91 4runner V6 3ltr problem

91rv6

New member
Just looking for some answers and maybe solutions before I go to the mechanic and spend the $. Over the last month my v6 4runner has had an intermittant issue.

The issue being, starts fine and drives.. although wont go past a certain amount of revs, loss of power, check engine light, to the point that your holding up traffic. This issue has been intermittant (on and off randomly) most days it will start up and run fine (perfect).

Today the issue came up again but this time is not going away.. I checked, spark plugs, leads, MAF sensor, looked for vaccum leaks. I cant find or see anything. Until I looked around the throttle body and noticed a wire had been broken on the throttle position sensor. The TPS holding clip was very worn and hard to rewire. I managed to rewire it but problem still is there.

Would there be a chance that the loose TPS wire I found would have been causing this issue on and off when it was touching or not touching the connection? and now may have fried or killed the actual sensor itself. Needing a replacement?

any help would be very handy. This 4runner has been threw the wars as not long after I bought it I found out that it had been submerged up to the top of the dash in water, Ive already taken it to the auto electrician and had work done and its heading into the mechanic next week to get things done. but it was running good now i cant seem to get it to run good at all. Starts fine, drives, but no power what so ever.

Thanks in Advance,
91rv6
 
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What does the underside of the cap and the rotor look like?
How is the spark at each plug and the distributor wire?
How old is the fuel filter?
 
Submerged...

After 1 too much fun in muddy water, my buddy had a clogged catalytic converter on his runner. It got sluggish, until finally pushing it too hard to go on the highway he lost his engine.

Replaced the engine. Had the same problem and just about blew a second engine, then realized the Cat was clogged and was the culprit. New Cat, cleaned out exhaust pipe and it runs well again.
 
Ok update. Cheers guys for advice so far. Came back from mechanic yesterday, maf wasnt working correctly. New air filter, new fuel filter, new valve cover gaskets, but yet they still could not diagnose my "loss of power problem". The other day I noticed a broken wire on my tps on the throttle body, I rewired it as best I could. But just Incas I screwed up the wire order can someone please post a photo of there throttle position sensor wire colours going into the actual sensor? I'm pretty sure it goes brown, yellow, green & yellow, green. But if someone could confirm that for me I may have solved the issue.

Distributor is good, cap is good, spark is good. Once I get past the right wiring for the tps, if that don't fix it I'll move onto the injectors, Egr system, or the Cat. Also can someone post a picture of the cat?

Cheers guyss

This sucks having my runner running Like shoit :(
 
Did you adjust the tps after you re connected the wire? You said the check engine light was on, did you check the code?
 
It seems I have the wrong dash cluster. Sigh. It's a 4 cylinder dash where as I have a V6. Just another f**k up from the douche who sold me the car, due to this the mechanic said the codes won't read or come up on there code checker, or worse case the ecu is Water damaged.

No I didn't adjust the tps, do you unscrew it and wiggle it? Or something like that? I'm pretty over it all I love my runner and will take the time to nut it out but with working full weeks I get near to no time :/
 
Also can someone post a picture of the cat?

Cheers guyss

This sucks having my runner running Like shoit :(

If you follow the pipes for the exhaust, you should see a big can type of thing, with a senor screwed into it, and wires coming out. Probably right under the driver door side.
 

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Thanks for the pictures mate found it and checked it with the local exhaust man, the cat is fine.

Although I just picked up another runner! Time to start stripping and swapping! :) wish me luck guys cheers again for comments of help.
 
Ok. So I'm now bald. Due to the amount of hair I've ripped out with this 3vze dramas.

I'm running the standard 3vze 3lt V6, it's a 1991 4runner. Just your standard runner apart from the lift and 33's I've fitted.

I replaced - fuel filter, fuel pump, injectors, tps, mas, plugs, leads, air intake tubing, but it won't start up.

I turn the key it cranks fine, plenty of power from battery, it tries to start up but sounds like it's really struggling. If I place my foot on the accelerator it will eventually build up enough revs to start up, rev very high and then cannot hold revs and shutsdown.

Please throw me some suggestions as I have work tomorrow and this is my only vehicle, I have money to put at it but would rather save my money. Could this be a vacuum leak causing my problem or do vacuum hoses not cause such a problem?
 
A cold start basically doesn't use any of the fancy electronics and sensors, so for the most part you can just not worry about them.

That brings you to the basics of getting fuel, a spark, and air. Even a clogged exhaust shouldn't prevent it from not starting at all.

Air is easy, so look at it. You didn't mention an air filter replacement. But check that something didn't make a nest in there before the air gets to the engine.

Fuel is tougher to check. You can check that the fuel rails have pressure, or you can check that all the injectors are spitting fuel. I haven't done this on the 4runner, but had to on a V6 sports car (on that, it was starting, but stumbling once warmed up, since an air line was disconnected and so the MAF wasn't able to give the actual air info data).

Spark is pretty easy to check. Pull the plugs and make sure they look ok. Then, since it's not running, check that they are getting a spark with a tool. OTOH, if it were running, you could just pull the wires one by one to make sure the engine sounded worse (and thus it was actually doing something before being pulled).

But offhand, I'd check that fuel pressure. Maybe the fuel filter isn't full yet, or maybe something got messed up there. On that other engine, I remember replacing the fuel filter was a pain, trying to get it's banjo bolts off without breaking things, and then get them on just right so it could still have full pressure. On it, the next thing was to check the fuel pump and strainer. And bad/old gas. Those might be in your future too, since maybe that new fuel pump isn't pumping out as much pressure as it should, or there's gunk in the system.
 
Thank you guys for all the helpful information. Do appreciate it as it's led to me finding the problem! After all the checking of almost everything on the damn engine..

It seems my intake manifold gasket was missing a chunk and letting in enough air for it to not run properly. Intake removed and new gasket installed (correctly) the old 3vze is running like a dream.

Just for future reference for other users ever having running problems. My vaccum lines are up shit Creek (most of them) but this does not make bugger all difference to how the engine runs. So if your V6 3vze isn't starting or starting and stalling, or just starting rough and running rough, look at everything besides vacuum lines. Sometimes it may be vacuum but I've learnt in this lengthy experience that vacuum lines do not stop your motor from starting or running rough, might not make it run absolutely perfect but I'm sure you wouldn't tell the difference!
 
This is my girl just Incas anyones interested. Cheers again guys for the help.
 

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