This thread was saved without dates. "Around Jun 2004" is estimated from neighbouring threads.
hey i went to the junk yard and got out a 87 300zx z31 o2 sensor and tryed it on to a 200sx v6. the z31 o2 is way bigger than the 200sx 02. i thought it is a direct fit? so how does people who have done it, do it? i also got out a '85 300zx ECU, but it look just like the '88 that i got out of( does all the 300zx z31 ECU have a number on it? both of mine 85 and 88 is number 28), and the '88 ECU is making my car dying because of my 200sx o2 sensor.
any info is great
Only a certain range of 1986 Z31 300ZX's used the same o2 sensor as our S12's. To use the more common fatter one used in the 300ZX, you can have an exhaust shop weld a new o2 bung on that will fit it. Yes, the 300ZX ECU's look the same as the S12, but they supposedly have just a little more aggressive tuning. You need to make sure that the o2 sensor you have matches the ECU you're running. If you're running an 85 300ZX ECU, you need to install that o2 sensor from the 85 300ZX.
does just putting in the 300zx z31 MAF work for the s12 without the 300zx z31 ECU??
just wondering.
I have not tried it. I know you can run a 200 MAF with a Z31 ECU, so I don't see why the reverse wouldn't work. Maybe someone here knows better than I do though.
I have to wonder what happened to Crowbar?? Haven't seen him about for a while.
He's the one to ask about this.
yea he was telling me about this awhile back. he seems to know alot about the o2. o well, im not in a hurry to do anything.
I tried the MAF & ECU thing in different pairs....first was the z31 MAF with the s12 ECU. HIGH IDLE! somewhere in the range of 1600 rpm..and didnt run that well, but thats my cars own issue, may work for someone else. AS for the s12 MAf w/ z31 ECU..way low, and stumbly idle (like 500 rpm, and would stall frequently). This seemed to run smoother (when it did, lol) but there was very little power (can we say loss of HP??). just some insight.
You can run 300zx MFU with stock ecu but it isnt really worth it. I have even run 300zx MFU with a 88 Maxima ECU byw. Ran great.
1986 300zx ecu will only work with 87-88 200sxse O2 sensor. You can run a 200sxse mfu (which is smaller but you really want a 300zx MFU)
I have also run a 87-88 300zx ECU in my car using the stock O2 sensor. I was able to do this by modifying the signal. 88 300zx has best performance but only 17-22 mpg.
I have a 86 300zx ecu tested good and will sell with 300zx MFU for 95.00
hey so when you say '86 300zx ECU, does the '85 300zx ECU the same as well??
i can't seem to find the '86 300zx. i can only find '85, '87 or '88.
When I say the 86, I mean the 86.
84 and 85 ecus I dont even bother with. They are so common and no one wants them. Even guys with 84-85 300zx can swap in a 87-88 ecu and get an upgrade (they may change O2 sensors but the bungs the same).
I have an 86 ecu for sale. Its tested good and I will test it with a matched MFU (Or you can send me yours to match to it).
If changing ecus/mfus heed the following:
1. make sure your stock setup runs OK, that is; it blows 4-4 LED codes. If not sure what that means, get a manual and learn it.
2. changing ecus is a swap in but mfus can be tricky. dont create air leaks or your car will not run right. basically the 300zx mfu is a larger diameter so you have to modify the tubing some how to make it work. not hard but it depends on your skill.
3. dont get your pantys in a bunch when first trying it out. i had one guy that put it all together and just let it idle and didnt even take it out for a ride. let the ecu learn the new setup a couple days before crying or trying to tweak the MFU (this is the LAST thing you do).
hey crowbar, you wanna shoot me an email at [email removed]? im interested in that ecu and afm that you have.
You can run 300zx MFU with stock ecu but it isnt really worth it. I have even run 300zx MFU with a 88 Maxima ECU byw. Ran great.
1986 300zx ecu will only work with 87-88 200sxse O2 sensor. You can run a 200sxse mfu (which is smaller but you really want a 300zx MFU)
I have also run a 87-88 300zx ECU in my car using the stock O2 sensor. I was able to do this by modifying the signal. 88 300zx has best performance but only 17-22 mpg.
I have a 86 300zx ecu tested good and will sell with 300zx MFU for 95.00
how did you modify the signal? just a resistor or will I actually have to spend money? I'm thinking of getting an '88 ecu...
I have a 88 ecu available. I modify them internally.
What kind of power increase are we talking about by using this setup.