5vz NO CODES starts and idles but bogs when opening throttle
 

I had another post about this a while ago, but the post was written wrong and seems irrelevant now, so here’s the situation, and everything I’ve confirmed etc.

Also, please check the attached video to see exactly what’s happening

I have a 5vz-fe that starts up and idles, but when I open the throttle it completely bogs. This is just parked, not under load at all, so not even enough power to get it to roll. I have an OBDII reader but it’s not throwing any codes.

It was running fine, and I changed out the plugs, then went to fire it back up and it’s been this way since.

I checked all around the igniter and the wires connected to the intake but it doesn’t seem like any of them got pulled or pinched or anything.
I’ve checked all the grounds and they all seem good.
I couldn’t find any vacuum leaks.
It has spark.
It has power to the coils.
It has new plugs, wires, and coils.
Its not a plugged cat.
Year and a half ago ir so I did the injectors, fuel pump and fuel filter.
And six months or so ago I did the timing belt, water pump and valve cover.

But I think all those things are chasing the wrong tail. This started immediately after changing out the plugs, and it is super consistent. It didn’t start happening over time. It doesn’t come and go or get better or worse, so this leads me to believe that it has to be something that happened when I swapped out the plugs, like a wire pulled from the igniter or something is hooked up wrong etc. but everything is all correct, according to other threads on here anyway.

I really need some help here. I would appreciate any and all thoughts or ideas about this.

Thanks a bunch

https://youtu.be/DPeuNZo3GAM?si=5CtEH8LqStkxD07r

P.S. over the past few months it would intermittently (very slightly) bog giving it too much gas on hills, seemingly only if it had sat for a bit and then would get better as the day went on and bedriving perfect with full power. But this wasVERY subtle, and not that common, and if I kept the rpm’s in the middle range I could drive no problem and prevent it from happening at all, just a bit slower up hills. What’s happening now is 100% failure of power, so totally different. Also, it was throwing p0171 after starting to drive after the engine had been shut off, pretty much everytime, but I assume it’s just from old rusted exhaust and o2 sensors. I just reset it right away and doesn’t come back on again until I park and turn off the engine and wait and then start it and get driving down the road again, then comes back on, and I repeat, with no issues at all. None of this probably matters but I thought I should mention it since it is a somewhat related system issue, and I want y’all to have all the info possible, relevant or not.

This was recently happening to my 2003 5VZ. Replacing the Cam Position sensor ended up fixing it for me.

Ok thanks a bunch, were you getting codes for that though? Mine’s still not throwing any codes

Also, did you find out if it was the sensor itself? or if it was the pigtail wires getting pinched or something?

Also, were you able to view the video I tried to put in the posting?

Thanks a bunch!

I was not getting any codes. My truck was having this issue intermittently. Truck would start and idle just fine, but more that about 25% throttle and it would bog. The cam position sensor was scoped by the mechanic and said the amplitude output was low. New sensor and truck has been running great again. Put 3000 miles on new sensor with zero issues.
I could not see your video.

I just saw your video. That looks a little different than what was happening to mine. It could be the throttle body sensors acting up. What year is your truck ? The 2003 and 2004 had the partial throttle by wire. There are two position sensors on the throttle body that can cause these issues. Accelerator position and throttle position.

Ah ok, mine is out of a 2000 4runner, I’ll look into all these sensors, any idea of how to test them? before I dig into google searching for that haha

I took mine to a mechanic to get tested.

Problem is, the truck doesn’t drive at all right now, and I’m pretty rural at the moment 🫤

it sounds like you have miss routed a vacuum line try playing around with them a bit or find a vacuum line diagram

Thanks for the reply, I agree, it feels like a vacuum line thing, but I only had to unplug two vacuum lines to remove the intake, and I’ve double checked those, and then sprayed starting fluid around as well to look for leaks somewhere but all seems to be good woth the vacuum lines 🤷