Topic: Gnarly4X's 22RE Rebuild

[Gnarly4X]

My thoughts on the switch....

It closes at higher temp to raise the fuel pressure.

The idea being that there will be less likelihood of vapor lock with higher fuel pressure when crawling in 4wd.

Higher fuel pressure will also lower the AF ratio which also would have a cooling effect on the engine.

Then finally,   I know that an 86 came with a 1-wire O2 sensor.     So it's possible that at idle speed the engine reverts to open-loop mode and the ECU won't correct for the slightly richer mixture.   (I had an idle problem when that happened and retro-fitted a heated O2 sensor to fix the idle (which might mean this switch won't do anything on my engine because the ECU always has an O2 signal (or the ECU goes to open-loop anyway ))) 


Then if that's true, does the ECU only raise fuel pressure if you're in 4WD.......

That kinda makes sense... But...what does 4-wheel drive have to do with vapor lock?  And... what regulates fuel pump pressure?  And... where in the EFI system would the fuel pressure need to be regulated?

Gnarls.

[Gnarly4X [OP]]

Coolant temperature switches are normally "open" and close at a specific temperature -- between 200 and 240d F.  So if the coolant reaches that temperature the switch closes and sends a voltage to the ECU and that, according to the Fuel Pressure Up description, would increase the fuel pump pressure.  Exactly WHY more fuel pressure is required, I can only guess at this point.

I don't know if the 22RE is return or returnless fuel system?  If its a return system, I believe the fuel can be heated and will flow back into the gas tank... that may have something to do with the fuel pressure up requirement.

I'm just speculating...

Gnarls.

[:)bestgen4runner]

It's a return style system.
I think you might be wrong still on what the coolant temp switch does.
Look into a/c coolant temp cut switch and you might find the answers.

[emsvitil]

The fuel pressure regulator has a vacuum reference on it.

More vacuum, less fuel pressure.  (So at WOT, you get more fuel pressure)

There's a vacuum bleed off solenoid.    The ECU would trigger the bleed off solenoid.   Then the fuel pressure regulator would raise the pressure like it does at WOT (even though it's not at WOT)

With 4wd, you don't get as much airflow in the engine compartment and can get more heat buildup.

[Gnarly4X [OP]]

Is this speculation or do you have the facts?

The fuel pressure regulator has a vacuum reference on it.

More vacuum, less fuel pressure.  (So at WOT, you get more fuel pressure)

There's a vacuum bleed off solenoid.    The ECU would trigger the bleed off solenoid.   Then the fuel pressure regulator would raise the pressure like it does at WOT (even though it's not at WOT)

With 4wd, you don't get as much airflow in the engine compartment and can get more heat buildup.

I’m having trouble getting my head around this Fpu function.   Since the Fpu switch is not described or showing any tests in my 1986 FSM, it must not be a very important function??

While I do believe the switch is measuring coolant temperature...  Please explain how “With 4wd you don’t get as much airflow in the engine compartment and can more heat buildup.”?

It does appear that since the FSM indicates the Fpu is only on 4 wheel drive vehicles, there must be something that the ECU is looking for when the truck is put into 4WD?....  What is it?

Does anyone really know exactly what it does and why?

Gnarls.

[emsvitil]

Some more info:

This is about the VSV  (what I was calling the solenoid)

https://forum.ih8mud.com/threads/what-is-this-part-and-what-is-its-purpose.587302/


Still don't know the full reasoning, and why only 4wd......

[emsvitil]

even more:

http://4x4wire.com/forums/ubbthreads.php/ubb/showflat/Number/739989/site_id/1#import

[Gnarly4X [OP]]

It's a return style system.
I think you might be wrong still on what the coolant temp switch does.
Look into a/c coolant temp cut switch and you might find the answers.

Typically the switch that turns off the AC compressor is when the refrigerant gets too low, so compressor doesn't burn up.

But what does that have to do with the vehicle being in 4 wheel drive?

Gnarls.

[Gnarly4X [OP]]

even more:

http://4x4wire.com/forums/ubbthreads.php/ubb/showflat/Number/739989/site_id/1#import

I read the whole thread... Roger has contributed so much to the Toyota truck people!!  But does that thread explain the function of the Fpu switch on a 4 wheel drive vehicle?

