Knocking at startup, only at startup

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rwurst918

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I am having this problem that I know now is not the tensioners because this knocking is not constant. When I start my LS V8 I am having a knocking noise for approximately two seconds then it stops. This does not happen every time I start my LS. It only happens after the car has been sitting for about four hours. Even after a cold startup I have turned off the LS then restarted it to find that there is no knocking on that restart. It seems like it is having an oil drain problem somewhere. I have researched this on here and I found that I have to use better than fram oil filters. I just put a Wix on it that does have the anti-drainback valve (15 bucks). It did help a little bit by making the noise not nearly as loud, but it is still there for the two seconds, once again only on startup. Upon an immediate restart, it does not have the knocking. I have been using 5w30 full synthetic Mobil One. I read somewhere on here that if I am going to use full synthetic I would have to switch to 0w30. Is this true? I also have read on here that my idler pulley is possibly bad. How can I check to see if it is? I do know everything is tight on the serpentine system. When I bought the car I did notice that it has a small oil leak on the oil pan that had a jb weld rigged fix on it. I do not know what damage had been done to the oil pan, but it seems as if its shape is normal. That fix is now failing and causing a very slow oil leak from the oil pan. Is there some crazy way possible this could be the problem or maybe something in the oil pan that needs changed?
 
There is some debate here about which oil is best. Ford recommends 5W20 (required on gen II, just recommended on gen I). 0W20 is even better. Try 0W20 on your next oil change and see if that helps with the tapping/knocking. If the sound is coming from the valve cover area, then it may be that you need to adjust the valves. Adjustment is made by adding shims.

All in all, unless it is a loud knocking and not a slight tapping, it's not anything to worry about.
 
oil leak

I've been using fram filters on my 01 since new,,,,,,,no problems whatsoever.
If you have an oil leak, then your oil pressure will be low, does your oil light indicate low pressure? I would think that this is your problem with the knocking on startup as you are not getting adequate oil pressure. check your oil sensor for leaks too. Seal those leaks. You may also have a failing oil pump. Not heard of many pumps failing on these cars.
 
There are no lights on at all in my car. ran scantool and nothing also.
 
I would say that the oil is not getting to valve assembly right away or leaking back down like you said. When you do a change on one of the f-150's with the three valve 5.4 and then refill it and start it up it sounds like a damn deisel until the oil gets up to the valve train. Could it be poosible that oil is leaking down through the valves into the cylinders? I dont know how they seal these cars around the valves or maybe the valve cover gasket is bad. Have you noticed it burning oil or the level is down any? You could try an oil stabalizer like lucus, its thick as honey and might help with the valves i know it helped with my old car with that tapping sound you're hearing.
 
2002_lincolnLS said:
I would say that the oil is not getting to valve assembly right away or leaking back down like you said. When you do a change on one of the f-150's with the three valve 5.4 and then refill it and start it up it sounds like a damn deisel until the oil gets up to the valve train. Could it be poosible that oil is leaking down through the valves into the cylinders? I dont know how they seal these cars around the valves or maybe the valve cover gasket is bad. Have you noticed it burning oil or the level is down any? You could try an oil stabalizer like lucus, its thick as honey and might help with the valves i know it helped with my old car with that tapping sound you're hearing.
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Mine does sound like a diesel on startup. It is not burning any oil. the level does not drop at all. i will try oil stabilizer tomorrow. thanks
 
im sure yours doesnt sound like a deisel its just those 3 valve 5.4 motors that do that when they are dry, but its the same concept. the lucus should help out alot.
 
Lincoln Jealous said:
coils/plugs
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What makes you think its the coils/ plugs? I have no lights on the dash, it starts right up, and it runs great except for that startup knock. I also have just put in the lucas oil stabilizer and it didnt help. It also didnt make it worse. I ordered a new oil pan. Im gonna see if there was further damage done to what is underneath the oil pan when I replace it. Does anyone know an approximate cost to adjust the valves cuz it seems like thats what Im going to have to do? This sucks because last week I found out that I have a bad front hub. I just ordered it today from detroit axle. Im gonna be pissed if its gonna be a pain in my arse to change. I looked at the hub and the aluminum and it seemed as if it did not bond together yet. I will see here in the next few days if it did.
 
rwurst918 said:
What makes you think its the coils/ plugs? I have no lights on the dash, it starts right up, and it runs great except for that startup knock. I also have just put in the lucas oil stabilizer and it didnt help. It also didnt make it worse. I ordered a new oil pan. Im gonna see if there was further damage done to what is underneath the oil pan when I replace it. Does anyone know an approximate cost to adjust the valves cuz it seems like thats what Im going to have to do? This sucks because last week I found out that I have a bad front hub. I just ordered it today from detroit axle. Im gonna be pissed if its gonna be a pain in my arse to change. I looked at the hub and the aluminum and it seemed as if it did not bond together yet. I will see here in the next few days if it did.
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Lincoln Jealous seems to like to post quick, often incorrect, solutions.

I don't like oil, transmission, or other additives, and I wouldn't ever use them.

I don't know the cost to adjust the valves, but there is a good bit a precise labor involved, so it's not going to be cheap. You need to find someone who's done it before. It can be annoying to have some tapping, but if he goes too far the other way, you will burn your valves out before long.

