128keaton

Hello folks, its me again. Recently, I've experienced a small slew of issues with my 3VZE in my '93. First, its burning more oil than it used to. I can smell it burning just going down the road from my house (~1 mile). Its kept below 3k RPMS during this time. I'm also experiencing extremely low MPGs. I could get 13-14 it seems but its like 10 or something now. My personal opinion is that this engine is just real tired. 217k on the clock, obviously low compression, very slow to start, etc. I've considered doing a 5VZE swap but I am intimidated with the computer/wiring involved. I might do a further check-up on a local 3VZE, but the truck looks pretty rough.

RJR

Sounds like one or more cylinders has bad rings. If you want to diagnose it more specifically, pull all the plugs and post pictures of them here, then do a compression test on all cylinders, and maybe a leak-down test. That should help narrow down where the specific problem is.

How much oil are you using in say, 1000 miles?

128keaton

I've known the rings were toast for a while. I use about a quart every two/three weeks and I put about 78 miles a week. It has been a bit colder here than usual, but nothing below 65-70. When I get the time tomorrow I'll pull the plugs. The last time they were off, it was like 6 years ago and I remember them being a PITA to remove. There is honestly a bunch of things to check and work on, not a whole lot of preventative maintenance (other than topping off the oil) was done by the previous owner. It has had a single valve job done on it, a single set of new plugs, maybe an O2 sensor. The engine light code flashes 'oil sensor' even though the oil sensor is new and wired...

128keaton

ok. well I forgot to do the compression test. but I pulled all of the plugs and cleaned them, even #5. I found a large crack in the oil catch for the air intake so I fixed a vacuum leak. I also fixed the other leak in the pipe for the ISR mod. Now it idles even lower than it has before.. 400RPM... ugh its so discouraging since I shouldn't dump a bunch of money into it.

RJR

So, a quart every 150-200 miles. Not so good...

What did the plugs look like? What was special about #5?

128keaton

They weren't too bad. The last time they were out was in '08. They were all covered in white buildup on top of the ceramic. Yes the oil sucking is bad, I know. I just cannot put a new engine into it, not yet at least.








Any ideas about the vacuum issue being worse? I'm putting the stock Intake stuff back on to see if it's one of my fittings or something. I'm topping the tank off tomorrow and putting some of the valve cleaning stuff in the tank.

128keaton

So I have the idle problem more or less figured out. Too much vacuum causing the throttle to be too low. I need to adjust the A/C throttle so it allows the pulley to move further. I put some fuel injector cleaner in my tank today too.

128keaton

Ok I've gone roughly 200 miles without a fill up. Now I'm at a 1/3 of a tank. My vacuum issue is fixed, I put some fuel injector cleaner in the tank, and I cleaned my plugs. I haven't burnt near as much oil either.