Hello,

IÆm trying to resolve some knocking in my truck under load. I have a 95 4x4 22RE with 66K original miles on a stock motor. In the last year I have replaced the plugs, wires, rotor, dist cap, hoses, thermostat and flushed the radiator. The truck has been well cared for and the oil has been changed every 3500 miles. The knocking isnÆt causing a CEL but it bugs me. Other than the knocking the truck runs fine. I average about 21mpg in town. It has been happening for a while now (Many tanks of gas). Higher octane does seem to help some but it still doesnÆt cure it. I have both the Factory Service manual and the Haynes Manual. As a result of reading them and searching the forums I have developed some questions that I hope other Toyota enthusiasts might know answers to. So here goes.

1. Is the knock sensor on the side of the block by the oil filter? The FSM says to check the Knock Circuit first but then doesnÆt tell you who to do it. My understanding from reading the boards is that they almost never fail. Anyone else hear that?

2. My understanding is that at altitude knocking is less of a problem than at sea level. I live in Albuquerque (5280ft) so I am thinking the truck would knock itself apart if I take a trip to the beach. Can anyone confirm that?

3. From what I gather from the manuals; the cure involves reducing combustion temps or retarding timing. So for reducing temps I can try cooler plugs, a cooler thermostat but if I retard the timing at idle that doesnÆt mean that it will stay retarded under throttle does it? IÆm a little unclear on how timing advance works.

4. Any other suggestions? The FSM says to check in this order: Knock sensor, fuel, plugs, egr, timing, radiator, cooling fan, thermostat, water pump, ECM. I donÆt think it is carbon build up in the cylinders. IÆm going to replace the EGR this weekend (haven't done that yet). If that doesnÆt do it what would you try next?

Sorry for such a long post. I realize that ôhelp meö threads are not nearly as fun as ôcheck out this cool new 4x4 mod that I didö threads. I am hopeful that I will get to do some mods soon and that I will post more interesting threads in the future. Any thoughts or ideas are greatly appreciated!!!!!

My '91 22re, 4wd pinged(light knocking, right?) always from when I aquired it at 142K miles here in So. California, and when the service guys swapped in a rebuilt long block at 164K miles, and bolted on all the old EFI and engine control peripherals, it knocked(sorry, pinged) EXACTLY the same as before. Flash forward 3 years to now...I put regular gas in it(which makes it ping like crazy) and take it to my local Toyota dealer. The sevice tech AND his boss take it for a test drive, come back and report: 'Oh, yeah, that's normal. Don't change a thing.' Same as yours, higher octane gas makes it less, retarding the spark advance makes it less. Interestingly, when I drove it to Utah, it stopped pinging with the first tank of Utah gas I put in it, and started pinging again when I started putting Arizona gas in it. Cal. gas = Az gas, more or less, I guess. I'm tired of trying to stop it from destoying itself. Cheers, Keith B.

The first thing I would check is the timing. The idle timing is just the starting point, unless something seriously is wrong it'll advance or retard as needed automatically.
EB has a killer post on getting more power out of a 22r/e:

http://www.4x4wire.com/forums/showf...part=all&vc=1&PHPSESSID=

and an old post from the ORC board:

http://bbs.off-road.com/ubbthreads/...in=155252&Search=true#Post658728

Mark

I would call it light knocking. It is good to hear that other trucks seem to have it too. I found this link (knock sensor mod )that I am curious about. Basically it says that the signal from the knock sensor is being drowned out by other noise. I might try the suggested mod and see what happens. The mod was done on an 88 but things may not have changed much for my 94. I hope the knock sensor is the one by the oil filter.

Thanks for the links on increasing performance. Lots of good reading in there. I'll check the timing again. I've checked it in the last year or so and I seem to remember that it was 5 degrees with the jumper on (not positive though).

How much power am I loosing with the knocking? Seems like having fuel burn before it is supposed to would kill some power.

Check your timing.