Logically if the Fpu switch is located between thermostat and the radiator, it is looking for coolant temperature before the thermostat opens.  If it is a switch, and sending voltage back to the ECU, then the ECU is getting either no voltage or some voltage.  So what does the ECU do with no voltage or some voltage?  Increasing fuel pressure for cold starts make sense because higher fuel pressure at the injectors will atomize the fuel better and make better cold start ups.

I still don't understand what that would have to do with a 4 wheel drive vehicle?  It seems that the ECU would only know if the vehicle is in 4 wheel drive if the transfer case has been shifted.  Or does the ECU not really care when its in 4WD and there is something about a 22RE Toyota 4x4 that needs more fuel pressure??

Gnarls.

[Gnarly4X [OP]]

UPDATE:  2-16-17

I’m making some progress….

The flat orange VHT Very High Temperature paint looks good on that manifold!  I used the manifold gasket that came with engbldr's kit.  I spayed it with Permatex High Temp Copper Sealer.

Here’s what I have installed so far after getting engine dropped in and mounted…..

tranny & t-case, with fresh gear lube, both drive shafts, both shifters in,
exhaust manifold and exhaust pipe, power steering pump, A/C compressor.

Left to do or need to install (checklist to myself)

Install O2 sensor in exhaust manifold
Connected gas line to fuel filter
Connect wires to alternator
Connect starter wires
Connect ground straps
Install 3 V-belts
Install fan pulley & fan/fan clutch
Install radiator
Install 3 radiator hoses
Add water distilled water +  quart of coolant
Lube & install distributor – bolt just snug tightened
CONNECT ALL REMAINING WIRES AND CONNECTORS!!!
Install throttle body
Connect ERG tube
Connect vacuum switches
Connect throttle linkage
Tighten center motor mount nuts
Connect two connectors to tranny
Connect all vacuum hoses
Tighten harmonic balance/pulley
Adjust valve lash
Re-lube camshaft
Lube Disty Shaft tip & gear
Lube disty cam gear
Add crankcase oil (Royal Purple break-in oil)
Install Rocker Cover
Mount switches, wire holders on rocker cover
Charge battery
Install battery – leave negative lead off
Pull fuse to injectors
Remove spark plugs
Check power steering fluid
Check brake reservoir fluid
Bleed clutch slave
Connect intake tube to throttle body
Install new air filter
Install new cap & rotor
Locate disty in middle of bolt slot – light tighten
Add 5 gallons of gas to fuel tank

CHECK AND VERIFY EVERYTHING
Check everything again

Connect negative lead to battery
Turn engine over with starter while watching oil pressure.
Install new spark plugs and attach plug wires

IF THERE IS ANYTHING I LEFT OFF, PLEASE LET ME KNOW!

FIRE ENGINE!!

Check engine temperature
Check ignition timing
Inspect for any leaks
Break in camshaft per _____________
Turn off engine let cool down
Check exhaust manifold nuts
Check for leaks
Drain water and add fresh distilled water and 50% Coolant
Re-adjust valve lash

Bleed brakes

Install hood

Fire engine – check voltage at alternator
Re-check ignition timing.

Take it for a short spin!


My plan is to break in this engine, tune the crap out of it.  Drive it for about 2,000 or 3,000 miles.

By then I will have already purchased a Doug Thorley header and 2” exhaust with turbo muffler and new free-flow cat, ready to swap with existing factory exhaust manifold and exhaust.

I will tune the poop out of it.  Have it dyno’d.  Probably the next day or sooner, swap in the DT header and exhaust and have it chassis dyno’d again.

I am curious what the numbers will be with the DT header and larger exhaust.

I plan to drive it another 1,000, maybe 2,000 miles, then swap the engbldr 261 Crawler camshaft for different cam profile.  I haven’t decided on which one I want to test next.  I will tune the poop out it of the engine, install new spark plugs, cap & rotor, and then have it dyno’d again - with the new camshaft - at the same speed shop in Phoenix.

I'm curious to see what a difference, if any, in chassis dyno numbers and what my butt dyno feels. My target is best torque numbers between 2500 and 4500 RPMs, where 95% of my drive time will be.

That’s my plan.  It’s pretty much starting where my plans left off just before I totaled my 1985 22R Shortbed.

Gnarls.

