Engine Tapping/Clicking Noise at Start up (1 Viewer)

[campoj2]

The big thing that I discovered about this problem is that it could one of two issues, either a semi-simple exhaust leak, or the piston slap, for which there is no real solution (I think) other than having someone rip into your motor and make an adjustment. I initially thought that it is was a bad/collapsed lifter, and that would be a fairly easy problem to fix, but it would require someone to dive into your motor and make the repair, and you never really know the true competency level of the mechanic doing the work. Some are excellent and some are not.

 

[Topoguide]

No fix for the piston slap short of tearing into the motor as campo stated. Dclee yours is an 04 so you have the new manifold that does not leak (typically)...

If it is a lifter it would not be too hard to fix, but the piston slap is much more difficult. If it is determined to be piston slap it is OK to leave it be. There are other opinions about this, but Toyotas official story is that is a normal behavior on some vehicles. Also many other manufacturers have this issue now, as noted previously Subies do it too.

From my research here is the story on the piston slap: The problem is the piston design has a shorter skirt to save weight to produce more power this requires a slighltly offset positioning of the connecting rod to the piston to keep it from slapping. For Toyota some of these parts are at the edge of tolerence so when the engine is cold that piston slaps until it heats up enough for the metal to expand and have a better fit. Any extra wear should be very limited (but possible) and won't be noticed until a lot of miles are put on the truck, not that I have studied or seen studies on any possible extra wear if there is any.

That said you can do a couple things. Run a lighter weight oil in winter, run synthetic oil, keep it in the garage, add a block heater, and if you don't like any of those come join me in Phoenix where the days you have the sound are very limited. Of course you can always take it to Toyota and see what the will do for you, if you do please post back and let us know what happens.

 

[campoj2]

And that's that...Excellent sumation!

I will take a look into this next week and see what I can find or should I say what the dealership has to say. If it's the exhaust manifold, then it will be repaired, if it's the piston slap, I will leave the sleeping dog alone and move to Phoenix

 

[9toys]

Both my 99LC and '04 Tundra as well as my previous '00 Tundra have had the momentary piston slap or valve clatter, or whatever it is, on cold mornings since they were new. I've just learned to ignore it. If any of them were going to self destruct, they would have by now.

 

[campoj2]

Harker Heights? Lived there for a few years...507th Medical Company (Air Amb)

 

[Gabby]

Our 2000 has had a "tick" upon cold start almost since new. Prolly a cracked exhaust manifold on the driver's side. The dealer said it was nothing when we asked them about it when it was still under warranty--go figure

It quiets down when the manifold heats up enough to seal up the crack. One day I may get around to taking the manifold off. If it is cracked at the flange, where I think it is, I will have it welded, and maybe ceramic coated inside and out. As I understand things, the coating will lessen the thermal expansion and contraction that cracks the stainess tubing. Also, a used manifold has been "annealed" by the many heat/cool cycles, and the metal may be tougher than a new one--such that a welded repair may last as long as the truck.

I too, look forward to someone designing a cost effective set of tube headers that will drop in and bolt up to the exhaust.

 

[dclee]

Thanks for the info guys! I do notice it seems to happen only when cold, or a cold start (even though we keep the truck garaged). It doesn't sound like an exhaust leak. Never noticed it from new off the dealer lot up until just a few weeks ago. I'll try a lighter weight oil.

 

[campoj2]

After driving close to 1000 miles today I can safely say that this is an exhaust leak. Now I just have to find it.

 

[2000UZJ]

What could you use to to weld it up? Untill we find a solid source of headers.

My dealer said they could pull both for 50$ of the clock. Then I will get them welded. Good idea?

 

[freeheel720]

I welded my driver's side exhaust manifold about 12 months ago. It was cracked at the flange and a simple weld on the inside seems to have done the trick. I welded it with a flux core wire with shielding gas, but just because that's what I had. The manifold itself is fabricated, not cast, so it should take the weld easily. Also, the FSM spec for flatness on the manifold-head mating surface is not very tight, so I just ground it by hand until I thought it was flat enough. It hasn't leaked for a year. However the passenger side has started leaking. I'll fix that one when the wife complains enough.

I now have both the piston slap and a manifold leak. The manifold leak is a light ticking sound. What I believe is the piston slap makes my 100 sound like a diesel for a minute or two.

Good luck.

 

[campoj2]

I now have both the piston slap and a manifold leak. The manifold leak is a light ticking sound. What I believe is the piston slap makes my 100 sound like a diesel for a minute or two.

Good luck.

When the noise was still there after a nice 14 hour ride I knew what I had could not be a piston slap, I am hoping I don't have a combo deal like you have, piston slap with an exhaust leak sounds like it could get a little noisy on a cold morning.

 

[5Cruiser]

Okay, I know this is an old thread, and there's now DT headers available through group buys. But...

I'd like to know more about the ticking. I've got a 99. It makes all kinds of noises. I'm not sure if what I am hearing is what you guys are talking about. More details?

Is there any negative affect of this other than noise?

I've got to get sliders and a belly pan before headers, but with the group buy method being the only way to get them, I don't want to miss out on the next one...never know when there won't be a next.

 

[PhrogsPhorever]

The 2UZ-FE has a log-style exhaust manifold that were prone to crack and create a "ticking" sound during a cold start. The crack is usually the size of a human hair and would subside shortly after the engine is started as the manifold heats up and closes the gap.

There were enough complaints to create a TSB (Technical Service Bulletin) but because it was not considered a safety issue, no recall was issued.

It's annoying and makes the Hundy sounds like a POS, the DT headers are going on here soon

 

[moooooooo]

there was another thread about cold morning startups i remember replying to.
Maybe expand your search a little bit.
From memory my comment said "... although mine is a manual ..." so search for that.
cheers
peter

 

[Topoguide]

there was another thread about cold morning startups i remember replying to.
Maybe expand your search a little bit.
From memory my comment said "... although mine is a manual ..." so search for that.
cheers
peter

The only two threads I know about are this thread and a thread called something like "knock, knock, who's there? Piston slap that's who". If you do a search on "piston slap" you should find it. I would post a link to it but haven't figured out how to do much more than browse and post on the iPad.

 

[04UZJ100]

The 2UZ is a noisy engine when cold. All is normal. some exhibit it and others don't.