I'd use a stethoscope to make sure the noise is from the valve train. It might be something worse if that hole in the oil pan means that someone ran it with very low oil for a while. I'd say take the pan off and see what's going on in there before doing anything else.
 
rwurst918 said:
Im gonna be pissed if its gonna be a pain in my arse to change. I looked at the hub and the aluminum and it seemed as if it did not bond together yet. I will see here in the next few days if it did.
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It's pretty easy to change.. I did both fronts in like an hour..
 
FASTLLS said:
It's pretty easy to change.. I did both fronts in like an hour..
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As long as they haven't made sweet, sweet love. It's too common for the hub and spindle to get bonded together.
There is another thread recently where someone had to use bolts through the hub to push it off.
 
+1 joegr

I agree with Joegr, one step at a time. Rarely hear of anyone needing to adjust valves. Doubt if that is the problem. Fix the leaks first. Valve cover gaskets, oil pan gaskets, oil sensor, etc. before anything else.
 
joegr said:
Lincoln Jealous seems to like to post quick, often incorrect, solutions.

I don't like oil, transmission, or other additives, and I wouldn't ever use them.

I don't know the cost to adjust the valves, but there is a good bit a precise labor involved, so it's not going to be cheap. You need to find someone who's done it before. It can be annoying to have some tapping, but if he goes too far the other way, you will burn your valves out before long.

I'd use a stethoscope to make sure the noise is from the valve train. It might be something worse if that hole in the oil pan means that someone ran it with very low oil for a while. I'd say take the pan off and see what's going on in there before doing anything else.
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and joegr seems to work at home
 
I just changed the oil pan out and found out the old one had seen some damage near the plug drain. It looks like they welded the damage to the pan to make it close again. It also looks like they had put some type of resin on the inside of the pan to make it not leak also. I found their was black rtv silicone near the damage to hide the dents and welds that were on the pan. Who the hell would do this. Anyways, I have traced the sound of the knocking to near the intake. Could this mean an intake gasket going bad? While listening after the startup knocking, I hear faint knocking coming from the intake area until the car warms up. I just changed out the passenger side front hub. Very easy. It isn't the problem though. Im not getting a whining noise but I am getting an almost grinding noise when going faster than 15mph and it stops after about 45mph. You notice it is rotational when you hear it at a certain point and then it grinds and goes around then grinds again. Could tires do this? Balance is good up to about 130 mph (I was pissed and wanted to know if it was a simple balance problem. Yes I know very stupid). I am thinking about changing out the driver's side front hub. I have changed out all the pads and rotors so I know they cant be it. What else can go bad? Wait I have an LS. Something else will go wrong tomorrow.
 
rwurst918 said:
I just changed the oil pan out and found out the old one had seen some damage near the plug drain. It looks like they welded the damage to the pan to make it close again. It also looks like they had put some type of resin on the inside of the pan to make it not leak also. I found their was black rtv silicone near the damage to hide the dents and welds that were on the pan. Who the hell would do this. Anyways, I have traced the sound of the knocking to near the intake. Could this mean an intake gasket going bad? While listening after the startup knocking, I hear faint knocking coming from the intake area until the car warms up. I just changed out the passenger side front hub. Very easy. It isn't the problem though. Im not getting a whining noise but I am getting an almost grinding noise when going faster than 15mph and it stops after about 45mph. You notice it is rotational when you hear it at a certain point and then it grinds and goes around then grinds again. Could tires do this? Balance is good up to about 130 mph (I was pissed and wanted to know if it was a simple balance problem. Yes I know very stupid). I am thinking about changing out the driver's side front hub. I have changed out all the pads and rotors so I know they cant be it. What else can go bad? Wait I have an LS. Something else will go wrong tomorrow.
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metal grinding that comes and goes could be the ac compressor
 
AC compressor works perfectly and the rotational sound is only when I am driving.
 
Hearing the knocking on the intake could be a sticky or collapsed lifter or cam follower. Try a little lucas oil or even Marvel mystery oil. It will clean out the oil galleys and remove deposits that may be clogging the lifter/follower. Im not seeing a coil/plug issue, Im also not seeing a intake manifold leak. You would have a surging/rough idle if that was the case. Try a little additive in the oil and see how that works. Thats the cheapest and quickest resolve. Also carbon buildup in the cylinders with cause a little spark knock at startup. Im not sure of your mileage of the car. Maybe a seafoam treatment may also help you out.
 
BlackenedMark8 said:
Hearing the knocking on the intake could be a sticky or collapsed lifter or cam follower. Try a little lucas oil or even Marvel mystery oil. It will clean out the oil galleys and remove deposits that may be clogging the lifter/follower. Im not seeing a coil/plug issue, Im also not seeing a intake manifold leak. You would have a surging/rough idle if that was the case. Try a little additive in the oil and see how that works. Thats the cheapest and quickest resolve. Also carbon buildup in the cylinders with cause a little spark knock at startup. Im not sure of your mileage of the car. Maybe a seafoam treatment may also help you out.
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Bad suggestion. The LS engines do not have hydraulic lifters.
 
one thing at a time

all this stuff at once, slow down, one thing at a time. Seems like everything is connected to the leg bone, then the shin bone, etc, etc. Let's fix one at a time, then move on to the next. The LS will have another one coming any time, but with patience, it will run great. grinding could be wheel bearings, or warped rotor, or brake problem. never heard of tires grind, they usually thump, or are just noisy because of the tread design.
 
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