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DaveInDenver
07-23-2007, 01:43 PM
Driving back home yesterday afternoon I started getting a pre-detonation. I would get this occasionally with the old engine, but this was a bit worse. I've got about 1400 miles on the engine now and have not had any indication of this until yesterday. Don't know my exact compression ratio, but since the block is factory fresh and the head is stock height, I would expect a stock compression ratio of 9.3:1, maybe a touch lower because the combustion chambers were enlarged by about 8cc each when the head was worked on (so I have a 2398cc engine, not a 2366cc like stock). I run 87 octane all the time. I got about 3/4 of a tank of gas up in Cheyenne at an Exxon (I usually use the same Conoco in my neighborhood, probably something like 80% of my fill-ups so far have been at the same station).

The engine would get the pre-detonations rattle at mid throttle, nothing wide open and nothing with the throttle at 1/3 or less. Only at the position I needed to do 65 MPH in 5th gear... Say giving it roughly 50%-75% of the throttle at 3000 RPM.

Trying to figure out why this is happening. I haven't had a chance to pull the plugs yet, but when I pulled them for the roughly 1000 mile service and check they were pretty pale. I think the engine is running pretty lean. The air flow meter is not adjusted, still stock position. The plugs are Denso W16EXR-U, the stock plug heat range.

So before I go mucking with the AFM, I want to throw it out there. How can I tell if my engine is running too lean? The injectors are all clean as a whistle (they were serviced during the engine build). I will assume that my combustion chambers are in good shape and that I'm not getting a HG leak (if it matters for a pre-detonation). Running a stock ignition with the MSD 8222 coil (yes, Rudy, I'm running the MSD) with 5* BTDC base idle. The knock sensor I though was working fine, although after yesterday I'm not so sure. Stock OEM air filter and intake. The throttle body is stock, not bored bigger or anything. The head is ported, I have oversized valves, a more aggressive than stock cam and a header. So I am flowing air better than stock.

The air temperature was H-O-T, no doubt it was 100 and so coming up off the asphalt it had to be a lot hotter than that (we were coming down US85 from Cheyenne at 4PM). A/C on or off, no difference, although the truck was loaded, so the engine was working.

So the two things I've come up with is the next cooler heat range spark plug and adjusting the AFM for a slightly richer mixture. I think based on the way the plugs were light colored that a cooler plug might only mask a too lean mixture, if that solves it. I do still need to replace the engine coolant temp sensor (this could easily be part of the problem IMO, too). My O2 sensor is not brand new, but it's not failed. No codes stored last time I checked and no CE light.

Anything else I'm missing?

Rzeppa
07-23-2007, 08:34 PM
Sounds like you're on the right track. The plugs tell the story. Too lean most likely. Cooler plugs are a band-aid.

SteveH
07-24-2007, 09:59 AM
I suspect timing and a hot day. If premium fuel doesn't eliminate it, then you will have an idea of the problem being bigger than just having your timing off a few degrees. My FJ40s never liked running more than a few degrees advanced over stock at 7000'. Some engines can tolerate much more spark advance at high elevations. Try setting your timing to the stock setting.

Red_Chili
07-24-2007, 10:48 AM
DO NOT MUCK WITH THE AFM. Many engines have died as a result.
Retard the timing a bit. You probably got a different brand of gas as well? Ethanol content? You should not need 91.

The knock sensors are pretty worthless FWIW, and will not retard to prevent preignition. Be sure to check the condition of all your vacuum lines.

Ted will happily give you advice if you call him, too. He has been there, done that, with the 22RE. The O2 can be marginal and not set a code FWIW, and you can get the OEM one much cheaper than from Toyota at Sparkplugs.com. Use the N-D O2 sensor.

Red_Chili
07-24-2007, 11:33 AM
Destroy top ring lands. If you are monitoring with an A/F meter and are careful to hit stoich, that is better than most, but the ECM on the 22RE is from the early Pleistocene and is not that precise. Rich can be very bad too. 3FE is not a 22RE.

So what did Ted say? He has the most experience with his valves.

Red_Chili
07-25-2007, 11:02 AM
Recheck your valve lash. Never know, could've seated a bit. 22-RE v. 3FE comparo was just to say, because someone has done it successfully and had good results on a 3FE does not mean you will on a 22-RE.

subzali
07-26-2007, 07:29 AM
what are factory specs for compression on a 22RE?

Red_Chili
07-26-2007, 08:38 AM
My son's had 170 (and not a lot of carbon to fake the high number) at 70K miles. So yeah, since PSI is relative to ambient, it is certainly achievable. Your rings have not broken in IMHO, did you do the Motoman break-in? Or did you take it too easy to start? Are you using synth? Burning oil?

Check the compression hot.

Always adjust the valves hot. A royal pain I know. They *should* be tighter hot. I've not always followed my own advice on this one.

Red_Chili
07-26-2007, 09:19 AM
I don't think you're stupid at ALL, hope you didn't take any of my comments that way...

I don't doubt your observation on hot lash either, though every motor I've worked on has been opposite. Can't say that I paid all that close attention to the 22RE in that respect though.

