Cold start "tapping noise"

[Dave777]

At about 4,500 miles my iQ started making a fairly loud, RPM related tapping noise, that sounds like valve tapping, but isn't. The noise disappears at about 120 F water temperature. The dealer mechanic confirmed the noise, recorded it and sent it to Scion/Toyota Regional or National for direction on what to do. It's been at the dealer for over 30 days, with the engine torn apart, as they wait for parts. Their plan is to replace the 4 "oil nozzles" that spray oil into the bottom of the cylinders, under the pistons. The direction to do this has come from some source at the Regional or Headquarters of Scion/Toyota USA. At this point no one locally is able to tell me why they think this is the solution, and I'm actively encouraging them to do so, as I'm not happy to be without my car for so long, and having it torn apart, without an adequate explanation. A possible explanation, researched on my own, is that it might be "piston slap," and as the engine warms and the pistons expand, the tolerances tighten and the noise disappears. This apparently has been an issue on some other Toyota engines, but I'm not sure it is on this engine. When the parts come in, who knows when, I'll report here on the results with the replacement nozzles. The part number of the nozzles is #15708. It's an inexpensive part, but requires tearing the engine apart, and isn't a part likely stocked at any dealer. More when I know more. Diagram for part #15708 Photo of the part

[Dave777]

And, for clarity, this is the U.S. iQ, 1.3 liter, gasoline/petrol, 1NR-FE engine.

Looking for insights or experience on this issue from anyone, worldwide.

[surfcitylocal]

Wow Dave, that's a lot of work for that small part. I hope it does the trick. Which dealership is it at?

[Dave777]

surfcitylocal, I'm in the Pacific Northwest, near Seattle, and am standing by for the dealer to do the right thing by me. Will post more when they do.

[Dave777]

The engine is out of the car, as well as the subframe and a multitude of other parts, awaiting the new oil nozzles.

Based on the time the car has been unavailable to me, and other factors, I'm pursuing a Lemon Law repurchase or replacement with Scion USA.

I have no doubt the mechanic will do a fine job putting everything back together, but I will have been without the car for over 50 days if they get the parts when they think they will, and in my State, that's considered unacceptable.

I've been exceedingly patient, and appreciate the work they're doing, and the loaner car I have, but it's time to let Scion USA take this car back.

And, for the record, at around 4,500 miles the noise simply got much worse. I'd originally reported it to the dealer and had them check it months earlier.

[Alphapenta]

Hello Dave, how did this turn out? hope they got your car running again,seems like a long time for the parts to come in? I was wondering if the oil was ever changed?

[ROCKLANDTOYOTA]

not sure where your located but parts are available within a few days for me and im in NY. im curious as too if oil was changed yet and if the 0W20 was used.....

[Dave777]

Thanks for your interest.

I never drove the car again. Toyota/Scion USA did the right thing, and swapped out my 2012 for a brand new 2013, no charge.

On another forum there's an owner with a similar issue, and they've put in a new short block, but he too is pursuing a Lemon Law replacement, due to the extensive time the car was in the shop. His was well under my 80 days, but still over 30 days.

My car started the noise at about 2,500 miles, so, no, the oil hadn't been changed yet from the original.

My new car has 1,000 miles on it and sounds perfectly normal. Hoping it stays that way.

[Alphapenta]

Thats good news! I'm glad they gave you a new car. I got my IQ in Sept.2012 and never got the engine over 4000 rpms for the first 1000 miles and then sucked that 0W20 crap out and used 5W30,the 0W20 I believe is for the higher mileage rating and will not protect the engine. Oil is cheap.

[mistergib]

Originally Posted by Alphapenta

Thats good news! I'm glad they gave you a new car. I got my IQ in Sept.2012 and never got the engine over 4000 rpms for the first 1000 miles and then sucked that 0W20 crap out and used 5W30,the 0W20 I believe is for the higher mileage rating and will not protect the engine. Oil is cheap.

You are correct....sorta.....

The 0w20wt that Toyota recommends and puts in the IQ's from the
factory IS for the pupose of achieving higher mpg. You changed the
0w20 for the 5w30 for purposes of protection and not mpg. I do agree
with one exception. I would recommend to you to use 0w30 synthetic
instead of the 5w30. The 0 winter-weight viscosity is not only good for
cold weather starting, but it also gets the oil circulating in the motor
faster in winter and summer, and as it heats up, the viscosity then
increases to the maximum of 30wt for the maximum wear protection.

The faster it circulates, the better for wear protection and the 30wt.
keeps wear protection to the maximum once its warmed up.....the best
of both worlds.