2006 Baja Turbo Engine Knock when Cold

Technical Discussions - Got a mechanical problem?

Moderator: bajabob

Post Reply
RickBaja06
Scoobytruck Contributer
Posts: 58
Joined: Tue Sep 04, 2007 4:18 pm
Location: Massachusetts

2006 Baja Turbo Engine Knock when Cold

Post by RickBaja06 »

I have read about engine noise when 1st starting a cold engine. But my engine is making a very loud knocking sound when 1st started after being left off for over 8hrs. Once the engine is warm the knock starts to go away. The knocking sound goes away completely after about 5 minutes. I do not have issues with lack of poor or a really rough idle. I use 93 Octane and have used fuel system cleaner.

Is this really normal for the 2.5L?

The car has 21K miles, Oil level is fine and oil is fresh.

Thanks
Rick
Hawk296
Scoobytruck Master
Posts: 295
Joined: Thu Mar 31, 2005 5:21 pm
Location: Waterford, MI

Post by Hawk296 »

piston slap......
RickBaja06
Scoobytruck Contributer
Posts: 58
Joined: Tue Sep 04, 2007 4:18 pm
Location: Massachusetts

Post by RickBaja06 »

Thanks for the info, my engine must be slap happy because you can hear it inside the cab.
Hawk296
Scoobytruck Master
Posts: 295
Joined: Thu Mar 31, 2005 5:21 pm
Location: Waterford, MI

Post by Hawk296 »

Yeah, it sounds like the classic piston slap. The dealer will tell you its normal. Its a design flaw, some do it worse than others. Its the byproduct of having a short piston skirt. The older skirtless pistons were even worse. As the parts heat up and expand, the noise will go away.
RickBaja06
Scoobytruck Contributer
Posts: 58
Joined: Tue Sep 04, 2007 4:18 pm
Location: Massachusetts

Post by RickBaja06 »

I thought my car suffers from piston slap but I actually think it is coming from an either an electrical component or an injector. Reason for that assumption comes from the fact that I can trigger the knocking sound by turning the ignition on and a growling sound is heard which is not a normal everyday sound. When you hear that sound and start the engine you get the knocking, if you do not hear that growling sound the knocking it not present. Since I can trigger the sound it seams to be more electro-mechanical than just purly piston slap. I have no check engine lights or crazy engine vibrations or hesitation. I am going to try some fuel injector cleaner and see if the problem goes away.
bulwnkl
Scoobytruck Master
Posts: 229
Joined: Sun Jun 17, 2007 8:37 am
Location: Arizona, USA

Post by bulwnkl »

Is there any possibility of a fuel pump issue?
User avatar
davecoon13
Scoobytruck Master
Posts: 249
Joined: Sun Aug 06, 2006 10:56 am
Location: Alexandria, VA
Contact:

Post by davecoon13 »

My 2003 Baja Sport had a knock and a really rough idle. I put 3 cans of Berryman's Chemtool B-12 in the gas and it seems to have solved the issue. I must have just had carbon buildup or something.
Dave Coon
www.nflcrimes.com
SilverStone Metallic
2003 Baja Sport 4EAT
"Capped" with A.R.E. Topper
RickBaja06
Scoobytruck Contributer
Posts: 58
Joined: Tue Sep 04, 2007 4:18 pm
Location: Massachusetts

Engine knock resolved

Post by RickBaja06 »

The engine knock was being produced by the timing belt tensioner. The noise only happened when the temperture dropped below 60F after the engine was warm the noise would go away.
mbaksic
Scoobytruck God
Posts: 559
Joined: Mon Dec 27, 2004 11:23 pm
Location: Mukwonago, Wisconsin

Post by mbaksic »

Thats good to know. So when I replace the timing belt, I will change out the tensioner. I planned on doing that anyways, along with the waterpump.
Mike
Even though I work on Dodges, I don't own one.
Post Reply