Rav4 3sfe to 5sfe engine swap Options

[ricochet1490]

So, I bought my first Rav4 about a month or 2 ago. I've been in the celica world for a long time and I wanted a winter beater. As it turns out, the 3s decided that it was going to start Rod knocking like a beast. Needless to say, car needed work.

I had an old 5s just sitting on a pallet in the garage collecting dust. it came from a 94 celica, and it ran when it was pulled.

Now that I've got everything out of the Rav, and from what i'm told, the 5s block will need ground on the back to make space for the transfer case, but otherwise it should be pretty straight forward I think.

I haven't had time to research everything... but to be honest there isn't much out there on this particular swap because there aren't that many gains to be had. For me the gains are purely $$$.

if you guys see anything glaring, PM me and let me know if you would....

The Plan
1) swap wiring harness from 3sfe to 5sfe
2) "depending on how the ecu works out", swap over exhaust manifold because of OBD1/OBD2 differences in the model years
3) hook tranny and T-case to 5sfe ( grind block as needed, additionally brace as needed for missing mounting points)
4) repair subframe rust, mount engine and tranny to subframe - reinstall in car
5)hook everything back up including 3sfe ecu to run engine. ** Pray ecu can deal with extra stroke/air and change fuel delivery to accomodate**
6) ** pray that i don't need to swap injectors to do this to get engine to running** - Does anyone know if there is much in the way of difference between the injectors? basically I'm looking to run the 5sfe like a stroked 3sfe. Should work I'd think.

[Bitter]

just run the 5S with it's injectors on the 3S computer I'd imagine? It'll be interesting to see this completed, a 3S-GTE Rav4 would be cooler but $$$ is king.

[Batman722]

The 94 5s doesn't have cam and crank sensor the 3s ecu will be looking for.

[Bitter]

I didn't catch that. Good point! He might need to get the front bits off an OBD2 5S to make this work, I doubt the 3S parts will swap.

[ricochet1490]

@batman - I appear to have located at least the crank sensor part of this as an issue. I'll illustrate in the below pics. may have to try and run the 5s ecu..... Do the later 5s's have the cam and crank sensor?

In any case - here we are. Wiring harness is swapped over mostly sucessfully.

Issue #1 - AC compressor plugs are different. Maybe can swap over 3s compressor? Don't know yet, need to investigate.


Issue #2 - Random plug available, not used on 5s, used on 3sfe. - This is likely the aforementioned Crank sensor


The wiring on the other side of that for the 3sfe goes down beside the crank pulley. this COULD be a major issue. We'll see.


There are some other harness length differences, but everything does plug up, it's just a little more stretched than it was before.

If I have to use the 5s ecu, I wonder how that would affect the transmission part of this car given that it's an automatic and I think the ECU has a hand in controlling that mess.

All unknowns, nothing unsolvable I don't think though. Curious that the 3sfe would have a crank and cam position sensor however.... unexpected.

This post has been edited by ricochet1490: Jan 3, 2016 - 10:24 PM

[ricochet1490]

http://www.rav4world.com/forums/85-4-1-fau...s-98-3s-fe.html

1997 3sfe doesn't have the cam position sensor, it has a dizzy, so at least that part is taken care of.

The sensor behind the crank pulley is still an unknown

[mkernz22]

Is the crank sensor on the block or the oil pump assembly? Cause if it's the oil pump assembly, you could purchase a 96+ Celica one for the 5sfe or swap the 3sfe one over.

This post has been edited by mkernz22: Jan 13, 2016 - 9:18 PM

[ricochet1490]

Is the crank sensor on the block or the oil pump assembly? Cause if it's the oil pump assembly, you could purchase a 96+ Celica one for the 5sfe or swap the 3sfe one over.

I think it goes through the block and into the case.... not a show stopper, I'm sure its just a hole with an o-ring or something simple.....

What I don't know is what the trigger mechanism is for it. It appears that the 96+ 5sfe's have a similar sensor. local guy selling a 5s froma 97-01 camry sent me a picture and it's there on that block.... but he wants 800 for the used engine as is. The point of doing this was to save myself the $$ and use this motor I ALREADY had. so idk

if anyone has any other ideas about how to send that crank signal that might be quick and dirty I'm all ears. Otherwise im dropping the oil pan to see what this sensor and trigger for it looks like. if it's pressed on the crankshaft I'm going to be pissed because I REALLY don't want to tear this motor down for that.

