SoCal4Running

Right now it could be lots of things because of the lack of history on the maintenance of the truck.

Sicking DP like noted above or gummed up throttle body causing the throttle valve to not return to the same place.

Either way its time to get in there and do some maintenance.

I do the spark plugs twice a year on my 4Runner. There cheap and it keeps the anti seize fresh so you never have to worry about stripping out the threads in the head. I use Denso K16TR-11.

Hows the timing? Does the light jump around?

Team420

also check all hoses to the vsv's... especially the brake vsv.. its supposed to idle the rig up when brakes are hit, to compensate for the change in vacuum at idle...

At any rate, sounds like a vacuum leak or problem with throttle body/tps/dashpot, etc.. as mentioned above

STRAZZE93

i found out that it was the dashpot. the boot around it is ripped and the doesant hold compression and its not springy like it should be. does anybody know where i can get a dashpot??

4Crawler

iTrader: (3)

I removed the remnants of the rubber boot on mine many years ago. Also, took some silicone spray and lubed up the plunger, pushing it in and out while still wet. Might also check the air filter and check valve underneath, they can get plugged up.

But you can probably score a used one at a junkyard:
- http://www.car-part.com/

or try:
- http://davezoffroadperformance.com/

STRAZZE93

ive sprayed mine a couple times to try to get it to spring a little better and nothing helps it. its ripped pretty bad so you can only see the spring and little parts of the boot that is still hanging on. im not sure what to do. ive also cleaned the filter. everything you press down on it with your finger it takes a while to pop back up and im guessing thats why my idle drops so much becuase the dashpot isnt holding it up like it should. i know i need a knew one. ive also played with the adjustment screw on the throttle and it hasnt helped at all.

4Crawler

iTrader: (3)

I ripped the remnants of my boot off like 10 yrs. ago. When it is ripped, it can jam up the works. Follow the FSM testing steps for the dashpot, or below:
- http://www.4crawler.com/4x4/CheapTri....shtml#Dashpot

You need the filter/check valve oriented the right way, I think it is supposed to slow the compression of the plunger but let it pop up fast.

STRAZZE93

anybody?

Stoltz23

I'm having a similar issue. Thought i would post here to se if anyone else has experianced this before i start a new topic.

88 Pickup 22RE 5 speed

Whenever the lights are on and i put it in neutral to make a turn and hit the brakes the RPM's dive bomb form around 2K to 500 or so. It only does it when the headlights are on. With headlights are off the RPM's dont drop at all.

I have not had time to investigate yet but i'm guessing its a brake booster going out? At lunch today i tried pressing the pedal and then started it. It did soften up but not like i was expecting.

mechkyle

With 3vze I had same issue, found booster hose was old and clamps didn't seal anymore. Same with vacuum lines, sometimes little metal clamps don't provide enough clamp. Although a little mickey mouse, zap straps on small vac hoses work in some applications if hose ends are still soft.

bubbageddon

Hey all, been having a similar problem, and fixed it this morning.
I just installed a 22re perfomance 2.5. It has a new throttle body as well. So, the engine is about as close to brand new as possible. When running, it idled fine after warm up, I had it set to 750 rpm. When I applied the brake however, the idle dipped to 400-500. Checked everything I could, vacuum leaks, coolant level, throttle plate closure, etc. Turns out is was my idle adjustment screw....backed out too far. Even though it idled at 750, I think that was because it was backed out past the seal. Now, even though the screw is further in, it still idles around 750. Except now it doesn't die when I hit my brakes at idle. : D

vadimidasilva

Hi, I am driving a BMW E46 318i 05/2001 1895cc 87/118 M43 engine, when you say "larger rubber hose that goes from the brake booster to the intake", are you meaning part 5 or 7 on the diagram below? Or both?)

https://www.realoem.com/bmw/enUS/sho...66#34331165518