STUMPED: Misfire. General engine performance.
 

Please, contain your wrath.
Before I go and make another account just to join another forum, I have a general engine question.
Normally, I fix the hell out of stuff. In a short amount of time. I recently bought a 95 Toyota 4Runner 3vze(3.0l v6).

Long story short, it idles, accelerates, and drives like crap. I've replaced the entire ignition system, except the coil and ignitor. My timing light shows there is a signal heading down the wires.

THE GENERAL QUESTION:
I've unplugged each cylinder's ignition wire, but it still runs like crap even for every cylinder. For instance, I'll unplug cylinder 1, and it runs the same as if all of the cylinders were still connected. I'll unplug the remaining 2-6, one at a time, and it never changes the idle or performance. Haven't found any vacuum leaks.

Any suggestions guys? I just really don't want another forum account, I have too many.

ok then. so *no difference* in the way it runs at all?? or just not that noticeable??

have you tried checking the ignition timing?? if the timing is too far off then that could make it run like big fat poop.

get that set to spec, then go from there.


does this have a lot of parts thrown at it??




df

Aside from what you are checking, possible crappy gas? possible fuel filter/pressure issue? FPR or lines to it bad? Airflow not blocked? Does it have the equivalent of a MAF or AFM? still good?

If I think of anything else, I'll add in.

Good luck! :cool:

check engine light on?? also have you checked for codes??

egr function?? (can cause issues)

plus 1 on the fuel pressure check.

lots of little vac lines and impossible plenum design on asian v6's...hated working on these things....


df

Sorry guys. That description I gave was awful.

I reset the timing to what it should be, 12deg. I guess the PO advanced it so it wouldn't idle so rough. I've checked coil resistance too.

I did get a code out of it! Finally! I'm still checking fuel pressure and compression tomorrow.

Code 14 for igniter, igniter circuitry, or ECM.

I guess I'll post up what I found. Maybe somebody will find it through Google one day.

Coil's do fail, How old is it? Thinking you might have to find someone with a dwell meter or if your DVM has one check it on that.

When you say ignitor what is that? I don't know toyota's maybe it's something as simple as a index wheel that sends the spark to each plug lead.

Low compression #5 guys.. FML

Low compression....Bad head gasket? do you have a leak down tester?

I don't. This weekend when I go back to my parents, I'm going to drop some oil in the cylinder to see if it changes any. It was pretty low, though. The rest were ~160, #5 was at 40. The thing is, the heads and headgasket both look brand new and it's in time. The timing belt and water pump have also been changed (FWIW, this engine is non-interference). The PO doesn't admit to knowing anything about a headgasket or anything. Also has a new water pump.

I guess it's possible that a valve isn't adjusted right, but I would hope that wouldn't drop the compression that much.:confused:

All I know is, I'm in college on my own, and $2000 was a ****e load of money. Last Toyota I ever own, right here.

What type of toyota? With 5 out 6 cylinders at 160 psi and the other at 40 psi that is a very big disparity.

Any oil in your coolant system or coolant in your oil? Could be a cracked head as well. We need a little more details.

Mileage, what type engine and so forth. Known maintenance on the car?

I put the engine type in the first post. 3.0L V6, 3vze, 1995 4wd 4runner.

237,000. I have zero knowledge of any previous maintenance, as you can probably tell from what I've said before. All I know is, it looks like it has new heads (they're VERY clean), I can see the corner of a headgasket that looks really new, and the timing belt and water pump look new. I've replaced the plugs, wires, cap, rotor, because I was getting a "Code 14" which points to a bad igniter/igniter circuit, but it's probably just detecting the massive misfire I have right now. I've also checked the engine timing.

No coolant/oil mixing, no pressure building in coolant lines, etc. Anything that would signal a bad headgasket, I'm not getting anything.

It very well could be a valve is out of adjustment (but I wouldn't think it would cause THAT much compression loss), or it could just be it was a junk head to begin with. I've caught the PO in a bunch of lies already, so he probably knows what's wrong with it. He won't talk anymore. Found out yesterday he had been riding it with a stolen dealer tag, so there's no telling what else I'll find in this thing.

I'm going to drop some oil in the cylinder this weekend to see if there's any change in compression. That low of compression is definitely an issue though.

Looks like I'm just going to have to take this one on the chin. :frown: Thanks for all the help and not butchering me because it's not a Ti though. FWIW, I ABSOLUTELY F'ING HATE this engine. There are way too many vacuum lines in this thing.