no problem. He said if you want to put in 93, the computer is tuned to recognize this and you will pick an extra 5 HP. So far I have gone through almost 3 tanks of gas running 93 octane and have no problems.
 

dmaxstang

New Member
Jul 29, 2005
0
0
0
dallas
May 3, 2006
#14
  • May 3, 2006
  • #14
NY05GT4ME said:
Who's there?
Click to expand...

MustangBeats!!!

MustangBeats Who???

Everybody you idiot!!!

Read the manual, it is ok and normal for the car to knock just a bit, but when it becomes abnormally loud you should use your 3/36k warranty. Turn the knob on the right all the way up to the ( 0 ) and see if it knocks still. Then go like hell because the car just got 50% of its power back. HAHA Congrats though on the new ride. Oh yeah, and the raddles that will start in about 4k miles are normal also, have fun.:SNSign:
 
R

Razinhell

New Member
May 29, 2004
62
0
0
May 4, 2006
#15
  • May 4, 2006
  • #15
NK06Roush said:
I just bought a week ago a stage 2 roush mustang. The dealer there told me that I can put 87-93 octane in there no problem. He said if you want to put in 93, the computer is tuned to recognize this and you will pick an extra 5 HP. So far I have gone through almost 3 tanks of gas running 93 octane and have no problems.
Click to expand...
Uh...no. Your car cannot tell what octane the fuel is. What it can tell is that it there is predetonation due to low octane exploding before the spark plug ignites the fuel. In other words higher octance just means it has more chemicals in it to resist the predetonation. You won't gain more horsepower on a higher octance unless your car is already having problems with the lower octance. That is if you have crappy 87 octance gas in your area then your gonna get poor performance. If you move to the next level, such as 89, and there is no more knocking then you are going to get more performance. The only time you will get more performance from a specific octane is if you tune the car to utilize the fuel. Even then unless your running a Forced Induction or other power adders there is no reason for a higher octance unless your area just has poor gas. Now that they are adding ethanol to a lot of fuels there is always a chance that your car won't like the lowest octane. Remember that octane is an average of the Motor and Research method so you may get the low end of the average they may even round up.
 
F

FLY2kGT

Founding Member
Apr 27, 2001
94
0
0
Pinellas Park, FL
May 4, 2006
#16
  • May 4, 2006
  • #16
That comment about the 87 octane gas is great. This thread has now turned into a "get higher octane gas for more performance" thread. Just do a search and some research and you'll find that the ONLY reason to use higher octane fuel is to prevent predetonation. Using 89 or 92 when your vehicle was designed for 87 will NOT INCREASE PERFORMANCE! I've seen this soooo many times over the years and it still baffles me that with today ability to research, people are still confused. I better stop here before I turn this into an essay. Just go research please.
 
C

CPman

New Member
Apr 2, 2005
129
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0
May 4, 2006
#17
  • May 4, 2006
  • #17
It could be a cam phaser noise if the noise goes away above idle. I believe there is a TSB covering that condition. Check it out.
 

JTGrant

New Member
Aug 2, 2005
775
0
0
GA
May 4, 2006
#18
  • May 4, 2006
  • #18
actually some of the new cars (Honda accord) advance the timing until the knock sensors sense knock and the ecu will retard the timing a few degrees. I don't know if our cars do this. I know that we have knock sensors. if you were to put 93 octane or a higher octane fuel than what is in there fromt the factory it will pick up more power if the car had this.
 
E

ecko51

New Member
May 1, 2005
27
0
0
May 5, 2006
#19
  • May 5, 2006
  • #19
Yes it does go away when I get on the pedal even a little.
 
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