How to correctly use a 94-97 B14 ECU in a 99 P11

[UNISA JECS]

I wonder what us 2000+ members need to do, also wonder if it will throw a CEL

I asked specifically javcrodgz yesturday on chat since he is using a 99 P11 engine harness on a 00+ P11 if the 3 sub connectors by the ecu (pictured below) match up and he said they did but i few pins had to be swapped around or what not, you might wanna ask him.





Im all down for sharing information as much as I can to help you all but I dont have a 00+ P11 but just form that info i'd start by using a 99 P11 engine harness and then applies the changes I have listed on this thread dependant on which ECU you choose to run.

[UNISA JECS]

93.5 uses the older blue plug OBDI ECU.

Well anybody reading this should know and if they don't this information only applies to OBDII ECU's, im not sure what the cut off date is but I think OBDII started 7/93 for the P10.

EDITED:

Ok according to Nissan FAST the Magnetic Sensor Assembly (23731-0J200 M/T) on the bellhousing on the transmission didn't start getting used to 01/94 so that should be the start of the OBDII ECU.

[aag20t]

Got a cel from moving pin 28 to pin 63 for iat

[UNISA JECS]

Got a cel from moving pin 28 to pin 63 for iat

Did you clear it and see if it comes bacl on cause I never got a cell for that with my 99 P11 using a B14 ECU.

[cono]

Unisa old friend... Whats up man... Pm me. My phone dont let me pm u. Shoot me ur number. U did det swap on my b13. I think u worked on all my cars except the jag.... This guy is the best mechanic around and i have mad respect for him... He wont stear u wrong.. Sorry for busting in this thread. Thanks

[cono]

What is the reason for using a b14 ecu instead of using a p11...

[Krist]

I am using a P10 ECU with a 99 engine harness in my 2002.
This is my notes for those connectors.



Some of these wires were consult that need to pass over to the OBDII plug under the steering column.
I didn't hook those up and still need to do so.

[srlucino]

if Im using a 02 engine harness and b15>to>b14 ecu step down harness, I need to do something like this, I bought it but, still dont have the time to look at it.

[StangG20]

Did you clear it and see if it comes bacl on cause I never got a cell for that with my 99 P11 using a B14 ECU.

this is a 99 p11 using a 95 p10 ecu. the code comes back instantly. swapped back to pin 28 and all is good

*edit* that was me posting from aag20t's phone yesterday

[UNISA JECS]

Unisa old friend... Whats up man... Pm me. My phone dont let me pm u. Shoot me ur number. U did det swap on my b13. I think u worked on all my cars except the jag.... This guy is the best mechanic around and i have mad respect for him... He wont stear u wrong.. Sorry for busting in this thread. Thanks

What is the reason for using a b14 ecu instead of using a p11...

What up Robert man I wondered what happened to your ass, imma shoot you my numbe rin pm.

[UNISA JECS]

Got a cel from moving pin 28 to pin 63 for iat

When you moved it to 63, 63 was occupied correct by the fuel tempature sensor right? You also just tape that wire off.

Also you need to disconnect the MAP sensor or your TPS wont work correctly if you using a 5 speed ECU B14 or P10 ECU.

[cono]

Ok i got it... Thanks unisa.... Ill be seing u soon man.. Take care

[89rodknocker]

Will these cars pass smog with the earlier ecu in them? Also is there any gain by just swapping the ecu on a 99 with a stock p10 ecu.

[UNISA JECS]

Will these cars pass smog with the earlier ecu in them? Also is there any gain by just swapping the ecu on a 99 with a stock p10 ecu.

That I dunno, im sure it'll pass smog if the use of the earlier style ECU is not some how detected by the SMOG check.

No there is no gain in just swaping in a stock P10 OBDII ECU into a P11.

[mister_rabbit]

Will these cars pass smog with the earlier ecu in them? Also is there any gain by just swapping the ecu on a 99 with a stock p10 ecu.

That I dunno, im sure it'll pass smog if the use of the earlier style ECU is not some how detected by the SMOG check.

No there is no gain in just swaping in a stock P10 OBDII ECU into a P11.

I am interested in the smog issue as well. Anyone have any experience in CA?

[UNISA JECS]

Time to revisit this thread

Re-worded or tried to make the things you have to do a little more clear

Move pin 63 from B14 ECU to position 28 of P11 harness

Combine pin 45 and 41 from B14 ECU to position 41 of P11 harness





Move pin 108 from B14 ECU to position 110 of P11 harness

Move/Splice pin 111 from B14 ECU to position 112 of P11 harness for ground for rear heated oxygen sensor




***Other important things

***MAP sensor must be disconnected or it effects the TPS for some reason****

I sure would like to investigate why this is with the MAP sensor




Other things to tackle is the emmissions crap

[ferrari21]

***Other important things

***MAP sensor must be disconnected or it effects the TPS for some reason****

I sure would like to investigate why this is with the MAP sensor

Other things to tackle is the emmissions crap

Great find, I always wondered why TPS voltage was inconsistent on certain startups. I'm stepping back down to a JWT B14 ECU in a few weeks, and getting my 96 g20 manual ecu fitted with Nistune in the near future. So this is really great information to know.

I haven't spent enough time with it to figure this out either, but I'm guessing something is going on with the 99's ground wires after the 2nd plug on the TPS (grey one) is no longer used with the older style OBDII ECUs. That's what I feel is causing wacked out voltage readings and causes high idle intermittently on some startups. Like I said, just a theory, when I jump back down to an older style ECU, I'll be able to confirm as I'll have a platform to zero in on the wiring.

[UNISA JECS]

Great find, I always wondered why TPS voltage was inconsistent on certain startups. I'm stepping back down to a JWT B14 ECU in a few weeks, and getting my 96 g20 manual ecu fitted with Nistune in the near future. So this is really great information to know.

I haven't spent enough time with it to figure this out either, but I'm guessing something is going on with the 99's ground wires after the 2nd plug on the TPS (grey one) is no longer used with the older style OBDII ECUs. That's what I feel is causing wacked out voltage readings and causes high idle intermittently on some startups. Like I said, just a theory, when I jump back down to an older style ECU, I'll be able to confirm as I'll have a platform to zero in on the wiring.

Its kinda strange its similar to how the knock sensor is supplied with 5v but when you check the knock sensor via back probe, a properly working knock sensor circuit will give you 2.5v, maybe mathmatically this can be proven as to why it draws down to 2.5v......now my question is, is this draw down happening do to resistance presented by the knock sensor itself? Can this somehow be the reason why the MAP sensor effects the TPS? Its wierd to me......

However I still feel that something is not right and if I cant figure it out with this B14 ECU I may be forced to try a P10 OBDII ECU since teh camshaft position sensor wiring is the same, that something else I need to further investigate I just feel that using the B14 ECU on my P11 that something is holding it back.

[ferrari21]

I know what you mean, it feels like you're trying to figure out a rubik's cube at times. Anyway, some really great insight here, I've had to learn a lot of this stuff on my own previously because of lack of write-ups. You share some excellent knowledge, and I'm going to try these things as I head into the magical world of boost this winter.

[UNISA JECS]