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I still can't get rid of my ticking / knocking


bigfoo

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I still have this knocking sound on cold startup, and also after everything is completely warmed up the knocking goes away and there's a ticking, sounds like what a lifter would normally sound like and it's about 1/2 the rpm the engine is turning. I can really only hear it at idle. I've tried the top engine cleaner through the pcv while engine is running.. I've tried using an oil treatment to clear out gook.. I've tried several bottles of fuel injecton cleaner.. I don't get it.. plus, if I rev the engine ( in park) to 5000 rpm (WOT for about 1 second) and let off I get a nice cloud of smoke (not just holding the pedal at 5000 rpm, but at idle mash the pedal to the floor until it hits 5k then let off).

So.. there are no real driveability issues or anything.. just little nuances that I suppose are considered 'normal' by GM.. OH and my 1 quart of oil per 1000 miles thing. But then agaiN i drive hard almost every time I go anywhere so i'm sure that contributes to the oil thing. Maybe the smoke is just oil and I can forget about it. I really don't see any smoke on the highway when I mash it but then again it's hard to see unless it's a lot.

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I have a 98 and I think we have to live with the light knocking at start up, brotha. I tried the wide open throttle suggestion and it still didn't make a difference. I believe you are suppose to do that WOT while moving. I did it on the highway and cleared out all the black smoke. But once it warms up it's quiet as a fan isn't it? I've heard that noise is from carbon build up on the pistons and that the Cadillac dealer can spray some type of cleaner into the spark plug sockets to clear that up.

Also what makes you think it burns a qt of oil per 1000 miles? Do you get a check oil message? When it is a qt low that message will appear according to the manual I believe. Alot of people check the oil dip stick inaccurately. I wait till I get that message then fill it up about a qt. That usually happens mid way thru my oil change. Yeah if you are beating the hell out of it you'll burn oil faster

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I had similar noises on my 93' after awhile. I think the car was driven nicely by the previous owner and was in good condition, but was slowly building up some varnish on the lifters. (105k miles)

I changed the oil; I use Pennzoil 10-30. The sound slowly decreased after a few days of driving. When I next needed oil (1 qt.), about three weeks later I added 1 qt. of Marvel Mystery Oil. Within minutes the noise was almost gone. After a couple of days it was gone.

I know some people think MMO is just "snake oil", but I have proven numerous times in my own vehicles that it can help. It has freed sticky lifters and gummed up carburetors on many of my older cars and worked well on my 93'. It is able to get into tight clearances that may be causing sticky lifters (or other parts) by slowly working through and dissolving the varnish.

It will not fix broken or otherwise damaged parts; i.e., it is not a miracle cure.

If you haven’t tried it yet, give it a try. Add 1 qt to the oil the next time you need oil; allow it some time to do its job.

-George

Drive'em like you own 'em. - ....................04 DTS............................

DTS_Signature.jpg

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I use 10w-30.. I have mobil 1 in there now and I usually like AMSOIL (my favorite) .. I ran out of amsoil so i used mobile 1 and notice more noise than usual (i think).. it's also a lot hotter outside so that could factor it..

I have tried MMO once, i'll try it again.......... Maybe ill try the soak with the TEC through the holes. Oh and scotty, I did get slightly better gas mileage by putting the denso spark plugs in.. went up from about 17 to about 19 city driving. Not bad i'd say, but i doubt the plugs were the only factor as I clean things a lot like the TB and run some sea foam through it occasionally. Haven't tried the in spark plug hole thing yet..

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I know some people think MMO is just "snake oil", but I have proven numerous times in my own vehicles that it can help. It has freed sticky lifters and gummed up carburetors on many of my older cars and worked well on my 93'. It is able to get into tight clearances that may be causing sticky lifters (or other parts) by slowly working through and dissolving the varnish.

It will not fix broken or otherwise damaged parts; i.e., it is not a miracle cure.