[Gnarly4X [OP]]

Gear ratio calculations…

4th gear 1:1 – 31” tires, 4:10 ring & pinion – at 79 MPH  (my freeway speed) = 3511 RPMs

5th gear 0.8:1 – 31” tires, 4:10 ring & pinion – at 79 MPH (my freeway speed) = 2809 RPMs


Gear ratio calculations…

4th gear 1:1 – 31” tires, 4:56 ring & pinion – at 79 MPH  (my freeway speed) = 3905 RPMs

5th gear 0.8:1 – 31” tires, 4:56 ring & pinion – at 79 MPH (my freeway speed) = 3124 RPMs


The peak torque “sweet spot” with this engine rebuild (261C cam+DT header), according to my desktop dyno, is between 3100 to 3300 RPMs (it may be different on the street and when chassis dyno’d)  As Snowtoy pointed out, his butt dyno likes the snappy lower gear ratio.  I may end up spending the money to swap in 4:56 ring & pinions.

Gnarls.

[emsvitil]

Gear ratio calculations…

4th gear 1:1 – 31” tires, 4:10 ring & pinion – at 79 MPH  (my freeway speed) = 3862 RPMs

5th gear 0.8:1 – 31” tires, 4:10 ring & pinion – at 79 MPH (my freeway speed) = 2809 RPMs


Gear ratio calculations…

4th gear 1:1 – 31” tires, 4:56 ring & pinion – at 79 MPH  (my freeway speed) = 4396 RPMs

5th gear 0.8:1 – 31” tires, 4:56 ring & pinion – at 79 MPH (my freeway speed) = 3124 RPMs


The peak torque “sweet spot” with this engine rebuild (261C cam+DT header), according to my desktop dyno, is between 3100 to 3300 RPMs (it may be different on the street and when chassis dyno’d)  As Snowtoy pointed out, his butt dyno likes the snappy lower gear ratio.  I may end up spending the money to swap in 4:56 ring & pinions.

Gnarls.

Time for a remedial math class.....


 

3862 * .8 = 3090

4396 * .8 = 3517

3862 * 4.56 / 4.10 = 4295


Are you at least sure about the 3862 ?

 

[Gnarly4X [OP]]

Time for a remedial math class.....


 

3862 * .8 = 3090

4396 * .8 = 3517

3862 * 4.56 / 4.10 = 4295


Are you at least sure about the 3862 ?

 

Uuuuhhh.... here's what I used...

https://www.ringpinion.com/calculators/Calc_RPM.aspx

and my numbers were off???  Too early in the AM to be doing math.. but I must have plugged into the calculator a typo??

Thanks,

Gnarls.

[Gnarly4X [OP]]

Question on the gasket for the throttle body to intake.....

Do you use any sealant or gasket goop, or just go with the bare gasket?

Thanks,

Gnarls.

[Gnarly4X [OP]]

I made some good progress today.  I thought I had all the wires, connectors, and hoses accounted for, THEN I found this! It comes out of the main harness.

I don’t have any idea where it goes - IF it was connected to something.

The inside of the contacts looks like it was NOT connected to anything.

Does anyone know what this wire is for?

Thanks,

Gnarls.

[Gnarly4X [OP]]

Question on the gasket for the throttle body to intake.....

Do you use any sealant or gasket goop, or just go with the bare gasket?

Thanks,

Gnarls.

Thanks again :)bestgen4runner for your quick reply! 

Gnarls. 

[Cheesemaker]

I used the paper gasket that came with the original kit that came with my motor for the intake.


That connector on my 87 is for the temp gauge.  There is another one, that is T-shaped that goes to nothing for me. 

[emsvitil]

Question on the gasket for the throttle body to intake.....

Do you use any sealant or gasket goop, or just go with the bare gasket?

Thanks,

Gnarls.

Hylomar on paper gasket.....

[:)bestgen4runner]

I made some good progress today.  I thought I had all the wires, connectors, and hoses accounted for, THEN I found this! It comes out of the main harness.

I don’t have any idea where it goes - IF it was connected to something.

The inside of the contacts looks like it was NOT connected to anything.

Does anyone know what this wire is for?

Thanks,

Gnarls.

I took a look at mine for you tonight. I have one connector in that area that goes to nothing. It is a two pin connector. I believe the one I have is for the addition of A/C. The only one I found that has a connector like
yours goes to the temp gauge sender. The wire color is Yellow with a green stripe for the temp sensor on Mine.
Hope that helps you.

[:)bestgen4runner]

Final info that I could find on a previous subject.
If you ever see this book for sale, buy it eminently. It was given to me by a long time Chevron tech about 10 years ago when He retired. Theory and operation of 80's fuel injection systems. Knowledge that is lost forever.

