I think that could be possible... if the vafm door was not shutting all the way, wouldn't the fuel pump fire off when the ignition was turned to the run position?

 

Mine takes a few turns when it's cold (like 4-5) and she has a brand new fuel pump, fuel tank and fuel filter. lol 10 yr old plugs, cap and rotor oh and wires.. runs good though.. Those items are in my near future. still working on her..

 

but it starts right up when the weather is warm?

if so, that cranking time when cold could be the cold start valve or the aux air system.

the other thing I wonder about is the role that the fuel pressure regulator plays in this... can it bleed fuel off if something is not right? doesn't seem possible.

 

If and only IF OP's 22R-E is similar to 86-88 4Runner 22RE, there is absolutely no need to crank to build up fuel pressure..
Just put in "Start" position with clutch released and Clutch safety bypass OFF.
This will energize C.O.R. (you will hear a click hear behind glove box) and turn on Fuel Pump. Yes, even before and without airflow. See schematic for final answer

 

Mine is a 22re. Im fixing a big plate of crow. Im eating it, feathers and all.
I aplogoze for the "youre totally wrong" iit was a bad thing to say whether I was right or wrong. Im sorry.

I still swear I have heard the fuel pump energize when in run.

Forgive me for my cocky statement and for being wrong.

But I learned. Thank you for schooling me even though I resited like a crabby old man.

 

My truck is a 93 22RE it starts up with about 1.5 revolutions. Always have... Now Incan tell you that my fuel pump does not in gauge until my starter in gauges. Dunno if it's suppose to be like that but that's how it is.

 

Wow, this thread got very complicated very fast!

Mine sometimes never starts, it'll crank over 20 times... oh wait I forgot to disengage the kill switch...

 

Everybody appreciates a good sport Your sig lists an 87 22R, though?

After I disengage my kill switch, still cranks for a long time with no combustion... then I remember I needed to disengage the other kill switch. After I disengage that... still cranks but no combustion... then I remember I need to disengage the 3rd kill switch - LOL!


I haven't seen schematic for the 93 but, assuming your 22RE is wired same as first gen 4Runner, that is expected behavior. The C.O.R. which powers the fuel pump while cranking and before airflow is established only comes on when put in "start" position which also cranks the starter.

 

My problem is that on cold start ignition goes smoothly. But after some driving and when engine is warm I have some trouble. It cranks difficult and after, there is second or two very low idle. Then gets to normal. Is there some cause for that?

 

true, in theory.

however, in the real world, crank = "start" position, so you must crank to build fuel pressure... you can't get fuel pressure without cranking the motor over

unless perhaps the vafm is stuck open.

it's a stupid design, as was pointed out earlier, Honda and other manufacturers turn on the fuel pump when the key is in the "run" position.

 

And why is cranking the motor necessary to build up pressure when fuel pump is already on by putting it in "Start"? Air-flow is required? That's why C.O.R. has 2 coils (See schematic for final answer .

• Ignition switch in "Start" position powers first coil and turns C.O.R. on -with or without airflow.
• AFM contacts close and powers second coil to turn C.O.R. on when air-flow is established, even after ignition key is released

In real world, on an un-molested 22RE with a manual transmission, when you put ignition switch in "start" position, not step on clutch and not turn on Clutch Safety Cancel, starter will not crank.

However, there will be power to C.O.R. That's why you hear it click behind the glovebox. In real world, in an un-molested 22RE, once the C.O.R. clicks nothing will stop it from turning on the fuel pump and building fuel pressure- even if engine were not cranking. See schematic for final answer

 

I am really excited I got you guys so interested in this topic...anyway - yes, it takes a little bit longer to start when cold. After it's been started once - it starts very quickly.

Perhaps that supports the idea that it needs to build up fuel pressure?

 

Wow, That's allot of feedback

If you take a look at the wiring diagram that was posted earlier in the thread it looks like the COR relay feeds power to the fuel pump. If you also follow pin 4 (G) from the COR in the diagram it goes to a switch (Pin 2) in the Air Flow Meter. This switch is normally closed when the engine is off. This is used to keep the fuel pump from running when the key is on but the engine is off which is good in cases such as an accident or vehicle roll-over. In this case the key could still be "on" with the engine not running. You don't want the pump running and possibly spraying fuel creating a fire or explosion situation

Just take a look at the diagram and you'll see

If you think it's taking too long to start it could be a bad check valve as posted earlier. A bad check valve can cause longer crank times because when the fuel line has zero pressure it takes longer to build up

HighLux: Apology accepted. It's not a big deal in this case but allot of people use postings on the site to fix their rigs and plan their builds. It can get really expensive really quick depending on the info

 

good point, but people in the real world don't consciously make an effort to do that

for instance, would you like to explain that theory to your mom? lol... i'm a degreed electronics tech, but my mom doesn't know a resistor from a capacitor.

however, what you posted there could be a potential troubleshooting step, for people who are seeing these long crank times.

as in, crank for 3-5 seconds with the clutch out, then push the clutch in, while cranking, to see how quickly it starts up... if it fires right up, you might be looking at a fuel pressure/check valve issue.

xlnt job on presenting the material!

 

Yup. When I saw radrunner post, I knew I was in trouble. I can accept when Im wrong. Im not too old to be lernt by youz youngins.
It's why Im here.

 

Exactly.

Correction, though... this switch is open when engine is off = there is no airflow.

 

Correct; I used that while troubleshooting my intermittent long-cranking issue. Turned out to be just Cold Start injector connector that was not plugged in properly (from P.O.). After plugging it back in... "Tada-VROOM!" just like a Toyota should Of course, in the morning she goes, "Tada-Tada-VROOM"

Thank you, sir!

 

Seriously; A tech at work once explained to a clue-less manager that he fixed a problem by replacing the FLUX capacitor. Explanation was accepted. - LOL!

 

lol!!

he should have gotten an increase in pay!!