If you haven’t tried it yet, give it a try.  Add 1 qt to the oil the next time you need oil; allow it some time to do its job.

-George

Back in the late sixties, I put Marvel Mystery Oil ( along with some scepticism) in an otherwise shot Ford tractor motor. This was with the advise of my grandfather who swore by the stuff (and was in his eighties by then...)

Well, that tired old motor freed up, and started running again, after being darn near froze. It continued to chug along for some years, with frequent oil changes and a good dose of MMO every time. (For all I know, it's still running..)

I still keep a can out in my shop, mainly for the memories. (smells good too..),

But...you never know ;)

'93 STS.. opened, dropped, wide...fast.

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Also what makes you think it burns a qt of oil per 1000 miles? Do you get a check oil message? When it is a qt low that message will appear according to the manual I believe.

The check oil level message comes on just about the time the oil level drops off the dip stick (2 1/2 qts low with 5 qts remaining)

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I still have this knocking sound on cold startup, and also after everything is completely warmed up the knocking goes away and there's a ticking, sounds like what a lifter would normally sound like and it's about 1/2 the rpm the engine is turning. I can really only hear it at idle. I've tried the top engine cleaner through the pcv while engine is running.. I've tried using an oil treatment to clear out gook.. I've tried several bottles of fuel injecton cleaner.. I don't get it.. plus, if I rev the engine ( in park) to 5000 rpm (WOT for about 1 second) and let off I get a nice cloud of smoke (not just holding the pedal at 5000 rpm, but at idle mash the pedal to the floor until it hits 5k then let off).

So.. there are no real driveability issues or anything.. just little nuances that I suppose are considered 'normal' by GM.. OH and my 1 quart of oil per 1000 miles thing. But then agaiN i drive hard almost every time I go anywhere so i'm sure that contributes to the oil thing. Maybe the smoke is just oil and I can forget about it. I really don't see any smoke on the highway when I mash it but then again it's hard to see unless it's a lot.

You are a year early for the piston replacement that we are currently doing on the 2000-2003 models. You probably have excessive carbon. The last ring job that I did, 1996-1999 models, the carbon was so bad that it was obvious the "decarb" that GM recommends does absolutely nothing. 6 of the 8 piston oil control rings were so badly siezed that I had to chip away at them with a screwdriver. Normally, you can just pull them out with your fingernail.

We have a 2004 Deville in the shop for an engine "noise". Stripped the motor down, turns out to have a loose bushing in the small end of one of the connecting rods. Hope this is not a sign of things to come. We also measured the block to piston clearance. Measured out at .004" across the board which is out of spec, so a new motor goes in. A "lot" of the later model Northstar engines seem to be noisy.

Oh well, I can make money doing pistons or rings under warranty, so I guess we'll have at her.

Ian

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I know why bigfoo has this problem. He's too busy fixing that dam (no pun intended) leaky trunk and rust proofing everything instead of driving that caddy of his. I'll bet his next post will be "How did I get flat spots on my tires" LOL I couldn't resist bigfoo. :D

"Burns" rubber

" I've never considered myself to be all that conservative, but it seems the more liberal some people get the more conservative I become. "

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I use 10w-30.. I have mobil 1 in there now and I usually like AMSOIL (my favorite) .. I ran out of amsoil so i used mobile 1 and notice more noise than usual (i think).. it's also a lot hotter outside so that could factor it..

I have tried MMO once, i'll try it again.......... Maybe ill try the soak with the TEC through the holes. Oh and scotty, I did get slightly better gas mileage by putting the denso spark plugs in.. went up from about 17 to about 19 city driving. Not bad i'd say, but i doubt the plugs were the only factor as I clean things a lot like the TB and run some sea foam through it occasionally. Haven't tried the in spark plug hole thing yet..

