gummybear

Hey everyone dont want to seem like a d bag with a please help first post but this trucks got me confused.

So bought this 95 auto v6 4runner from a tech at mazda for $600 ots really clean but wont rev it dies once any throttle is applied. I know the guy i got this from he just put a head on it (cam key snapped) but once it was together did this he put new plugs wires and compression tested it all good and new fuel filter finally he said screw it and gave up so here i am lol. I went to his shop today to pick it up started it and opened up the air box to me it seemed like the afm door was way open so put my hand in front of the port and tried to rev and surprisingly it kinda did (like 1900 rpm max) so got some duct tape covered about 60% of the port and drove it home had to stay barely touching gas or rpm would fall also wouldnt rev past 2200. So I think i have a afm issue but idk maybe its something more common went to pick a part but every v6 yota truck and runner were missing afms so i dont want to spend 200 bucks at autozone on a guess anyone have any ideas all help appreciated thanks.

thook

That symptom is rather synonymous with a bad AFM or throttle sensor. But, how "way open" are you talking about? The door (measuring plate) should be entirely closed when the engine isn't running:

See pg. 234......http://personal.utulsa.edu/~nathan-b...92volumeai.pdf

gummybear

No its fully closed when off but at idle its swings probably 60-70% open

thook

Hrmmmm.....I can't honestly say how far it should open when idling. I've never looked in there when it is. Sorry.

I'd suggest, though, a dynamic sweep test with an ohm meter. Run a forum search on "AFM testing". There are threads that go over the procedure and what to look for when testing.

Also, the service manual procedure is in the link I posted.

Post if you need any more help or have more questions!

gummybear

Thanks I've been looking for specs lol

thook

Sure thing, and good luck.

gummybear

I think i left my dmm at work cracked open the afm and adjusted it manually idles good now in neutral got it to rev to 4k (kinda sluggish) and like 3k in drive but can get on the gas more i think i went a couple clicks too far ill turm it back tomorrow and test again...may even try the camry afm mod

thook

If the AFM is bad, adjusting won't fix it.

TNRabbit

Is the spring that returns the vane broken? That's what it sounds like...

bmcghie

If memory serves, there is an idle bypass channel in our 3vze AFM. In other words, that vane should be completely closed at idle, as air will pass through the other channel. I bet TNRabbit is correct, your vane return spring is toast.

The spring is very weak... you should be able to barely feel any resistance to pushing on the vane by hand. That said, there needs to be some. Once you get that fixed, I would take a close look at the TPS. For the engine to be running with that initial messed up AFM status, chances are something else isn't within spec.

Good luck!

PS Camry AFM mod might be the cheap solution for you. I believe certain years are direct plug and play. There's a writeup somewhere around here...