Last post on Dec 04, 2013 at 8:09 PM
You are in the Toyota Sienna
What is this discussion about?
Toyota Sienna, Van
Go to NHTSA to file a safety complaint.
Or call Monday-Friday (8 am to 8 pm ET) (888) 327-4236 TTY: (800)424-9153
#91 of 109 Re: Piston Slap Is Normal [stower17]
Oct 26, 2012 (8:12 am)
There is one (or more) problems with your analysis of Toyota engine piston slap.
Piston slap is not the same for every Toyota vehicle. Some Toyota engines develop the issue sooner than others. Also, the amount of time it takes for the slapping to dissipate varies also. These two inconsistencies alone are solid proof that Toyota engines do not have consistent piston/cylinder tolerances.
The Toyota factory rep told me (on Dec 2011) that it is normal for their engines to develop piston slap (at what point this will happen was not specified) and that it is normal for them to sound like a diesel engine for the first 10-12 minutes of driving (depending on outside temperature).
If your commute is only 10-12 minutes like mine is, you will have a knocking engine the whole way to and from work.
*** This is not acceptable in my opinion. ***
#92 of 109 Re: Piston Slap Is Normal [gobubba]
Oct 26, 2012 (8:39 am)
You are probably correct. Short skirt pistons are so 'on the edge' that minor manufacturing tolerances and matching to cylinder bores, the exact fit and balance of piston rods and wrist pins, etc., that some have it from day one, others develop the noise over time, and I'll bet that the noise varies from cylinder to cylinder within any engine.
Here's the thing. If you own a Subaru, you've probably lived with piston slap for 15 years. Corvette - famous for it. Go to the Dodge board - yep. This is the direction of the industry, as they attempt to trim reciprocating mass. And with all the complaints over the years on the Subaru boards, there seems to be little evidence of real engine damage other than a little scraping of the moly coating on the skirt, with little or no evidence seen on the cylinder wall. I've seen no change in oil consumption in 100k miles on my Subi, and it clatters like a diesel on a cold morning. My Sienna (2008 - 2GR-FE) does also.
I understand your feeling, and I don't like it, but I've learned to live with it.
#93 of 109 Re: Piston Slap Is Normal [fibber2]
Oct 26, 2012 (5:26 pm)
Here is my my view on Toyota's piston slap issues. They should be up front and tell potential customers about the "normal" operation of their engines.... They will develop piston slap which causes the engine to sound like a diesel for the first 10-12 minutes of driving (from a cold soak engine temp). They should also let them know that if one of their engines does not develop piston slap.... then it is considered "abnormal". If the customer still wants to purchase the vehicle, that is their choice.
My wife and I have personally owned 14 different cars from 6 different manufactures (including a 1993 tercel), none of which had any audible piston slap whatsoever. I am not counting the 2008 certified preowned Highlander that we kept for one tank of gas and then forced the dealer to buy back due to piston slap.
#94 of 109 Re: Piston Slap Is Normal [gobubba]
Oct 26, 2012 (6:23 pm)
No doubt if that Highlander was a V6 model, it had the same 2GR-FE engine as in your Sienna.
I cannot argue with you on this, as I really agree. Piston slap is one of those universal dirty little secrets that nobody wants to acknowledge or openly discuss. I'd love to see a manufacturer issue a TSB that fully describes it, and what the 'limits of acceptable' noise level and duration is. They may exist, but I've not seen one. But yes, it seems to be the 'new normal'.
In my opinion, 10-12 minutes seems like a long time. As I said, both my 2002 Outback and our 2008 Sienna sound pretty bad for a few minutes, but you can hear it fade away as the engine(s) warm and smooth out.
#95 of 109 Re: 2002 Sienna LE - ECM Replacement [sphornets]
Nov 09, 2012 (5:28 am)
What octane fuel have you been running? I recently had all that fixed I hope. But prior to that, I either disconnect the battery or take it to an auto part store to reset the light. The light will stay off as long as I run high octane fuel with no ethanol.
#96 of 109 Piston slap engineering
Dec 02, 2012 (9:16 am)
GM addressed the reason for piston slap in the 1990's and I believe Subaru did as well. It was mainly for fuel economy. Engines designed with piston slap have short skirt pistons generally and the pistons are considerably smaller than the engine bore they operate in until the engine warms up. As the engine warms, the pistons expand and make a near perfect match with the cylinder bore. Engines develop piston slap at different mileages and that is due to many factors, non of which are to be concerned with. As for manufacturers placing a warning or notice in owners manuals about piston slap; probably won't happen. An owner with rod knock or other engine noise might be under the impression the noise is normal if the owners manual said that loud cold engine noises are normal, making the manufacturer liable. Most manufacturers are going this way for fuel efficiency so now more people are aware of it and are concerned with the slapping noise. It's a little frustrating at first to listen to but you get used to it. My slapping engines have 97,000 mi, 248,000 mi, and 153,000 mi. No effects on longevity! Happy driving!
#97 of 109 LS1 engines
Dec 02, 2012 (9:40 am)
Just wanted to add that my father and brother have several LS1 powered camaros and corvettes. All have piston slap and some go away once the engine is warm and some continue slapping the whole time the engine is running. I don't understand how that is but some of their cars are going on 15 years old with over 150,000 miles and still run like the day they rolled off the line. My aluminum gm v6 engines, my 2.2 ecotec, and my silverados all have it. It is a mystery for sure.
#98 of 109 Regarding sludge
Dec 10, 2012 (7:14 am)
Regarding sludge, the only thing I've noticed is in my oil fill cap I see some slight reddish brown pasty gel. The engine probably burns about 1/2 to 1 quart per 5000 mi. So, just to be on the safe side, I've just started adding a dose of Seafoam(r) additive to the crankcase to keep the internals clean. The gel is not as noticeable as it was before.
#99 of 109 Re: Regarding sludge [trendao]
Dec 10, 2012 (7:21 am)
I would try using synthetic oil and/or shortening the oil change interval.
#100 of 109 2008 Error Code: P0015
Mar 24, 2013 (6:18 am)