the_supernerd

I have a 2002 3.4 engine to put in my 1997 Tacoma, which has a bad 3.4. I was told the long blocks are the same. What exactly do I have to swap over to the new engine? It looks like the exhaust manifolds will not work, but what about the intake? If I need to change it, do I have to swap the whole thing or just the upper plenum? Will I need to swap the fuel injectors?

brian2sun

I don't know if the Tacos were throttle by wire or cable still in '02, but you may need your 97 throttle body assy. You may need the '02's ECU and various sensors too. Not sure about the intake, but I think they're the same.

Red_Chili

Strip the '02 down to the long block + intake, less TPS or other electronic parts, less manifolds, and use everything from your '97 including ECM. Should have no issues.

The newer manifolds plus downpipe do breathe a bit better though.

Beto

In addition to the comments made already (throttle body may be drive by wire on the '02), the '02 ECM may expect an Air Fuel Ratio meter instead of an Oxygen sensor pre-cat. If you ever think about supercharging and getting a URD 7th, you want the AFR instead of an O2 Sensor because it provides more precise tuning when you want to richen the mixture under boost. You'd be getting into a bit more wiring to swap ECM's than just plug and play I think. Do you know what the donor vehicle is? If it's an '02 4runner then it is for sure drive by wire, with an AFR. If it's an '02 Taco, I don't know.

bain

I put a 01 engine in my 98. I just swapped the intake (for GPs) , the crossover pipe and the fly wheel because the engine came out of a automatic and mines a 5spd. Im not sure if the 02s have an electric TB or a cable. And my donor engine looked identicle to the engine that was in my truck (wires,hoses,etc)

How does your 2 engines compare?

the_supernerd

I hauled the new engine down to the truck today and compared it to the old one. They look very similar. I need to compare a little more, but the intakes look the same. The old crossover pipe looks like it will fit on the new manifolds. The biggest difference I noticed is that the new fuel injectors are red and the old ones are grey. The electrical connections appear to be the same. Are there any differences in fuel injectors or are they just a different color?

I believe the engine is out of an '02 Tacoma Prerunner double cab.

Red_Chili

The old crossover will NOT fit on the new manifolds.

If you can get the downpipe-to-cat section of exhaust from the donor vehicle, you should be able to retain the more free-flowing stainless headers and crossover.

mt_goat

X2...listen to Bill he knows his Chilies.

the_supernerd

Thanks for the information about the crossover. Does anyone know about the fuel injectors being different? I did some research, and it looks like they flow a little more than the old ones. Will my '97 computer be able to deal with that or will it be running rich without re-tuning it? I have no problem putting the old fuel injectors on it, but I want to use as much of the newer stuff as possible.

mt_goat

Bill addressed that too in post #3, the injectors are an electrical part. Can't use them unless you want to also use the 2002 ECU which opens up a whole other can of worms.

Red_Chili

Although... it does make one wonder... if the electrical connections are compatible, maybe the ECU would adapt based on the O2 readings? In theory* the older ECU should... Of course the 2002 system uses an AFR instead of an O2 and would be more precise, but that would be a pain to convert to THAT extent...

I know! You do the experiment and let us know!

*In theory, theory and reality are the same.
In reality, they are not.

Thanks for the kind words, Mt_Goat. BTW, I am in the process of installing my new, Toyota-origin, Chiliated ceramic coated crossover...

mt_goat

Pics please! Maybe you could post them here? https://www.yotatech.com/forums/f160...r-pipe-138902/

mt_goat

Are you by any chance going to supercharge it? If so, lets open a can of worms and dig in.

the_supernerd

I took another look at it today and I see that you are right about the crossover. It appears the bolt holes line up, but the angle of the manifolds is different.

I have been doing a lot of research about the fuel injectors with no solid conclusions. I agree that the computer should theoretically compensate for a small size difference. I doubt the flow rate can be much different, so I think that if the new and old both have the same electrical resistance then it should work fine. If I decide to use the new injectors then I will post back after I get it smogged.

I am not planning on supercharging it, unless you want to buy the supercharger.

Red_Chili

Done!

mt_goat

Great!