Hello Fellow yota fans, Long time lurker, first time poster here. I have searched the forums a bunch but could not find anything that would help my situation.

Let me give you the run down
I have a 95 4runner v6 3.0l manual 4wd. The truck has 290k on it but the engine was rebuilt around 220k. (found a receipt for an engine rebuild dated 2 months before i bought it)

Now my problem, It is currently +30 Celsius here, My truck takes about 10-20 minutes of driving before it registers the temp on the gauge.

Now this problem is not gauge exclusive, I have some throttle hesitation when cold. I will drive fine, come to a light and stop, then when i go to take off again I depress the gas peddle, and the rpms drop and you can hear the engine almost stall then it picks up and revs right up. Once warmed up vehicle is fine with no throttle problems or lack of power....

List of items that have been replaced:
Throttle body
TPS
MAF
Timing belt
the EGR has been disabled as it is broken (plugged vacuum line)
the Cold start injector is disabled as it affected my performance while driving (very sluggish and smells very rich, assume the cold start wont shut off)
Radiator
water temp sensor
ignitor coil
distrubutor
front main seal


Thats all I can think of for now. If anyone has any idea at all what it may be im open to suggestions, been working on this issue for 2 years now and Ive stumped most mechanics

 

Not in any particular order:

Are you getting any check engine light action?

The gauge taking that long to register is definitely a problem Have you checked / replaced the thermostat?

Have you checked the VAFM operation?
Have you checked the intake ducting for any leaks?
Have you checked valve adjustments?

Plugging the vacuum line to the EGR valve won't necessarily "disable" the system. If the valve is stuck partially or fully open, it can still let exhaust into the intake. This could cause issues that are more apparent when cold than when warmed up.

Cold start injector should only operate when cranking to start. If it's operating otherwise, there could be a problem with the wiring.

Which water temp sensor was replaced? You have two- one for the gauge and one for the ECU.

 

No check engine lights, not even when you turn the key on or start up. This leads me to believe it is broken

I did adjust the tps when i put it on the throttle body.
Havnt noticed any leaks and the dealership i brought it too couldnt find any vacuum leaks either.

I assume by VAFM you mean the mass air flow sensor. That was replaced with a new one, (not cheap) since I had assumed it wasnt getting the proper air flow on cold starts.

The EGR has also been welded close. We put in a piece of metal over the intake to the engine to block off any that could be bypassing if the valve was seized open.

We have looked at the wiring, nothing seems to be out of order. But there could be something hidden deep that i cant easily find. We have it unplugged for now as it seems to help. Even in the cold it starts after 3 cranks. if its plugged in 1 crank.

I replaced the water temp sensor at the back of the engine..... unless there are 2 there, as well as the coolant temp sensor going into the engine from rad. I used a 195 according to napa's suggestions.

 

Right to assume. Wrong to call it a MAF sensor. Which it is definitively not. Volume Air Flow Meter.
A what now? I've never seen one of those. Got pics?

Oh...and like he says. There are supposed to be 2 on the back of the engine(sender and sensor).

 

Sorry i ment a thermostat.... >.> too much technical jargon for me to keep up with.

Was looking at one of your other posts MudHippy, Much better then the one i used awhile back.

I had replaced the Engine Coolant Temp Sensor, I didnt replace the Cold Start Injector Time Switch, or the Engine Coolant Temp Switch for the E.F.I. Im guessing thats a good place to start.

 

We don't know what you mean if you don't know what you're talking about.

 

thanks this helped me with my problem..... oh wait it didnt.

sorry Im not a mechanic, I will try and correct my mistakes but if you could offer assistance instead of snide remarks, it would be more appreciated

 

 

Thanks for the help guys, youve all been really useless

 

Oh for crying out loud. What do you want? Money for parts? I can't afford that.

If not...then start telling me you replaced those things you were guessing were a good place to start. And that the problem didn't go away. I didn't tell you it was a bad idea...did I? And neither did he. Sooooo...

Until then...quityer bitchin'!!!

 

You said it was rebuilt recently. Not saying this is your problem but who knows what was looked at when it was rebuilt and what wasn't. If you read thru his thread you can see how expensive shotgun troubleshooting can be.

https://www.yotatech.com/forums/f116...60/index3.html