[Snowtoy]

I made some good progress today.  I thought I had all the wires, connectors, and hoses accounted for, THEN I found this! It comes out of the main harness.

I don’t have any idea where it goes - IF it was connected to something.

The inside of the contacts looks like it was NOT connected to anything.

Does anyone know what this wire is for?

Thanks,

Gnarls.

It is the one of those LFRE connectors that all Toyota's have.

[emsvitil]

The 2-wire connector could be for a VSV idle up that's used with AC

[Gnarly4X [OP]]

Final info that I could find on a previous subject.
If you ever see this book for sale, buy it eminently. It was given to me by a long time Chevron tech about 10 years ago when He retired. Theory and operation of 80's fuel injection systems. Knowledge that is lost forever.

I found this book on Amazon for $12.00 this morning.  Bought IT!!  There was only ONE left.

Thanks,

Gnarls.

[Gnarly4X [OP]]

It is the one of those LFRE connectors that all Toyota's have.

LFRE...??  Left For Rebuilder's Enjoyment???

Gnarls.

[Gnarly4X [OP]]

Well, since I can't find anything to connect the bugger to, I'll just let it hang out and see what happens after I fire the engine? 

Thank you all for the "input". 

Gnarls. 

[Snowtoy]

LFRE...??  Left For Rebuilder's Enjoyment???

Gnarls.

In polite terms, yes.

[Gnarly4X [OP]]

I took a look at mine for you tonight. I have one connector in that area that goes to nothing. It is a two pin connector. I believe the one I have is for the addition of A/C. The only one I found that has a connector like
yours goes to the temp gauge sender. The wire color is Yellow with a green stripe for the temp sensor on Mine.
Hope that helps you.

Hey :)bestgen4runner!

Well... I feel like a ree-tard!!... and hate to post my guilt-ridden incompetence on a public forum..... But if I save some other dummy from doing what I did and not look really good at all the "sensors and crap" as you are re-connecting the wires in the harness, I won't feel so badly.

I bought one these because my legs were killing me bending over engine on tip toes!!

http://www.harborfreight.com/step-stool-working-platform-66911.html?ccdenc=eyJjb2RlIjoiMTE0MzcxNjEiLCJza3UiOiI2NjkxMSIsImlzIjoiMTkuOTkiLCJwcm9kdWN0X2lk%0D%0AIjoiNDQ3MCJ9%0D%0A

I woke up early this morning thinking that dang connector should be connected!   I re-read your post, re-looked at my photos (should have taken WAY more!!), and I flashed back to the other day when I was connecting the harness, and didn't remember seeing it. Must have looked all over that engine at least 3 or 4 different times!!

This morning I got on my new step tool so I could get a straight look down on the engine and there it was!! ... unconnected.... HOLY HOT CA-CA you dummy!@!!  It sits between injector #2 and #3, and if you don't look straight down on the engine, you can't see it.

Sure enough, you were right on... its a single yellow wire with a green stripe, very faded.

LFRE mystery connector solved!!

HOT TIP:  photograph all sensor locations - make list of all sensors/senders/switches on the block, intake manifold, and throttle body so when you get ready to re-connect them, you have a check off list.

Gnarls.

[Gnarly4X [OP]]

I had to cut this hose (I think its a Fuel Return Hose) off as I raised the engine from the bay as I was pulling it.  I now have to insert a duel barbed connector, insert a piece of new soft fuel hose, in order to get it connected to the 1/4" nipple on the damper connected to the injector rail.  The hose is very very hard... no doubt the original hose.  I even tried my super hot water trick to soften it, but it remained too hard to push over the nipple.

I'm not sure yet what smaller hose that attaches to the smaller nipple on the front face of the damper.

Has anyone experienced this issue?

Thanks,

Gnarls.

[emsvitil]

Fuel return hose.

The one on the diaphragm is a vacuum line.    Should connect to a VSV before manifold vacuum. (remember the discussion on the mystery 4wd thermal switch......)

[Gnarly4X [OP]]

Fuel return hose.

The one on the diaphragm is a vacuum line.    Should connect to a VSV before manifold vacuum. (remember the discussion on the mystery 4wd thermal switch......)

OK, I will check to see what hose attaches to the smaller nipple tomorrow morning.

Thank you.

Gnarls.