i hate to make a post with this topic, since i know it's been covered a couple of times. but my 3vz has recently started idling weird, well not idling at all really...if i let off the gas then it'll just kinda sputter around 500rpms for about 2 seconds, then it'll almost die, race back up to about 900 or 1000rpms, then down to like 250, then back up to 1000, then it'll die.

i was thinking maybe fuel, but that would make it just die, not sputter like that.

i haven't checked anything yet really...gonna do a compression check out of curiosity, then fuel pressure check out of curiosity, check my timing, and i'd like to check for vacuum leaks as well....idk what else though.

my check engine light has NEVER came on, so i might check my codes just out of curiosity.

anyone has any suggestions on something to check i'm open to any and all help, need it fixed ASAP so i can get back to work.

 

okay so i replaced my positive battery terminal was shot, so i replaced that just cuz..

replaced my fuel filter.

and then i fired it up, ran rough for a second then fine.

then after it got 100% warmed up...it started idling a little funny AGAIN...kinda dropping down and surging a little.


well i just HAPPENED to lift up on the end of my intake (i have a K&N, i took the filter off before i did this) and the idle was GREAT after that!!! let the intake back down and it ran rough again, lifted it up (like 1/4" or 1/2") and it ran great....whenever i lift up on it basically make the AFM level. whenever i let it down, it slopes down quite a bit....i was thinking maybe this little bit of being un-level might be causing the "door" inside the intake to maybe be too closed or too open.

well as all of this was going down, i turned the truck off and unplugged the AFM (didn't take the cable off the battery) fiddled with the bracket holding the intake up, went and started my truck and it ran great then started running like crap and died....noticed i didn't plug my AFM back up, so then plug it back up and tried to start the truck but it would fire right up and then die immediately. took the positive cable off the battery for about 15 seconds or so, put it back on..and the same thing happens.


so what the hell is going on now!?!??!

 

Bump to the top! anyone?

 

You said you repaced your positive side terminal, how about the wire/cable? Mine was doing similar things, had to replace my entire cable from battery to starter

 

Nevermind

 

Could be a vaccum leak. I had idle surging problems and when the vaccum tubes where fixed it seemed to cure the problem.

 

I'd say vacuum also, but he mentions that the truck runs fine till warm. I agree it sounds like vacuum.

Spray some starter fluid around the vac lines and see if you get the idle to rev up a bit, then you know you have a leak.

 

believe i found the problem, couldn't see it at night because of not having enough light, and not paying attention..

the rubber part of my K&N intake (closest to the throttle body) has a massive crack in the bottom....that would make it not run since the motor is getting whole lots of Un-metered air.

so i'm gonna see if i can bum a piece of intake off of another vehicle in the local yard and fix this dude so i can get to work on my new boat lol