Good I was hoping you were not using the 5W30 as I would have advised you to use 10W30.. Remember be careful with cleaning your intake/upper engine as you can damage the engine. Do you remember seeing the photos that I think Ian posted where the side of the block was blown out because the engine hydrolocked on sudden acceleration? Those photos were amazing. I will see if I can find them for you. I am quite nervous spraying anything down the TB after seeing that, Mike

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Wow yea.. I'm always careful about that stuff.. Been doing it for years :)

Man this Mobile 1 oil, OMG..

I'm down 2 QUARTS OF OIL IN 1000 MILES with Mobile 1...... The amsoil takes at least 1500-2000 for 2 quarts of oil.. wtf...... that's a tona oil that i'm burning, and it's not leaking out either as far as I can tell (the bottom is clean). Gotta be something I can do..... maybe 10 top engine cleaner decarbs? hehehe

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Wow yea.. I'm always careful about that stuff.. Been doing it for years :)

Man this Mobile 1 oil, OMG..

I'm down 2 QUARTS OF OIL IN 1000 MILES with Mobile 1...... The amsoil takes at least 1500-2000 for 2 quarts of oil.. wtf...... that's a tona oil that i'm burning, and it's not leaking out either as far as I can tell (the bottom is clean). Gotta be something I can do..... maybe 10 top engine cleaner decarbs? hehehe

Yes I was afraid you may have been using Mobil 1 to me its viscosity seems lesser than its spec. When I used it in my 91 4.9 the number 1 bearing knock was much more pronounced. I am sure its great for new engines but I am not a fan of it for older engines, but that's me, I am sure it has lots of fans.

Besides the oil usage, you have smoking, that's consistent with a ring problem. With that cold piston slap, and shutter you describe you may be having a problem in a single cylinder or two. Have you done a compression test? Mike

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What do you guys think of these 'engine flush' things.. or 'engine restorer' and stuff like that.. I've heard some good things and some bad things.. I'll try anything to stop from burning so much oil.. I don't want to mask the problem with something like 'stop smoke and fix oil leak' things.. I want to free the rings or whatever it is..... It can't be too bad because none of my spark plugs are black or wet so it's not horrible but it's enough to be bothersome.. I'm suprised it hasn't tripped an emmissions code :)

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I know why bigfoo has this problem. He's too busy fixing that dam (no pun intended) leaky trunk and rust proofing everything instead of driving that caddy of his. I'll bet his next post will be "How did I get flat spots on my tires" LOL I couldn't resist bigfoo. :D

Thats histerical! FLAT SPOTS!! About a week ago Bigfoo was feeling JUST A SLIGHT shudder (but not all the time).... LOL... Now Pandoras BOX!! :lol::lol:

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Veryyy funny :) I fixed most of my shuddering by taking all the tires off the rims and cleaning them out and balancing them all and rotating and replacing a tie rod end.. that fixed most :) Now if it was only easy to drop the oil pan i'd check out everything in the engine :)

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What do you guys think of these 'engine flush' things.. or 'engine restorer' and stuff like that.. I've heard some good things and some bad things.. I'll try anything to stop from burning so much oil.. I don't want to mask the problem with something like 'stop smoke and fix oil leak' things.. I want to free the rings or whatever it is.....  It can't be too bad because none of my spark plugs are black or wet so it's not horrible but it's enough to be bothersome.. I'm suprised  it hasn't tripped an emmissions code :)

What bothers me about that thought is what IAN said above that he had to use a screwdriver to pry them loose. IAN, how bad was that engine that had the rings stuck, what were the symptoms...

I have a feeling that once the problem begins its too late. The diameter of the piston itself is too small and the skirt/piston rocks causing accelerated wear on the piston and cylinder. I wonder if the cold noise you are hearing is the piston skirt or carbon and why does it stop when the engine is hot? I would do a compression test so I could focus on the specific cylinder.

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What bothers me about that thought is what IAN said above that he had to use a screwdriver to pry them loose.  IAN, how bad was that engine that had the rings stuck, what were the symptoms... 

