At what point will one begin to run lean?

Jsun3701

New Member

Dec 10, 2004

124

0

0

Virginia

Dec 18, 2006

#1

• Dec 18, 2006

• #1

I was talking with a bud today and I told him I heard a noise when I start the Stang in the morning(Like a couple of marbles bangin around). Pretty much just during initial start up or after its sat for a while. He suggested I may be running lean, and hearing some detonation. So at what point and with what mods will one start to run lean, and possibly cause detonation? Or Im I off the rocker.


P.S. I bought the Tri-Ax. and G.D.!!!! what a difference from the stock shifter. Wish I had done it a long time ago.

 

sgarlic

Founding Member

Apr 21, 2001

3,085

1

56

Dec 18, 2006

#2

• Dec 18, 2006

• #2

Well, carbon buildup on the pistons can cause detonation.. you may want to think about Seafoam or something like that.

Some valve noise on cold starts isn't totally uncommon, and Ford said "some is normal" in one of their TSB's. Oil viscosity can affect this too. Too thick of an oil at startup (i.e. 10wX or 20wX) on our engines causes the oil to take longer to reach the top of the engine, therefore causing some valve noise.

If I lived in a place that was cold, I'd run 0w20.

Mod-wise, things that tend to allow for more air to be moved but not have adequate fuel delivery system in place can cause lean conditions. I.e. if you have a blower, or turbo, which moves tons of air, but using stock injectors.. or using a hand-held tuner and leaning it out in the wrong place. If all your mods are listed in your signature, there's not enough to be causing a lean condition.

 

merc123

Active Member

Jan 27, 2003

420

2

39

North GA

Dec 18, 2006

#3

• Dec 18, 2006

• #3

I don't think marbles in a can is detonation. It sounds like your bearings may be going.

 

BurningRubber

10 Year Member

Dec 6, 2004

1,865

24

58

Dec 18, 2006

#4

• Dec 18, 2006

• #4

Detonation shouldnt occure at idle with no load on the engine.

 

03ghoststang

Well-Known Member

Jul 16, 2005

1,930

1

57

Los Angeles, California

Dec 18, 2006

#5

• Dec 18, 2006

• #5

sounds like its something more serious or can it be the head tick that these motors get

 

the98stang

Active Member

Aug 12, 2005

2,408

0

47

Clovis, CA

Dec 19, 2006

#6

• Dec 19, 2006

• #6

Guys, c'mon....we have Fords. This is the problem: Piston slap. VERY common for a lot of Ford/GM cars. The oil isn't completely lubricating the system. I wouldn't worry about it if the noise goes away within one minute. You COULD try a new Motorcraft oil filter with synthetic oil, but I doubt that will help any. Just leave the car alone, it will be fine.

Tanner

 

Jsun3701

New Member

Dec 10, 2004

124

0

0

Virginia

Dec 19, 2006

#7

• Dec 19, 2006

• #7

Thanks for the input guys. Im not too worried the sound only lasts for maybe half a second. I just wanted to have some input from you guys. I run SAE5W-20. Just like the book said with a Mobil filter.I could go lighter with the oil but, not too sure about that. It is castrol I guess I could switch the brand. What flavor do you guys run?

 

Dusstbuster

I love meat more than anything! I just have a spec

May 31, 2004

1,462

33

64

Moorhead, Minnesota

Dec 19, 2006

#8

• Dec 19, 2006

• #8

Mobil1 FTW

 

BurningRubber

10 Year Member

Dec 6, 2004

1,865

24

58

Dec 19, 2006

#9

• Dec 19, 2006

• #9

I use Motorcraft oil and filter. I run 5w30 but they switched the rating to 5w20 in 01 (I think) when they started using the Romeo engines, if I remember correctly.

 

the98stang

Active Member

Aug 12, 2005

2,408

0

47

Clovis, CA

Dec 19, 2006

#10

• Dec 19, 2006

• #10

Jsun3701 said:

Thanks for the input guys. Im not too worried the sound only lasts for maybe half a second. I just wanted to have some input from you guys. I run SAE5W-20. Just like the book said with a Mobil filter.I could go lighter with the oil but, not too sure about that. It is castrol I guess I could switch the brand. What flavor do you guys run?

Click to expand...

You have nothing to worry about. It's knocking for that slight second because there are dry spots in the engine and the oil is trying to work it's way up. Try using a Motorcraft filter and Mobil 1 synthetic oil.

 

P

Pennywise2

Banned

May 16, 2006

1,379

1

0

Dec 19, 2006

#11

• Dec 19, 2006

• #11

If that is really the case than Seafoam your car you will not
be sorry.
I have been useing Mobil 1 and a Motorcraft oil filter since I
got my mustang and I never had one problem.
Mobil 1 is a good quality oil.The shop I work at uses Mobil 1 for
for a reason and Subaru highly recommends it.