If your engine knocks... no cause for concern?

[suprarx7nut]

Well I have a very occasional light knock/tick/noise coming from the engine area that only occurs when I'm accelerating. I've never been in a car with any sort of rodknock so I don't know if this is what the beginnings of RK sounds like or if its nothing related at all. I dont know if its the engine or a loose pulley or something else.

I cannot make the sound whenever i want. It has only happened 3 times in about 3 weeks. It does not make any unusual noises at idle.

If your engine knocks...
If you detect heavy knocking even when using the recommended fuel, or if you hear steady knocking while holding a steady speed on level roads, consult your Toyota dealer.
However, now and then, you may notice light knocking for a short time while accelerating or driving up hills. This is no cause for concern.

Can anyone explain to me what knocking they are referring to that is apparantly a part of normal operation?

Anyone had any sort of irregular occurance of tapping/light knocking before they had a visit from rod knock?

Thank you for any info

 

[Big Wang Bandit]

Maybe its the valves seating?

When I had my NA i got a knocking noise like it had to be rod knock, it was seriously that loud, and would seed up with RPM and would cut out at times, which in my head ruled out rod knock. Thought it was the valvetrain, but it ended up being a bad spark plug lead.

 

[cuel]

I think that the quote above is referring to spark knock when the engine is under load at low rpms. Do you have a knock sensor code stored? Code can be in the memory, but not setting the CEL.

 

[suprarx7nut]

I think that the quote above is referring to spark knock when the engine is under load at low rpms. Do you have a knock sensor code stored? Code can be in the memory, but not setting the CEL.

Going out to car to check right now...

I haven't had a CEL displayed, but I forgot that some codes on this car don't activate the CEL.


***EDIT: No codes stored except my TPS which i forgot to reset after I fixed it a month ago.

 

[GrimJack]

With the miles on your chassis, and only happening under acceleration, you'll probably find out you have broken motor mounts and it's the whole damn engine rattling!

Seriously, even if it is rodknock, at that level it's not a big deal, and it's not like there is anything you can do about it short of pulling the motor and rebuilding it. If it suddenly starts to get worse, shut it down and tow it home.

 

[JustAnotherVictim]

Check for loose parts/objects first.

 

[isnms]

I had an occasional knocking noise ... my crank pulley bolt was loose.

 

[suprarx7nut]

Ya, I have to make it through this week and then I'll have a week to look in to all engine parts and the mounts. I know my mounts are old and could easily be rotted out.

Lets hope its a loose bolt or something. Even bad motor mounts wouldn't be too bad. Rod knock would not be good, I still haven't paid off my tranny rebuild yet. (crosses fingers)

 

[Facime]

If you have a late 89 or later you have the round mounts and they are prone to breakage. Also dont discount the idea of the harmonic balancer being loose, I know someone who actually had one fall off while he was driving it coughstevencough*.

Low RPM, under heavy load, knock is fairly common. You can try raising the octane of your fuel. Also might want to check your base ignition timing.

 

[AJ'S 88NA]

What octane fuel are you using? And like mentioned, check your timing. Sometimes changing fuel brands will cause a little knocking especially a off brand.

 

[suprarx7nut]

I use shell 89 Its their mid-grade.

I first used only 91 (v-power) just as a precaution

I may start using that again...


My timing was checked 2 months ago and was dead on TSRM spec. I'll check it again, but not till next week.(when i'll have access to a timing light)

Thank you guys for your input, I really sincerely appreciate it.

 

[Facime]

91 or even better yet 93 would probably clear that knock right up. If you dont have 93 locally, get yourself a couple of gallons of avgas or race gas and mix some in with each tank.

 

[suprarx7nut]

Well I'll buy 91 from now on to see if that helps. An extra $0.15 per gallon is a small price to pay to attempt to fix a potentially large problem. It's worth a shot, i suppose.

How much extra would a turbo swap be vs a replacement N/A? :evil2: 400? 600? **edit, ok so it'd be much more than 600, but its damn tempting.

 

[Poodles]

back of my owner's manual...

"Fuel: Use only UNLEADED fuel, Research Octane No. 91 (Octane Rating 87) or higher. For improved vehicle performance, the use of Premium unleaded gasoline was a Research Octane No. of 96 (Octane Rating 91) or higher is recommended."

IMHO, if you have ANY mods you should be using 91 or better just for the safety... it's a lot cheaper than engine damage..

 

[Figit090]

is using 87 bad? i've been using 87 and i have noises...

what is this spark knock? could it be causing my loud knocks on starts where my rpm doesn't rev much? (warm starts) and rattling on cold starts? (high RPM revs)

 

[Poodles]

87 is bare minimum to not cause engine damage...

though you are N/A, I'd try running higher octane and see if it quiets down...

 

[suprarx7nut]

Well I changed my oil and checked handfuls of bolts for tightness and the noise remains. Though it really doesn't seem deep enough or heavy enough to be rod knock. Time will tell.

Another main constituent for my not-rod-knock feeling is that the sound is on the rare side. It happens once or twice every hundred or so miles. I have zero noise upon start-up as well. I want to say its a vibrational issue but the car feels very smooth and I feel zero vibration from the motor through the RPM range.

I have switched to shell v-power (91) and not noticed anything different.


NOTES TO ADD FWIW:

-Upon start-up my engine runs as smooth as it always has. I have never let the engine run any less than 1/2 quart under the full mark.

-The motor had a full rebuild 50k miles ago, but then the HG blew 20k ago. The PO said he had it towed immediately after the first overheat and the mechanic determined it wasn't necessary for a rebuild. I have receipts documenting the towing and HG repair as well as the engine rebuilds.

 

[Figit090]

what oil should we be running? i'm running 5w-30....i'm thinking going thicker might help?

 

[suprarx7nut]

10w-30 is what the manual calls for if you plan on driving in temps above 60F or so. IIRC the range for 10w30 is 0F and up and 5w30 is for 60 and below.

I use 10w30 Castrol GTX high mileage.