I can't figure out if it's the valves needing adjustment or just noisy injectors. Or worse, a rod knock. It has 170k and has been doing it ever since I've had it (about 10k) so I'm assuming it's nothing too bad. It also eats oil. 1 quart of 10w-40 Full Synthetic Royal Purple every 1000 miles. At that rate, I don't even have to replace the oil!

 

consider having your fuel system cleaned. if im not mistaken, since its a timing belt, there is no adjustment for the valves. someone please correct me if im wrong. could be a rod knock, but i would look into an internal engine cleaning of the air plenum, injectors, throttle body, crankcase, and the rest of your fuel system.

 

Wrong. It's a PITA though. Requires tearing the upper intake off, then the valve covers, checking the valve lash(a.k.a. clearance)with a feeler gauge set, special tools(2) to remove the adjustment shims, micrometer to measure the shims, checking those measurements on the shim thickness chart to get an idea as to what shims are needed to correct the clearance, ordering the new shims from Toyota(their the only people that have them)and reinstalling those.

So yeah, the injectors tick so loud I can clearly hear it in the cab with the doors closed and the windows up. Cleaning them, loads of injector cleaner via the fuel tank, makes no difference. And I highly doubt having them professionally cleaned on an injector cleaner would work any better to stop their ticking. That's just what they do. Many people who've been around these engines can attest to that being so. I recently adjusted my valves to specs. They were WAY loose too. Made no audible difference.

A quart every 1000 miles ain't too bad, ain't great either(esp. if your running synthetic which is not only $$$ but has more tendency to slip itself into the combustion chamber). Probably the valve stem seals. I noticed a HUGE difference when I changed those out with the blown head gaskets. Went from alot to very little. It probably burns about 2/3 of a quart every 3000 now at best, dino not synth.

 

thanks, i stand corrected. good post.

 

Oh ya, noisiest motor I have ever owned. I did a rebuild on mine and had the injectors serviced, they made more noise after the servicing than before. I think they run quieter when they are clogged up....

After my rebuild I had to be sure about the valve clearances, so I took the plenum back off, pulled the valve covers and checked them after 1k miles. They were fine, the clearances were in tolerance. On mine, if I take an automotive stethoscope and listen to the injectors, you can hear the tick.

I saw one guy who pulled the plenum and put pipe insulation around each of the injectors to quiet them down. I have not gone that far yet.

 

Timing belt doesn't equate to whether a valvetrain is adjustable or not. That has to do with the valvetrain design. A friend of mine has an '84 VW Westy with a 1.9L 4cyl. The valves have hydraulic lifters and are not adjustable. Not sure if all hydraulic valvetrains are not adjustable. Just sayin' his aren't and are designed quite differently than our Toyotas.

BTW, the ticking injectors is quite normal. I think that has a lot to do with the fact they're are simply solenoids and work much like any relay only at a very high rate of speed. I wouldn't use any type of insulation around them, though, as they do need to be able to dissipate heat. Heat's not good for the coil windings. It'd be best to just insulated the hood if it still doesn't have the factory insulation.

 

I thought about that too when I read about the insulation, but, they are also cooled by the fuel that is running through them. External electric fuel pumps are the same way, the fuel pics up the heat as it passes through. You might be heating up the fuel more than you want if you insulated them.

Seems like too much work for something that is just mildly annoying. It annoys me most when people ask me about it, everyone thinks it is an exhaust leak. Not, just noisy injectors.

 

Probably not so much the fuel for reasons you've stated. The internal windings still heat up to a degree, though. As well, all the transferred heat from the manifold can't be quelched by fuel. There again, the insulation might actually help with that. Meh....I still just wouldn't do it....lol!

I don't hear my injectors when I'm in the vehicle even with the windows down. So, it's no bother to me at all.

 

Good to know. I thought it was just injectors. Probably more concerned about a quart of oil being eaten every 1k. I know I pulled the plugs and the rear 2 passenger sides had oil on the threads... looks like headgasket leaking oil into the combustion chamber. It's the first half of 95 year, non tacoma. They fixed the HG issue that year if I recall correctly.

 

Could very well be the valve guide seals also. If the seals are wallowed out oil will leak down the stem and onto the backs of the valves. When you shut it down you can get a good amount of thin/hot oil leaking down the valves.

At startup, do you get puffs of oily smoke out of the tailpipe, for a very short period of time? Especially after a hot shutdown and then starting back up 10 to 20 minutes later? That would indicate the valve guide seals and/or guides are worn out.

Do a compression check on it. If that looks good, do a leak down. If that all checks out then the oil is most likely coming down from above, past the valve guides. Then, a top end job is in order.

Good luck,

Mike

 

mine does niot tick at 193xxx miles. i burn through about a 1/2 qt every 200miles.
until you fix it man, i wouldnt waste your money on the royal purple. save that for a modded engine. or hp application IMO

 

yes....lifter