phaze1

iTrader: (4)

I have a 99 GLE Auto (cali spec) that has been swapped to a 5 speed manual, the motor was swapped along with it. Not sure what the motor and trans are from (the VIN on the trans says its from a 97, not sure what trim). The check engine light is on and the wire harness is all hacked up. I have decided to eliminate the check engine light by replacing the ECU with a manual one. The harness is all spliced up, so I will replace that also. Now, does anyone know if all this will work properly? Will an ECU from a 99 SE fed spec manual trans, work with a 99 GLE cali spec that has a 97 motor and trans from a fed spec SE or GXE? Also will the engine wire harness off a 99 fed spec SE 5 speed work with a 97 motor and trans from a fed spec GXE or SE? I know its a little confusing but, a lot of you guys know more than mechanics at Nissan dealerships. Thank you all!!!

KRRZ350

iTrader: (29)

I wouldn't worry too much about the wiring harness, it probably: 1, has a bunch of extra/cut connectors for the auto trans 2: was spliced into for the reverse lights and starting system. 3, might have had '99 style connectors spliced off of it to attach to the identical '97 stuff that uses different connectors. Swapping the wiring harness is alot of work, allthough so isn't the ecu, that thing is a royal pita!! Once you finally get a manual ecu, normally that would leave you with only one cel for the r/n switch, and I was the one that finally figured out how to fix that so pm me or bump this when the time comes and I'll steer you in the right direction, another .orger actually did it and found a shortcut for the wiring.

Now, if you have a '99 cali spec but a '97 engine.......... You have swirl valve code/s, and depending on what exhaust you used you might have o2 codes as well and would need some o2 sims, research fed-spec conversion or header install in the 5th gen forum.

On to the ecu................. If you are '99, you must use a '99 ecu, several pin locations are different, you must also match cali or non cali spec due to the o2 sensors and swirl valves and what not, not sure if you could just use a '99 fed spec ecu in your case and kill two birds with one stone, allthough you would still need to add an extra bung in your echaust behind your main cat, again i don't know maybe the didn't swap in the 97 rear manifold and y-pipe. can someone else chime in on whether this is possible?

Also, a full list of codes would be helpful, autozone does it for free, have a pen handy as well as info about what y-pipe/manifold combination was used with the engine swap. And thanks for the compliment about us knowing more than dealer techs....... sometimes anyways.

phaze1

iTrader: (4)

Thanks for the reply!
I just wanted to replace the harness also because the MAF code was on and after replacing the MAF and resetting the ECU it still came back on. So I figured, since I already found and ECU and harness that hasnt been tainted, I might as well replace since I dont know if the splicing is bad or the actual units are bad. Do you think the fact that my car was originally cali spec even matters at this point since the motor is now a 97 fed spec? I mean what difference does the cali spec have over the fed? Its all motor related right? So in that case, I guess replacing with a fed spec ECU would be a good choice since the motor is fed and now it can understand whats going on. As far as the chassis controls go.....windows/doorlocks/sunroof/gauges/warning lights/etc.......would the SE model ECU affect any of those controls on my GLE model? Should they match up and work properly? Also, are the wire connectors on the 97 motor the same as the connectors on the 99 harness? Thanks buddy.

KRRZ350

iTrader: (29)

Some of the harness connectors are different iirc, not sure which ones. Yes, the ecu's are different for a cali spec, cali spec 99's have an extra o2 sensor, swirl valves, both of which are contolled/read by the ecu, and maybe some other stuff is different, not sure.

Your 'motor' might still be somewhat cali-spec still at this point, depending on what was used for exhaust, allthough they more than likely used the '97 rear manifold and y-pipe. A full code list would be helpful, directions to check them yourself are in the stickies.

Also, even if you swap wiring harness, you will still have to spend some time in the Factory Service Manual. You can download it from VQ35DE.com

phaze1

iTrader: (4)

Ok, so it sounds like as long as I have the orginal exhaust manifolds/O2 sensors/intake manifold off the 97 fed spec engine, I should have no problem using the 99 fed spec ECU. Makes sense. Now what about using a 99 SE ECU on a 99 GLE Body? Is that going to work? Just trying to figure out if I will have any chassis control issues.

KRRZ350

iTrader: (29)

Yup, you got it, allthough even with the '99 exhaust you could get rid of the cel's for the rear o2 sensor, in fact it might not even be a concern, however an aftermarket y-pipe and an o2 simulator would be the move for better gas mileage and insane power increase, y-pipes kick ***. But back on topic.....on '99 cali's there are 4 o2's, the two rear sensors are located directly behind the pre-cat's, on all previous models there was only one post-cat o2 sensor and it is located either in the cat or right behind it and the wires run up underneath the drivers seat, so regardless you will now not have a spot to put that o2 sensor and would need to do some hard wiring directly to the ecu and add a bung to the exhaust or extend the wires from the post cat o2 sensor that went to the same terminals all the way to behind the cat and add a bung, it would be easier to just wire up an o2 simulator imho.

Yes, don't worry about using a SE ecu either, if you're searching on car-part.com they make it very very hard to do so because there interchange program comes up with like 15 different friggin options because they don't know the real deal.

phaze1

iTrader: (4)

Hmmm......now you got me thinking about that y-pipe. If I went with that, would I be able to pass emissions. Doesnt the y-pipe bypass the cats?

KRRZ350

iTrader: (29)

it bypasses the pre-cat, which only help with emmisions for the first 15 minutes, and then they are just a big restriction in the exhaust that decreases power and efficiency, many people here (myself included) have passed roller dyno emmisions with flying colors, they do not cause your car to fail emmisions.

oldngivout

iTrader: (8)

Don't forget that the 99's had an electronic EGR valve. And NATS.

You will either have to use the 97ECU/97 EGR valve or 99 ECU/99 EGR.

Of course you could also ignore the inevitable CEL.

phaze1

iTrader: (4)

Ok guys, here is where im at........when I initially posted this thread, I called around and found an ECU and harness off a 99 fed spec SE manual. Well, when I drove 3 hours to go pull the parts, it ended up being a cali spec car (the guy didnt know what he was talking about). So, I have decided, since the motor only has 61k on it and its untouched, i'll just buy the whole freakin motor and be over with this s***!! My car is originally a 99 cali spec GLE, so atleast now everything will match. I decided to buy the ECU and harness along with it, because its in mint condition. Will I have any problems using the 97 manual trans with the new 99 SE cali spec engine/ECU/harness?

KRRZ350

iTrader: (29)

Tranny will be fine, wow, you're going all out though, it does seem a little excessive to me just because of the down time of the car versus working out the codes and bugs and wiring here and there......... But more power to ya', that's cool that you'll have an engine w/60k when all is said and done, I have a carfax account right now also if you want me to verify it PM me the vin.

phaze1

iTrader: (4)

Yeah, just like the fact that it had low miles. The extra parts here and there were just a big headache. JN1CA21D5XT818424, thanks!!