I've already done the timing put new spark plugs other injectors new spark plug wires new fuel filter new oil and filter and my truck is still bogging out what else you think it might be? Like when its in neutral I give it gas maybe till like 5 RPMs and it sounds like its gonna die then release it and then back to normal could it be a vacuum leak? Been trying to get my truck running good for the past 3 weeks and no success.

 

do a compression test to rule out a valve or rings. Then go from there.
Timing - cam and ignition, fuel, ignitor, air
You have to eliminate things slowly until you find it.

 

what engine and year?
Does it run like crap from a cold start, hot start? easy or hard to start?
does it get better, kind of sounds like it does, after you warm it up?
Makes me think exhaust leak or headgasket if the idle returns to normal after being warmed up after some high reving in neutral.
Any blue, black, or white smoke coming from the tailpipe?
any irregular popping or unmetered exhaust noise?

We need more info.

had you messed with anything or gone wheeling in the days/weeks before it started to run like crap? a missing connection/ground might cause something like this too.

 

Turns on perfect, when cold its a Lil high rev but when hot low rev. I know that's normal but when its hot I give it some gas from the throttle and it wants to die out completely as soon as I let go of the throttle goes back to its normal rev this only happens when I give it gas. I've was reading some forums that yes a ground cable can be the cause of this but I've checked all of them and cleaned them up, also I was reading that a TPS can also be the cause of the bogging out on working on that right now. My truck is a 1987 4runner 22re dlx on pro comp 33s. I purchased this truck like this thinking it would be an easy fix I've never even been able to go hit the trails up due to the bogging out. It has very light smoke at times but goes away. It has a cracked down pipe which on switching out in a bit.

 

Mine had similar symptoms. There was no coolant in the block.. I took off the top radiator hose and filled up the block and all was well again. Who knows if this is your problem but its just an idea! good luck

 

does the idle drop or fluctuate when you apply the brake pedal?

 

Do the FSM tests on the VAFM, TPS, and fuel pressure. Don't forget to check the air filter is clean and the VAFM airvain moves w/o sticking.

Also You might hav a typo in the first post..

 

Okay so I have already changed out my TPS, Iac valve and still bogging out. As I move the throttle slowly giving it gas everything is fine but as I get to high RPMs it Boggs out also if I give it a hard pull in the throttle it wants to give out. Could it be a exhaust leak? My down pipe is cracked right after the header and down pipe meet after the bolts could that be it? I didn't change it out last night due my son having soccer practice.

I apologize for my typo.

 

sounds to me like an intake leak or a burned valve
Take a propane torch (UNLIT) and with the motor running run the UNLIT torch around the seams of the intake manifold. If it idles up you have a leak.
Do a compression test give us the numbers of each cylinder

 

Have you pulled ECU codes yet? Could possibly give you a direction to look in.

 

An exhaust leak before the o2 sensor? That will cause it to run rich. You can do the Oxygen sensor tests, also reset the computer and it will lose it's stored/learned fuel mix.

 

I had a very similar problem with my 86. I rebuilt the motor recently and it is starting to do it again. Have you checked that you EGR is working correctly? That is the next thing i am going to look into.

 

Check all of your intake hoses. If you stomp on the gas and there is a crack in one of the hoses, it will suck in a lot of extra air causing it to bog down. My buddy's truck had a small crack in between the ribs on the hose between the intake and the air cleaner. It was doing a similar thing.

 

I have already done a ECU reset and nothing still have the same problem. I have checked all the intake arm for cracks or holes or anything having it to suck up extra air and I see nothing is wrong with it. I recently changed out my EGR valve and still having the same issue. Any help would be appreciated! Thanks for your help in advanced

 

Catalyst converter plugged?

 

Another quick thing you can look at is your fuel pressure regulator. You can pinch the return line with a pair pliers/vice grips. I thought my problem was the egr, come to find out it was a faulty fuel pressure regulator. When I pinched the return line it ran like a top.