98 Sable Engine Noise

Chris Hill · 01-23-2011, 07:37 PM

If you would, please view the youtube video listed below.

This is the same 98 Sable with DOHC Duratec engine I was asking about last week. The issue last week was the fuel pump and the fuel pump check valve just after the pump were both bad. I put in a new pump and module yesterday and it now runs after 18 months sitting.

It runs now, but makes a bad ticking/knocking noise and I think it is comming from the front valve cover area. It definitley is dependent on engine rpm. I pulled the front valve cover looking for a down lifter or lash in the valve train or something obvious, but everything seemed to be ok.

I am not a mechanic by any means and I'm trying to help out a friend here, but I don't know what is causing the noise. If you could, please view and listen to the video and give me your ideas on what is wrong and how serious it is.

Thank you,

Chris

Chris Hill · 01-24-2011, 10:44 AM

I'm still trying to figure this one out.

Would piston slap occur once per engine revolution, twice per revolution, or every other revolution when the engine fires.

Also, if a rod bearing is going down, would it happen once per engine revolution, twice per revolution, or every other revolution when the engine fires.

Thank you,

Chris

StripeHOG · 01-25-2011, 02:42 PM

timing chain slop?? possible from sitting a tensioner may have stuck??

NORVELL BOWERS · 01-30-2011, 11:36 AM

Chris, most of the time when i have heard that sound it was a piston. It sounds like on top of the head but is normaly a piston. To tell try killing 1 cylinder at a time and see if the noise greatly decreases when you pull the noisy culprit.If it is a piston it should almost get rid of the knock when you kill the corresponding cylinder Good luck.

Greg Reimer 7376 · 01-30-2011, 11:59 AM

Sounds like an object on a piston. A spun rod bearing could do that, because the increased bearing clearance allows the piston to travel up the cylinder on the exhaust stroke striking the head. That's a pretty obnoxious clatter, but the engine seems to run on all six cylinders. If a screw or washer or even a big piece of carbon landed on the piston and partially embedded itself, that would do it, too. Good luck!!

BillK · 01-30-2011, 01:01 PM

Chris,

There is a service bulletin having to do with a "ticking" noise when hot but I really think that the noise you have is much more than what they are describing in the bulletin. I have to agreee with the others that it sounds like a rod bearing, maybe wrist pin, etc. Definitely sounds piston related rather than valve train.

I checked on another automotive site that I have access to and found a lot of valve train noise issues but only one with a knock that "sounded" like yours. This one had a piston hitting the crankshaft counterweight, probably due to a hydrolock slightly bending the rod. If you can isolate it to one cylinder, maybe see if you can look down through the spark plug holes and see if it is cleaner than the rest ? A borescope would be nice. If it had a leaking head gasket and got water into the cylinder this would be a possibility. How was it running prior to the fuel pump issue ?

01-23-2011, 07:37 PM	#1
Chris Hill Senior Member Join Date: Jan 2002 Posts: 654 Likes: 8 Liked 244 Times in 26 Posts	98 Sable Engine Noise If you would, please view the youtube video listed below. This is the same 98 Sable with DOHC Duratec engine I was asking about last week. The issue last week was the fuel pump and the fuel pump check valve just after the pump were both bad. I put in a new pump and module yesterday and it now runs after 18 months sitting. It runs now, but makes a bad ticking/knocking noise and I think it is comming from the front valve cover area. It definitley is dependent on engine rpm. I pulled the front valve cover looking for a down lifter or lash in the valve train or something obvious, but everything seemed to be ok. I am not a mechanic by any means and I'm trying to help out a friend here, but I don't know what is causing the noise. If you could, please view and listen to the video and give me your ideas on what is wrong and how serious it is. Thank you, Chris __________________ Chris Hill https://ihmusedparts.com

01-24-2011, 10:44 AM	#2
Chris Hill Senior Member Join Date: Jan 2002 Posts: 654 Likes: 8 Liked 244 Times in 26 Posts	Re: 98 Sable Engine Noise I'm still trying to figure this one out. Would piston slap occur once per engine revolution, twice per revolution, or every other revolution when the engine fires. Also, if a rod bearing is going down, would it happen once per engine revolution, twice per revolution, or every other revolution when the engine fires. Thank you, Chris __________________ Chris Hill https://ihmusedparts.com

01-25-2011, 02:42 PM	#3
StripeHOG Junior Member Join Date: Jul 2006 Location: Greentown,IN Posts: 9 Likes: 0 Liked 0 Times in 0 Posts	Re: 98 Sable Engine Noise timing chain slop?? possible from sitting a tensioner may have stuck??

01-30-2011, 11:36 AM	#4
NORVELL BOWERS Junior Member Join Date: Oct 2009 Location: Sulphur Springs Posts: 76 Likes: 0 Liked 1 Time in 1 Post	Re: 98 Sable Engine Noise Chris, most of the time when i have heard that sound it was a piston. It sounds like on top of the head but is normaly a piston. To tell try killing 1 cylinder at a time and see if the noise greatly decreases when you pull the noisy culprit.If it is a piston it should almost get rid of the knock when you kill the corresponding cylinder Good luck. Last edited by NORVELL BOWERS; 01-30-2011 at 11:39 AM.

01-30-2011, 11:59 AM	#5
Greg Reimer 7376 VIP Member Join Date: Nov 2008 Location: Glendora,Calif. Posts: 1,130 Likes: 172 Liked 698 Times in 216 Posts	Re: 98 Sable Engine Noise Sounds like an object on a piston. A spun rod bearing could do that, because the increased bearing clearance allows the piston to travel up the cylinder on the exhaust stroke striking the head. That's a pretty obnoxious clatter, but the engine seems to run on all six cylinders. If a screw or washer or even a big piece of carbon landed on the piston and partially embedded itself, that would do it, too. Good luck!!

01-30-2011, 01:01 PM	#6
BillK Member Join Date: Nov 2005 Location: Waldorf Md Posts: 230 Likes: 12 Liked 30 Times in 17 Posts	Re: 98 Sable Engine Noise Chris, There is a service bulletin having to do with a "ticking" noise when hot but I really think that the noise you have is much more than what they are describing in the bulletin. I have to agreee with the others that it sounds like a rod bearing, maybe wrist pin, etc. Definitely sounds piston related rather than valve train. I checked on another automotive site that I have access to and found a lot of valve train noise issues but only one with a knock that "sounded" like yours. This one had a piston hitting the crankshaft counterweight, probably due to a hydrolock slightly bending the rod. If you can isolate it to one cylinder, maybe see if you can look down through the spark plug holes and see if it is cleaner than the rest ? A borescope would be nice. If it had a leaking head gasket and got water into the cylinder this would be a possibility. How was it running prior to the fuel pump issue ? __________________ Bill Koustenis