That's what *I* thought, can't reason why there would be any issue, aside from R134a vs R12. Guess we'll wait for wellyman to weigh in.

I think the "A/C problem" is that other's tried to use the 3.4L compressor.....which is for the newer type refrigerant. I think that resulted in leaks and not so cool A/C. The 3.0 and 3.4 compressors look almost the same on the outside. The only difference I noticed was in the valve body and the pully. The simplest thing for me was to switch the pully's and that appears to have solved the problem.

I read about one guy who switched the valve body's and another who had custom hoses made to retro-fit the newer compressor (the connectors are different on the two systems). I think this was done to try and convert to the new refrigerant.

Trying to switch to the newer refrigerant might save a little cash when recharging tte system. But, from what I hear it doesn't work all that well. My solution was to keep the older system and pay the extra cash to have it recharged.

Hey all:

I really must say I appreciate everyone's involvement. I'm happy that I have so much new info when I finally get a chance to check this thread. Again, thank you all. For the life of me, I still can't get the ECU to communicate with the OBD scanner. I've looked, and the signal wire is in pin 7, not 2. I've also tried 2, but still nothing. There is something interesting, however. My MIL doesn't come on. I'm happy with that and right now I'm ASSUMING my engine is now running right. When I try to pull codes, the scanner still says "Link failed, try again?" I can't get it to connect, but trying this sets off the MIL. I've just been pulling my EFI fuse to reset the MIL. So, by this, I'm again assuming that there is continuity amoung the signal wire. I know the three other wires, the 1 pos. and 2 grounds, are correct as the ECU is powered via the port. Gonna mess around with this some more, and guess I'm gonna call Mike C at ORS to discuss. Thanks for the name. I've done my fair share of ORS ordering, and I must say, I've found them very helpful and it's nice to find companies that still care.

The A/C issue, as I've read, is in the circuitry. The wiring diagrams don't exactly match up. The 5VZ uses an "Integration Control and Panel" control, and the 3VZ uses an "A/C Amplifier". That's the jist of it, and I really haven't dove into it yet. I've just heard that the A/C doesn't work with the swap. I don't have the 5VZ control, so I'm really just asking you all if there's issues, and if anyone can confirm a WORKING A/C. I can get more specific if anyone is willing or interested in the EWDs.

93CORUNNER:
I did the same thing as you did on the compressor. I put the 3.4 pulley onto my R12 compressor. Easy as pie, and I didn't have to drain my R12 during the swap. Actually wondered why you had to. I've got a pig of R12, that will last my 4Runner and 88 'stang their lifetime. Ever in the St. Louis area? I'll give you a free fillup.

Still working on CC, which is another that has discrepancies in the EWDs. So if anyone wants to chime in on if they've got it to work or not, that would be very helpful.

Also was wondering on the P/S pressure sensor, that's on the 3.4 EH. I'm assuming that it plugs into the newer rack and pinion steering on the newer stuff. I just have this unplugged, as I can't find anywhere that it's supposed to connect to. I've checked all over the pump, and couldn't find any sensor, so I'm assuming it's not used on Gen II's.

I'm still working on this thing quite a bit, so this is where I am now. Thanks again for everyone's help.

Oh, and about the fuel pump. I'm still having occasional issues with stumbling and surging. I suspect the fp, and I want to replace it as a diagnostic. I just want help with selecting one. If you had to buy a NEW fp for your GEN 2 with the 3.4L swap, what fp would you buy? What will fit in addition to the 93 4runner? Aftermarket, or one spected for the 2K Tundra 3.4L? I figure while I'm buying a new one, which one would be best for performance and worth an upgrade as such. I'm really worried about this, as I suspect either VERY NOISY injectors, or knocking. I don't want to hurt the motor, and not being about to connect to the ECU for codes makes my uneasy driving it. Anyone's 3.4L have loud injectors under load?

I drained my system out of stupidity.....I just kind of assumed I was gonna have to take the compressor off to pull the 3.0L motor....figured it would be in the way. Really wish I hadn't...it would have been easy to unbolt it and just tie it to the frame rail.

On my setup, there were two wires that were involved in the A/C. One went to the ECU and the other was the clutch wire on the compressor. The clutch wire is a no-brainer. The ECU wire was a bit of a hassles to figure out. I have this memory of there being two A/C wire pins on the 3.4L ECU and only one from the body. I eventually figured it out by reading some circuit descriptions I had in the factory manual I got for the 3.4L. It wasn't in the wire diagrams....it was in some other section of the manual I dowloaded from the website I got my factory manuals from.....was a whole set of circuit descriptions saying what everything did and how it did it.

Like I said, I'm not positive my A/C works...but all indications are that it will.....we'll know when I have the system recharged this coming spring. otherwise it's back to the wire diagrams and manuals.

My wife's 1997 3.4 only pings with cheap regular. Decent regular or midgrade, no ping. It could be carbon buildup, it could be spark plugs (my 3.4 on the stand had AC Delco spark plugs, single ground, instead of the proper ND plugs <img src="/forums/images/graemlins/shame.gif" alt="" />), it could be low fp, it could be cheap gas. It couldn't hurt to just pick up a fuel pump for your year at the boneyard and swap. Couldn't hurt to put a fuel pressure gauge somewhere, even under the hood, either! Quick way to rule it out. Fresh fuel filter? You might just try to put in some mid or premium fuel in the short run.

I run 89 in the motor, and I've tried 93 to see if there's any less pinging, if it's indeed pinging. I don't hear a difference, but I have horrible hearing so I can't rule it out. But I would have to say that octane doesn't influence the noise. I want a new pump for it. I just don't know what my options are as far as a replacement. I'm sure OEM is outrageously priced. I just don't know what will fit, what will work best. I don't know if I buy some aftermarket performance pump if it will push too much fuel and hurt my FPR or the pump. I just want a NEW, sufficient pump. I'm not going to go thru the effort of checking the pump, checking the sock, dropping the tank without replacing the pump anyways. So, I'd really like to order a pump here ASAP. The filter is new. The motor only has 30 or so thousand miles on it, so the pinging/or noisy injectors is concerning me.

My CC works fine, so it's just the A/C, the FP, and the connectivity with the ECU as my remaining issues. Not too bad for a first timer.

Father Caskey once told me: Blessed are those that get their engine and ECU from the same donor truck.

LOL! I have a call into him now. Still waiting for a reply. Not really any new news from here. I got side tracked today with my rear window motor finally going ka-put. I had it apart about a year ago, but today it was totally f**ked. When I took it apart today, I knew I couldn't fix it again. So after pricing them and checking their availability, I checked on aftermarket. $102 and $45 core was the best I could find. I'm putting a manual crank on it. I don't mind crawling in the back....

They are swamped so it may take a while to return the call right now. By the way, sure its the motor? The most vulnerable parts of the rear window stuff are the various switches and wiring harness. Roger Brown has some troubleshooting info on his site IIRC.