Hard to start when warm

[Jukelemon]

Well, the Water Temp Sensor did not do the trick AND I have tried the fuel pump trick-jumpering the Fp/B+ terminals as well. I am getting a bit baffled at this.

Here is the issue:

Starts great cold and great right after you sut down BUT will not start right away after it has sat for a bit i.e. engine still warm but not hot/cold.

Any ideas?

 

[KliersLC]

You have the 22re Right? Probly doesn't apply, but my 22r had that problem and it ended up being a crack(ormaybe a bad seal) in the carb that allowed fuel to drain out and flood the engine when it was warm. It finally caught up with me when it ran through an open intake valve and pooled in the cylinder. When I started it, all that raw fuel got blown out the exhaust port, where it was promptly ignited by the next exhaust stroke. This caused a fireball to travel down my tailpipe until it got backed up at the muffler and ripped it open like a can of sardines. I had only been back from Iraq for two months and I thought that I had been car bombed......



But, like I said, if you have the RE then that probly isn't yer problem, although a leaky injector could cause similar problems.(WAG)

Other than that I don't know. Does it seem flooded out or starving? IIRC you just did a tuneup, did it do this before the tuneup or only after? Did you fiddle with the timing?

Anyway, good luck and keep us posted,
Dan

 

[Jukelemon]

22re here. It did this prior to the tuneup. It seems like it is starving and that is why I did the fuel pump patch so that then fuel pump comes on when you turn the key not when you crank the engine i.e. initiates the control relay which initiates the fuel pump. That did not help. So I know there is fuel delivery. Could be a leak but I do not smell a rich mixture in the exhaust.

Really not sure at this polint. More irritating than anything because it takes two starts everytime it is in warm condition.

 

[Bear80]

Well 1 out of 3 of our 22re's has that exact problem. Dad's '87 4runner cranks right up, my '86 has the heat soak problem slightly, and then my dad's '86 has the problem as bad as you. Dad's been chasing the problem for years and we cannot figure out what it is that could be different between the 3 enignes.

Check your cold start injector sensor, unless that is what you are calling the water temp sensor since they are side by side. The problem seems to be that the comptuer "thinks" the engine has been run and is up to temp, however it is not. I know Toyota updated the sensor, make sure you try that path first. The only other possiblity is that you might have a slight fuel leak, just enough to lose vapor. If you solve the problem please tell us! Good luck!

I'll add that all 3 engines have been rebuilt/new and senors changed etc to no avail.

 

[Jukelemon]

I believe you are referring to the air temp sensor-that is right beside the Water Temp Sensor-which really should be called a Coolant Temp Sensor.

That sensor, according to the FSM, is not part of the diagnostic tree-which means very little of course but nevertheless is a fact according to Toyota.

It is very odd.

Thanks for the update

 

[Bear80]

Nope, there is two sensors above the air temp sensor which is actually called the idle air valve. One is the water temp sensor for the computer, the other is for the cold start injector timmer.

 

[Jukelemon]

OK, I got you now. The FSM does not mention that sensor on its diagnostic tree for hard warm starts. So, you are saying that the Cold Start Injector sensor is the sensor to the right of the Water Temp sensor?

Thanks bear

 

[Bear80]

I'm doing this from memory and I'll check later when I get home but yes the smaller sensor (I think they are the same wrench size) to the right is the cold start timer. Also I cannot recall if it was the water temp sensor or the cold start timmer that Toyota updated years back for hot climates.