I have a feeling that once the problem begins its too late. The diameter of the piston itself is too small and the skirt/piston rocks causing accelerated wear on the piston and cylinder.  I wonder if the cold noise you are hearing is the piston skirt or carbon and why does it stop when the engine is hot?  I would do a compression test so I could focus on the specific cylinder.

It was your usual Northstar using oil at an alarming rate. Now I'm not saying that they all do it, but the one's that we have to actually do repairs on are burning oil at something like 1 liter every 1000 kilometers. And when we take them apart, you can see why. There is no oil control going on any longer. By the way, the cylinder walls are "never" worn, so that really isn't an issue. Even on the engines with 100K miles, there is no wear on the cylinder walls. Nothing to speak of on the pistons either. But tons of carbon. I wonder if it might be better to just run premium gas all the time in the engines?

Ian

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Is there anything I can do to fix this without taking it apart? I wish I could just take the bottom end off and pull out the pistons on the rod and fix it but according to FSM you have to replace the bearings or/and the crank or something if you take it apart even once.. what kinda crap is that :) And I'm not sure if the rod caps are bolted.. there was some reason preventing me from doing this.. either not having enough clearance to take the piston out without removing the crank or that i couldn't get the rods out or something I read, i just don't remember now. Must be another way to fix it. Maybe I'll jut run a quart or two of MMO for the next 3-4 oil changes :) Or, maybe I'll try one of those engine flush things.. who knows it could work.. as long as it doesn't do any damage ill try anything

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What bothers me about that thought is what IAN said above that he had to use a screwdriver to pry them loose.  IAN, how bad was that engine that had the rings stuck, what were the symptoms... 

I have a feeling that once the problem begins its too late. The diameter of the piston itself is too small and the skirt/piston rocks causing accelerated wear on the piston and cylinder.  I wonder if the cold noise you are hearing is the piston skirt or carbon and why does it stop when the engine is hot?  I would do a compression test so I could focus on the specific cylinder.

It was your usual Northstar using oil at an alarming rate. Now I'm not saying that they all do it, but the one's that we have to actually do repairs on are burning oil at something like 1 liter every 1000 kilometers. And when we take them apart, you can see why. There is no oil control going on any longer. By the way, the cylinder walls are "never" worn, so that really isn't an issue. Even on the engines with 100K miles, there is no wear on the cylinder walls. Nothing to speak of on the pistons either. But tons of carbon. I wonder if it might be better to just run premium gas all the time in the engines?

Ian

What is the procedure for taking it aparT?

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I would not go with the flush , you never know what might be dislodged and where it might show up next. I have used MMO for over thirty years and have soaked lifters in it out of the car and completely dislodged them , where you could not push the plunger down no matter how hard i tried on the bench. I do not know what is in it , but it has worked many times for me over the years. I Put A quart in every other oil change , and mine is as quiet as a mouse peeing on cotton.

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Heh.. well i'll hit up MMO in every oil change until it stops then. Worth a shot.. Unless it just burns off all the MMO in the first 100 miles lol!

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bigfoo,

sounds like it is carbon build up. I had this problem as well with my 98 deville. It seem to be more defined as I accelarated up hills. I have a good friend at the dealership that advised me to purchase a can of BG44K. I added the whole can to about a 1/2 a tank of gas. Then on my next fill up I ran pure gas. Then on my 2nd fill up I added another can. It seemed to work fine as my "labor knocking" sound went away. That stuff runs about $20 dollars a can. If carbon build up is

really bad then the dealer will clean it for about $175.00 I believe. Good luck.

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What is the procedure for taking it aparT?

Are you asking about taking the engine apart? If so, you cannot do this with the engine in the car. You could get the heads off in the car, but you cannot get the bottom end apart while the engine and trans are still in the car. So basically, the

engine has to come out before you can get the bottom end apart. Big job.

Ian

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