SteveH
07-26-2007, 10:01 AM
Deduct 3% per 1000' of elevation for compression. There's nothing wrong with 135-140 for numbers in Denver on that engine.

Red_Chili
07-26-2007, 10:56 AM
Not for used, but this is a new shortblock- I've gotten much higher numbers.

Red_Chili
07-26-2007, 11:57 AM
Wouldn't hurt to retorque the head too, that almost assuredly is not it, but it's time.

Red_Chili
07-26-2007, 02:56 PM
IIRC cold, but follow the manual.

subzali
07-26-2007, 06:50 PM
That could be possible if you went with one of those aftermarket chains that is super super tight and you have to rotate the cam gear slightly to get the chain on right. I didn't get any special chain for mine, and it was pretty obvious which which tooth it had to line up on. I guess that could cause the symptoms you're seeing, but geez that's a lot of work to redo, check, and then potentially take apart again to fix if that adjustment is actually off. Just a reminder: did you replace the timing chain on the other engine, the one you said was pinging in a similar manner?

Red_Chili
08-26-2007, 11:38 PM
They are not unseated due to needing cleaning; in fact, quite the opposite. So far your measurements don't strike this inexperienced novice mechanic as out of whack. Any time you spray oil in the chamber your numbers will go up. With 2K miles on it, how could they possibly be gummed up?

MOA might actually inhibit ring seating, like synthetics will. Plain dyno oil till they break in. They aren't seated.

This doesn't add up to your detonation problem though. Can you verify for sure your cam timing is correct, like, perhaps with a degree wheel or something? I would think Tod's diagnosis is still the most reasonable.

For some of us detail people, we can end up chasing a problem around and around until we are lost in a sea of details and end up thoroughly confused. Don't ask me how I learned that one, or how I continually need to relearn it. Sometimes the simplest and most obvious explanation is also the right one. Check your cam timing, and not just the dots.

Such stories I could tell, whether chasing a mechanical problem or looking for what seemed at first to be a ground fault in control system field wiring, but which also seemed to be a voltage source from another system which I chased for two hours. It was a ground fault on an alkali surface in the presence of water, zinc, and copper, creating a 'battery'. But it was a ground fault plain and simple.

Or the time I disassembled a motorcycle that wouldn't start. It was out of gas.

Need more dumb stories? :lmao:

Ockham's razor applies.

A mail order adjustable cam sprocket might also! After of course determining through direct measurement whether the cam timing is precisely correct.

Volcom
08-27-2007, 11:42 AM
Ted didn't include a cam card.

That's one of the only things I didn't like about getting a cam from him. My dad was shocked when he was looking for a cam card and I told him there wasn't one. I had to email Ted for the specs. These were the only other specs I could find on the 268
""Our most popular RV cam profile, It is our unique lobe shape that yanks your chain, .425" gross valve lift assures easy dropin fit with your stock springs and rocker arms, nice early powerband for the big 4 X 4's, 4 Runners, or for a cool mix of offroad, street and highway use...With NO concerns regards emissions tests. 268 advertised, 218 @ .050", 110 lobe timing."

Which cam do you have? I thought you had the 268 but didn't see it in your posts.

DaveInDenver
08-27-2007, 12:13 PM
That's one of the only things I didn't like about getting a cam from him. My dad was shocked when he was looking for a cam card and I told him there wasn't one. I had to email Ted for the specs. These were the only other specs I could find on the 268
""Our most popular RV cam profile, It is our unique lobe shape that yanks your chain, .425" gross valve lift assures easy dropin fit with your stock springs and rocker arms, nice early powerband for the big 4 X 4's, 4 Runners, or for a cool mix of offroad, street and highway use...With NO concerns regards emissions tests. 268 advertised, 218 @ .050", 110 lobe timing."

Which cam do you have? I thought you had the 268 but didn't see it in your posts.

It's the 261C cam. Forgot to ask for a cam card, but when I was shopping he emailed his specs for head and cam.

The valves are O/S, 1.803" intake and 1.481" exhaust, guides are bronze, bowls are increased 8cc.

Cam spec is 110 lobe center, 222 duration @ .050" lobe lift, gross valve lift .410". Lash setting is minimum of .007" intake and .009" exhaust.

Red_Chili
08-27-2007, 01:58 PM
Other things I read say that you don't want them to seal that quickly, because then the engine is too tight and you won't get the longevity.
I call bull on that one. The motor was made to work at operating pressure. And the 22RE was not the tightest motor made for that matter.

Sustained speed will not seat the rings nearly as well as full throttle. Hammer it.

The rings will seat. Unless the Toyota factory monkey lined up the gaps?:rolleyes::eek:

Red_Chili
08-29-2007, 11:28 AM
"4 or 5 mpg...." :eek::eek:
Don't do anything jacked that could screw up the warranty coverage.
I would not assume the assembly is OK.