[mkernz22]

Is the crank sensor on the block or the oil pump assembly? Cause if it's the oil pump assembly, you could purchase a 96+ Celica one for the 5sfe or swap the 3sfe one over.

I think it goes through the block and into the case.... not a show stopper, I'm sure its just a hole with an o-ring or something simple.....

What I don't know is what the trigger mechanism is for it. It appears that the 96+ 5sfe's have a similar sensor. local guy selling a 5s froma 97-01 camry sent me a picture and it's there on that block.... but he wants 800 for the used engine as is. The point of doing this was to save myself the $$ and use this motor I ALREADY had. so idk

if anyone has any other ideas about how to send that crank signal that might be quick and dirty I'm all ears. Otherwise im dropping the oil pan to see what this sensor and trigger for it looks like. if it's pressed on the crankshaft I'm going to be pissed because I REALLY don't want to tear this motor down for that.

I think it's actually on the oil pump assembly.
The part numbers are different between the two years.

And pictures to confirm.
You can see the slot cutout for it on the '96+ picture.

1995<below (Part #: 15100-74060)


1996+ (Part #: 15100-74050)


And you can swap it over from the Rav4 since the part number is used for both vehicles.
http://toyotaparts.bochtoyotasouth.com/toy...t_name=oil-pump

So there you are, saved you a huge head ache. That'll be $200

And when you take it off, you have to take off the oil pan because there are two nuts on the inside that go to the oil pickup. Don't try to just pry it off cause it won't come off. Ask me how I know.


This post has been edited by mkernz22: Jan 14, 2016 - 5:00 PM

[ricochet1490]

Haha thanks Mike. I'll be looking into this directly.
What's the trigger for the sensor? Any idea?

[mkernz22]

Haha thanks Mike. I'll be looking into this directly.
What's the trigger for the sensor? Any idea?

That I couldn't tell you, you'll just have to compare the gear or crank on either engine. Hopefully it's the gear, cause I know the gear slides all the way on there and the crank doesn't show.

[mkernz22]

Any update?

[block]

This better be worth it lol

[ricochet1490]

I was in Europe last week. So no update.

I'll be working on it Saturday all day for sure so hopefully we have something by then.

Everything to this point has been a cake walk, and I haven't done much more work that pull a motor to this point (yeah I swapped an engine wiring harness over but that's nothing really big)

If this was a 96+ 5sfe, it would have been done already because of the crank position sensor issue.
Once I resolve that Im just praying that the 3sfe ecu can run the 5s by trimming the fuel adequately based on feedback from the O2 sensors.
If I get to that point and fail then, that's when I'll be pissed haha

[ricochet1490]

So I've got everything sorted I think. As you can see here, the crank position sensor runs off the timing sprocket with the sensor integrated into the oil pump. Everything else had already swapped over and plugged up.


So, tonight with any luck I'll have the obd1 5s oil pump removed, the one from the 3sfe swapped in, and the oil pan back on. After that I'll swap over the AC and begin trying to mount the 5s to the awd gear box, grinding the block where I need to to make it fit. Then a swap of exhaust manifold somewhere there to make sure I get that oxygen sensor... I think it'll work.

The only thing that'll stop me now is if the 3sfe ecu doesn't have enough fuel map to run the 5s because of the extra stroke. But I'd sure hope it would. We'll see what happens I guess.

[Bitter]

SAFC can fix that?

[ricochet1490]

SAFC can fix that?

Good chance of it. Nice idea.

If it wasn't automatic I'd run the 5s ecu..... stupid transmission control.

[mkernz22]

SAFC can fix that?

Good chance of it. Nice idea.

If it wasn't automatic I'd run the 5s ecu..... stupid transmission control.

I think I might have an auto 5s ECU somewhere. I had one parts car that was 96+ that was auto.
If someone can get me a part number for the ECU, then I'd try to dig for it in my shed come the warmer weather.

[Bitter]

I still think the 3S maps with 5S injectors will work close enough, it won't know it's bigger injectors so it'll run the same maps and duty cycles and probably be close enough. It's a Toyota, not rocket science.

[ricochet1490]

Successful weekend.
Engine bolted onto the transmission. Had to grind the back of the block down probably 3/4" where the two stud holes are to clearance the differential. Odds and ends to tie up now and hopefully back in the car soon.

