Engine knocking.. Help please !!!!!!

[rcapilli]

I have a 2001 Cobra with 46,000mi on it. There are no mods to the car. I noticed a knocking noice the other day and narrowed it down to some details. This behavior is a little different than some I have read, so read with a keen eye please.

Then I first start my engine it is great. No knocking at all. After about 3 minutes of driving I can hear a faint knocking. 10 minutes of driving I can really hear it. When I pop the hood and rev the engine I can hear the knocking from the back of the motor near the firewall. While driving you hear the knocking when you let up off the pedal just a little bit as though to give it gas but you are not really putting much power into the car. I took it to the dealership and they did a oil flush. They said some sludge came out of the car but the knocking still remained. Cylinders 1 and 6 are said to be having the problem. The dealerships solution was a new engine. I don't think I am sold on that suggestion quite yet. I am looking for some suggestions and wondering if some of the weird products like Z-Max or anything like that would help. What could this be and am I doomed here? I really don't want to refinance my house for $7,000 worth of a new car engine. Ya know?

Lastly... if I HAVE to spend $7000 for a new engine what should I get? I need one that is already built, buy and put in. Might as well go for something Bad Ass, right?

 

[Kilgore Trout]

A new engine? That seems a little extreme... I would take it to another dealership and get it diagnosed for real.

 

[Dan_Soprano]

A new engine? That seems a little extreme... I would take it to another dealership and get it diagnosed for real.

 

[rcapilli]

I agree, That is what I am going to do. May be a 3rd oppinion also. Any other ideas/suggestions?

 

[Kilgore Trout]

Well, I do not know much about the problem you are describing. It could be a number of things. I believe that there is a TSB about Cobra heads "ticking" and a cold start rattle from the engine. You might try using SeaFoam on it, but that is just grasping at straws really...

How well has the car been maintained? Has it had regular oil changes and such?

 

[CanadaStang]

It's pretty tough to diagnose without actually being able to hear it, but I'm with the others on taking it somewhere else.

 

[CanadaStang]

A few times now I've had customers complain of a knocking noise and I've found a piece of the tin foil from an oil container sticking on top of the lifter.

 

[tomustang]

spun a bearing.

 

[tomustang]

stop driving the car or you'll lose your whole engine

 

[deftsound]

stop driving the car or you'll lose your whole engine

damn tom your a bad ass

 

[Gearbanger 101]

spun a bearing.

Ahhhhh memories, huh Tom?

 

[Mike97gt]

if he spun a bearing it he needs a rebuild anyways.. but what he is describing could be a lot of other things too.. first check your plugs... loose plugs where the threads start too strip out can cause a ticking when the engine warms up.. if thats the case remove the plugs.. put some anti seize on them and tourqe them down and recheck every few thousand miles.. without hearing the noise it is impossible too tell whats going on..

BTW there was sludge in the motor? how often do you change your oil.. change your oil often in any performance application.. the more the better.. i dont care what these 20k oil change people on here say.. when you go long without oil changes you get sludge and bearing wear..

hopefully it's just plugs loose or somthing other than a bearing.. if it is i would either build up somthing good or try too get a used motor.. stay away from the ford dealer RMP crap.. those motors suck..

 

[hotmustang331]

Well, it is possable that your knock sensor went out...and your building carbon. that may be causing detonation. How often is the car nailed? If its just putted around, that may be it. Try some seafoam first, along with checking your plugs. And I WOULD NOT put lock tight on the threads since the heads are aluminum...if anything, we put antiseize. If you do, I doubt you will ever get them back out....especially the red stuff lol.

 

[Kilgore Trout]

And I WOULD NOT put lock tight on the threads since the heads are aluminum...if anything, we put antiseize. If you do, I doubt you will ever get them back out....especially the red stuff lol.

No one said ANYTHING about putting lock tite on anything except you

 

[hotmustang331]

Opps...missread above post. thought he said "locktight" for some reason...hmm

And dont get smart Mr K&N filter boy. LOL

 

[Kilgore Trout]

Well, it is an important point because there was a rather heated debate on the subject of lock tite on plug threads... It is not recommended

Ford's fix for spark plug blowout is using AGSF series plugs instead of AWSF series.

Also, checking the plug torque a while after installing new plugs will help prevent spark plug blowout.

 

[FalconGuy016]

MMmmm, $7000 ...

http://modularpowerhouse.com/produc...id=54&osCsid=2b42c1dbb74af0034f94fbdca1c69872
+
http://www.kennebell.net/superchargers/ford/gt96-03_2v/gt96-04.htm

Sure it's 2v but... a badass one.

 

[Red2000GT]

Mechanical damage dosn't come and go depending on the temperature of the motor. I'd check 2 real easy things(things I can talk about from personal experience). 1)Check to see if something is hitting the hood of the car when running. My upper intake hits very slightly on my hood from time to time and from inside the car it sounded exactly like a bad bearing.
2) check everything around the lower half of the motor. If a motor mount has worn out the exhaust may hit on the steering shaft and cause a very similar noise,but the main thing is to look for anything that could be hitting between the engine and the car itself.

I'm not saying that it's definately not a spun bearing but always check the easy stuff first before getting too excited.

 

[Mike97gt]

Well, it is an important point because there was a rather heated debate on the subject of lock tite on plug threads... It is not recommended

Ford's fix for spark plug blowout is using AGSF series plugs instead of AWSF series.

Also, checking the plug torque a while after installing new plugs will help prevent spark plug blowout.

a long time ago ford had us locktite some lighting plugs before they came out with the "fixed" plug.. well anyways i dont want too start that debate again..

you could put locktite on them.. and if you did they will never loosen up again.. BUT i tried this and noticed when i got them out the threads were a little damaged and needed too be chased too get another plug back in.. so instead i would use antiseize tourqe them down right and recheck often.. this was done on a 5.4 supercharged truck

we tried this on a couple of different 5.4 supercharged trucks.. and in a extreme situation i would still use this.. ( heavy boost, idiot owner that would never check the plugs) but for your average mustang just check them every so often..


back in that debate there was a few people that said the locktite would cause them too back out and that is just retarded... the use of a medium strenth high heat locktite would not cause that..

 

[Mike97gt]

Opps...missread above post. thought he said "locktight" for some reason...hmm

And dont get smart Mr K&N filter boy. LOL

lets not rehash a 6 month old heated debate... the locktite thing is dead leave it dead.. we did use it on a few trucks and we got the plugs out.. had too chase the holes too get plugs back in LOL but i got them out.. agian

I DO NOT RECOMEND THE USE OF LOCKTITE BY ANY MEMBER OF THIS BOARD.. but i still will continue too play with it and test it on my own.. if i ruin a cylinder head it's not the end of the world for me..

i have never had a locktite plug loosen up.. but i have seen thread damage from it..

so for you guys i recomend..

1. antiseize and proper tourqe and retighten as they loosen (if they do)

2. or just put them in the way ford does.. with no crap on them at all.. works fine and i have gotten them out with 150k plus miles on them..

we have more problems with iron head fords seizing the plugs... never had a problem with a aluminum head ford and a plug seizing.. the old 5.8 is known too have the plugs seize too the head.. and that a iron head..


maybe in the early days of aluminum heads there was seizing problems due too two different metals reacting over time.. but this has LONG been worked out..