Red_Chili
08-29-2007, 12:13 PM
What the heck am I supposed to do? Drive it hard or not? I'm so confused. One time I'm being too easy, next I'm being too hard. Drive it like normal. Drive it like you stole it. Drive it like you have eggs in the back. Drive it like a teenager. I think my head's gonna explode. Ted tells me to take it to the track and run it through the traps, so I drive it like I'm drag racing and now that's wrong.

:lmao::lmao::lmao::lmao::lmao::lmao:
I mean using Ajax or lapping compound or weird oil or anything like that. Something JACKED in other words. Drive it like all of the above, you won't hurt it unless it's already hurt.

Your problem is likely a Toyota assembly issue- so much for OE quality. It happens. OE is no guarantee of quality and aftermarket is not junk. Both were made by a man (or woman, maybe...):cheers:

That is what warranty is for.

Red_Chili
08-29-2007, 12:14 PM
I tell ya this much, this is the last engine I ever rebuild. I swear I think I'm getting both an ulcer and an embolism.
Howzcum? You are letting out all the accumulated demons from the rebuild underworld, it's all good from here! :blah::lmao:

Uncle Ben
08-29-2007, 12:59 PM
DRIVE IT! If it fails they will warranty it but just drive it! Your very poor mileage is not right! It sounds way to rich will also keep the cylinders washed and they wont seal. Spend a few bucks and take it to someone that remembers how to work on stuff without plug in diagnostics!


The idea that a Japanese-assembled Toyota 22R short block is built wrong for some reason bothers me. Whenever I've let someone else do something, it invariably has been !@#$'ed up. As a control engineering student, I worked an internship at a Toyota plant back in 1993 (the Toyoda-Gosei in Perryville, MO) and seeing how much time and effort they put into QC (what they called kaizen, a TQM philosophy) impressed me. And this was in rural southeast Missouri 15 years ago and we were just making steering wheels and air bags, I would have guessed the engine plant at the Myochi factory would have been even better. Guess you really can't really trust anyone to do anything right anymore.

Uncle Ben
08-29-2007, 01:17 PM
Nah, the mileage drop is only because I have been pushing the gas pedal to the floor. Up until this week my mileage was pretty typical, around 18 or 19 MPG. I am running W.O.T. when starting and winding it out from every red light and stop sign, which kills my mileage. I have been running really lean and bumped the AFM 2 clicks to bring the mixture a little richer. So far it's been happier with that, no detonation in 2 weeks and it feels a little peppier on the highway.

Kewl! :cool: :)

Red_Chili
08-29-2007, 02:21 PM
Hold on, don't write off UB's concerns too quickly. I know of several 22RE motors that have grenaded ring lands due to moving the AFM a couple clicks rich. A 22RE getting 4 or 5 mpg is NOT normal and if too rich WILL wash the oil off the cylinder and grenade the ring lands. No warranty. This falls into the hinky mod category.

I too understand and admire Kaizen. That's why I am a Toyota fan and interested in process control too. They wrote the book. But they will also tell you that manufacturing that is perfect is doomed to fail because a toilet seat will cost a half million dollars to produce. ANYthing is possible.

Trust.

But verify.

That too is Kaizen.

Remember, the really desirable jobs at Toyota are not making out-of-production engine blocks for a 22RE. In fact, they may have outsourced it.

You can't trust anyone to do it right? Sure you do. Every day. But there are certain things that cannot be assumed and must be verified.

You draws yer cards, you pays yer dues, you take yer chances. Part of life, don't get an embolism over it!
A man can fix it. :D

Red_Chili
09-10-2007, 09:39 AM
The idea that a Japanese-assembled Toyota 22R short block is built wrong for some reason bothers me. Whenever I've let someone else do something, it invariably has been !@#$'ed up. As a control engineering student, I worked an internship at a Toyota plant back in 1993 (the Toyoda-Gosei in Perryville, MO) and seeing how much time and effort they put into QC (what they called kaizen, a TQM philosophy) impressed me. And this was in rural southeast Missouri 15 years ago and we were just making steering wheels and air bags, I would have guessed the engine plant at the Myochi factory would have been even better. Guess you really can't really trust anyone to do anything right anymore.
Just FYI, Justin told me they had a Sequoia in for oil consumption and some blue smoke. First they found a valve guide seal improperly installed, figgered that was it. He then sent me a pic of a piston and asked if I knew what was missing...

Had to squint, but it looked like a missing oil control ring.

Yup, he said. From the factory. 1200 miles on the motor. The owner was a Ford guy who was not confident in Toyota quality. I think he will not be bestpleased.

Red_Chili
09-10-2007, 10:32 AM
I don't have the experience with new motors enough to say. Seems fishy though when I got 170 psi on Justin's 80K motor when I bought it and it was not due to carbon. I have consistently gotten 160+ at this altitude with low mileage 22REs. I think my 150K 22RE got around that, even, IIRC.

Red_Chili
09-10-2007, 12:30 PM
Call Scott Rill at Burt Toyota. He is your bottom line. Tell him I said so too. FINE man.

wesintl
10-22-2007, 11:28 AM
I believe it's grams per mile...