This post has been edited by ricochet1490: Mar 21, 2016 - 11:13 AM

[ricochet1490]

Ok,
So I need some help.

So it's not driving yet. turns out it hasn't been quick and simple to solve this fueling issue... And I could really use the help because it's otherwise done.
So the current fuel systems is the 1994 5sfe fuel rail and injectors, modified with the fuel pressure regulator removed off the end of the rail and replaced with the "cap" that came from the injector rail off of the old 3sfe. I did this because the regulator on the Rav is in the tank. I assumed this would be good enough as I have started and ran the car. The issue is that the car doesn't stay running for very long, like maybe 15 to 30 seconds and it shuts off.

So in trying to solve this issue, I have come up with a couple theories and have done some research. This guy had a similar problem, but never got any answers. http://www.rav4world.com/forums/85-4-1-fau...ifferences.html
But the issue is similar.

The 5s has the 23250-74100 injector


The 3s came with the 74140 injector (Could either be because of Cali emissions or the Returnless Fuel System)


On the bench


So my theories of operation are this, keeping in mind that it does run, but very shortly. When it dies it will not restart for several days really. You cant get it restarted in the same day (why I think it's fueling)

1) the 74100 injectors don't like the fuel system being set up that way as a returnless (although you would think fuel pressure should be fuel pressure) The solution here would be to make the system a return style system with the old FPR installed back on the rail running a new line to the tank. Of course removing the FPR that is currently in the tank.

2) The 74100 injectors don't like the electrical signal being given to them by the ECU (maybe a high vs low impedence thing) and will run for a moment, but not enough to sustain. Maybe there is some sort of resistor that could be soldered in? Both injectors measure the same 14.3 Ohm's of resistance however.

3) It runs for a minute and dies out because of a bad Oxygen sensor in the exhaust header. There was a bad sensor in that header that I never got replaced before the 3s crapped out. If it is sending wrong or mixed signals this could be the issue. But again, why doesn't resetting the ECU fix that issue and give me another 30 seconds of running? I don't know which sensor it is, but could figure it out or just change them both.

Are there any theories?

[Bitter]

30 or so cc won't make it not run, they're the same impedance, check fuel pressure.

[ricochet1490]

You thinking too much or too little?

[Bitter]

Could be either, should be around 40-50 PSI to have a running car. A little more or less than spec will still let it idle.

[ricochet1490]

Could be either, should be around 40-50 PSI to have a running car. A little more or less than spec will still let it idle.

Yeah that's what I figured too. It was a running and driving 3sfe when it was pulled. So I have to assume fuel pump/regulator have to be good enough. ****ty part is there isn't a fuel pressure gauge at my local parts store that fits imports. So it'll be a few days before I can confirm.

[njccmd2002]

why not get aftermarket fuel regulator. there are cheap prices out there to be had. even a used one.

If you are worried about an in tank regulator, check smaays v6 thread, he built and in tank pressure regulator. go back to the basics, reinstall the injectors the way it needs to be and do the in tank regulator.... if this does not work, have you tried a new ecu,

maybe ecu overheats, and then shuts, off. seen to many ecus react that way.... Triy to get a spare ECU


http://www.6gc.net/forums/index.php?showtopic=92362



that is smaays pic

[JasonTX]

i'm a little confused on the ac and injector issues? .maybe i missed something but could you not just swap oilpumps and use the 3s manifolds, fuel rail and ac compressor?

[ricochet1490]

Update.
Fuel pressure and spark timing check out. Fuel pressure holding at a constant 50psi.

Jason to answer your question, almost. The AC compressor had different plugs. And because I'm using the 3s wiring harness, I needed to swap compressor. Changed the oil pump fine. Changed the exhaust manifold fine. In hind sight I should have changed the intake manifold as well. Would have made things easier. But the injectors aren't compatible with the 5s head. So I would have had to keep those anyway.

Plugs are getting coated with fuel. Dry plugs in, no fire.

There is spark because my timing light is flashing, but maybe it isn't strong enough?
My passing theory now is that 4 months of the engine being out have meant an exposed fuel system where maybe the ethanol has attracted water and has fallen out of solution.

[Bitter]

Check compression I guess. And check spark AT the plug lead, not just the inductive pickup on the timing light.

