dan0o0o

Hi all,

I'm somewhat new in the Toyota world, and was wondering if i could get some insight into my 94's performance, or lack thereof.

Here's the info:

The truck only has 115k on it. I bought it last summer with 108k on it. When I first got it, it would get about 350mi/tank depending on what kind of driving I was doing. Now, i'm lucky to get 200. The truck runs 31" BFG AT's, and has a k&n air filter. Oh yeah, we're talking about the 22-RE motor, 5spd tranny, 4wd model

Symptoms:

A few months ago, I noticed the idle speed as a little low, about 650rpm. I upped it to about 900. I noticed that the idle was a little rough, maybe knocking a little bit. It leaks oil out the back of the motor. It's obviously coming from the valve cover, and it's unconfirmed whether it's coming from anyplace else, head, rear main, etc. I keep it filled, and there is no evidence of it burning or mixing with coolant. Today I took out a plug and noticed that it was rather carbony, moreso than usual.

I've replaced the distributor cap, rotor, plug, wires, fuel filter, and cleaned the k&n. With all that, I still get 14mpg. Not cool.

My compression tester is broken, so that's on the schedule for the weekend, as well as a timing check.

The truck seems to run ok, it's not really peppy, though. It doesn't miss, to my knowledge.

Does anyone have any other ideas?

Thanks in advance.

Dan

zedex

Check all the plugs. Remember what plug came out of which cylinder. If any of the plugs are oily and black you have either valve or ring problems. If plugs are black carbony, not wet, you have probably fuel issues. Buy a new compression tester and test each cylinder wet and dry. You can narrow things down pretty fast doing these things.

ringo234

Check the O2 Sensor, I made a big difference in my fuel consumption. My check engine didn't come on but the O2 sensor was definitely bad.

Andy

HBoss

How do you check the O2 sensor exactly? I thought it was a "check engine light/replace" thing. Otherwise you can't tell it's bad?

ringo234

Well I found out mine was bad because It wouldn't pass smog.
The technician had a portable oscillascope. The sensor is supposed to fluctuate between 100 and 900 mVolts. Mine was putting out a constant 500 mVolts.

So unless you have an Osillascope you'll have to have a shop check it for you.

My Check light did not come on. But replacing the sensor increased my Mpg by 33%.

Andy

Bumpin' Yota

I think my O2 sensor wend out on my 3vze....upon accelleration there is a sulfer/ammonia smell from the exhaust that is REALLY pungent. MPG went from ~19 on the highway to ~14 if i DONT gun it at all - otherwise 12-13. It was even lower before the FIPK, but came up a little after I installed that. Also, the engine seems to bog at the bottom of the next gear when I change gears at WOT.......

How much does it cost to have the O2 sensor checked?

Steve

HBoss

Didn't mean to barge into the thread, but thanks. My fuel economy is crap lately and the only things left to change are the fuel filter & O2 sensor(s). The latter being quite pricy, which is why I wanted to know if it could be checked.

dan0o0o

thanks for all your suggestions.

over the weekend i did end up checking the compression, and it's pretty good, 140psi in all 4 cylinders. I also replaced the valve cover gasket to stop the pesky oil leak. I'm going to get the O2 sensor looked at later on this week, as well as the timing. I'm putting my money on the 02 sensor though.

joez

dont foget to check/clean the injectors, and check all vaccum lines for any possible leaks. my vacume leaked resulted in my truck having to be three-footed b/c of no idle control. check your mafs too.