[ricochet1490]

OK, so it now kind of runs, but still dies. I put straight fuel injector cleaner in the fuel line after the fuel filter and it is now restarting in the same day with some time between start attempts, but only barely idles and doesn't rev hardly. I do have a crank position sensor check engine light, but don't know why that would make it choke and die. It'll "idle" longer if I have my foot to the floor, but that's about it.

I'm right now thinking that either the injectors aren't working right with respect to fuel atomization, or they are flat not going to work because they might be spraying too much fuel. Perhaps the 5s injectors are totally different than the 3s injectors?

definitely getting closer.

[njccmd2002]

crank sensor light? i would check into that. make sure no short in wires, or sensor good

[ricochet1490]

So I think it has something to do with injector wiring and firing of said injectors. again, I have 3s wiring and ecu, with 5s components. I find it interesting that there seems to be all injectors on the 5s wired to both pin 12 and 25? There are bridged terminals right at the pin. Maybe I'm reading that wrong, but I don't know what to do about this now.

for anyone curious..
3sfe injector wiring using 11,12,24,25


5sfe injector wiring using only pin 12 and 25


This post has been edited by ricochet1490: Aug 19, 2016 - 6:55 PM

[Bitter]

Both look like batch fire in pairs?

[ricochet1490]

well, you just gave me something to look up. the 3s ecu is trying to fire it sequentially, 11,12,24,25, 1 pin for each injector. The 5s ecu was firing in batch, all 4 fired off of 12 and all 4 fired off of 25.

this probably is coming down now to a fuel quantity issue based on the quantity of pulses.

This is going to take some thought i think. if the injector volumes are different, then simply just splicing each injector into each output isn't the answer. I wonder if I could piggy back the 5s ecu to handle the fueling, ignition etc, and the 3s ecu to handle the rest of the car functions like tranny, gauges etc.

[ricochet1490]

The more I've researched today it shouldn't really matter if it's sequential or batch fire if the quantity of fuel is the same. and this is where it gets weird.
Everything here says not enough fuel.
Larger engine 2.0 -> 2.2L, so 50cc additional air volume per cylinder
Smaller injectors, computer is set to run a pulse width for a 250cc injector, the 5s injectors are 220cc. when you do the relationship simple math of injector size vs displacement and assuming the same pulse width, I need 20% more fuel than what I'm getting today to make stoich.

But when I pull the plugs, they are coated black and smell of fuel because it's not firing and when it does run the tail pipe smells rich.

so which is it? perhaps not enough fuel to allow combustion, that eventually just builds up and causes the plugs to foul?

[Bitter]

when you get it running try to spray some carb spray into the air intake, if it smooths out a little then it is lean, if it stalls it then it's rich.

[Pez]

I was just a passer by, reading your thread. I worked in a shop specializing in toyotas and lexus for 4 years and worked on a lot of these engines. If the car runs and simply dies with no struggle (ex. no shaking, stuttering, choking) after a short time of running then i can almost gaurentee that its crank position sensor related. Check to make sure you have RPM on the tach while its running, no RPM = no crank signal, the computer runs initially off open loop where it doesn't look for crank signal, but after a short period of time it switches to closed loop and cannot run without crank signal. The check engine light for CKP confirms this. There is no need to change injectors, fuel pump, spark plugs, those things would have very diffrent symptoms. Check your wiring, your connections, and ecu pinout in relation to your CKP and i think you will find your issue. Most cars do not run long or even start with CKP problems. Best of Luck, jeff

This post has been edited by Pez: Aug 23, 2016 - 12:55 PM

[njccmd2002]

^^ posted the crank sensor idea 5 posts ago, he did not listen. lol... but maybe he checked it already

[ricochet1490]

Well, it runs and drives!

As it turns out, it really is that easy. The 5s will run on the 3s wiring and ECU.

None of the things that we were talking about ended up being an issue. The issue was that the engine had skipped time when I first started it up after I installed it and I didn't know it.
Compression test yielded a 50psi result and when inspected the belt was about 4 teeth off. The tensioner spring was weak and couldn't keep tension on the belt. Now that we have a new spring installed and the timing issue resolved it purrs like a kitten.

I have a vacuum leak somewhere, it's idling a little high. But a trip around the neighborhood and all is well.

thank-you to everyone who provided insight and information!

[Bitter]

Haha wow, I thought I said timing a while back?