Differences between Manual ecu and automatic ecu

alleykat2020 · Postby **alleykat2020** » October 18th, 2007, 2:40 pm

Recently changed from auto to manual on an rb20. Shortly thereafter developed problem of hesitating/ choking off/ behaving like gas starvation when moving of and at low revs. Changed fuel pump, plugs, cleaned injectors, cleaned throttle body, changed fuel filter. Problem still persists. Advised that the problem could be originating from the fact that the ecu was not changed, but the car ran fine for almost a week after the conversion before the problem started. Help!!! Been a month now and the problem seems to be getting worse. What's the difference between a manual and an auto ecu and can that be the cause of the problem? Any ideas ?

Aaron 2NR · Postby **Aaron 2NR** » October 18th, 2007, 2:41 pm

only tink i cud tink of is fuel mapping and rev limits

shotta 20 · Postby **shotta 20** » October 18th, 2007, 3:05 pm

rev limiter....

Anil_Sooknanan · Postby **Anil_Sooknanan** » October 18th, 2007, 5:51 pm

the difference is that the automatic wiring has a different maping on D from P/ N the shifter wiring is connected to the ecu to let it know if your on a gear to indicate engine load therefore what you did is just showing the ecu that your off a gear when your really on a gear when it's on a fuel saving maping and your trying to get a performace mapping out of it if you look at a RB wiring diagram you would see something called the inhabiter switch <<<<< explains it all

Postby **Hook** » October 23rd, 2007, 1:58 pm

^^^ thas one LOOOOOONG sentence boi...punctuation in yuh pwefm!

teichou · Postby **teichou** » October 23rd, 2007, 2:36 pm

Anil_Sooknanan i am guessing that you are to wire the inhibitor switch to show the ECU that it is in D so it will deliver sufficient fuel

i converted a cs3a lancer from auto to manual, wired the inhibitor to show D in the cluster and i get the same problem alleykat2020 complaining about, just mine at high revs and hill climb and my idle real erratic don't talk bout when d a/c on

xxSTAY TUNEDxx · Postby **xxSTAY TUNEDxx** » October 23rd, 2007, 6:29 pm

Hook wrote:^^^ thas one LOOOOOONG sentence boi...punctuation in yuh pwefm!

lol.

Anil_Sooknanan · Postby **Anil_Sooknanan** » October 23rd, 2007, 6:47 pm

well sorry guest i might stop posting anything untill i learn english

THE SYNDICATE · Postby **THE SYNDICATE** » October 24th, 2007, 7:09 am

Hook wrote:^^^ thas one LOOOOOONG sentence boi...punctuation in yuh pwefm!

(no offence eh)

Postby **Hook** » October 24th, 2007, 2:41 pm

Anil_Sooknanan wrote:well sorry guest i might stop posting anything untill i learn english

lol, no maaaaaaaaan...doh be sooooooo... :lol:

does this tranny come with a "PWR/ECON/MANUAL" selection option?

cuz if so, then it can be hardwired into power mode or maybe manual mode to accomodate conversions, no?

SCHOLARS · Postby **SCHOLARS** » October 24th, 2007, 8:05 pm

anyone one knows if the 4g92 mivec has a manual brain? i recently converted from auto to manual and after i did that i start getting a break up, sputter or what ever u want to call it in first gear only at 2500 rpm to 3900rpm.

Anil_Sooknanan · Postby **Anil_Sooknanan** » October 30th, 2007, 7:35 pm

Anil_Sooknanan wrote:
well sorry guest i might stop posting anything untill i learn english

you know what i take this back because i'm not going to let any fools here bring me down :!:

and to go with it my line of work has nothing to do with cars it's only a hobbie stop for a while think what am i and where am i going to be then yap :lol:

Postby **Hook** » October 31st, 2007, 11:32 am

yes...go brave!

OldSkoolRule · Postby **OldSkoolRule** » November 1st, 2007, 3:12 am

wey dread! fellas gettin sensitive and toting feelings an 'ting! Anyways, the RB auto ECU would have features built in to help the engine and the tranny co-exist as smoothly as possible. for example, it might have a slightly different map for acceleration enrichment, the AAC/IACV or idle control valve might be activated by the ecu when the vehicle is in gear and moving under a certain speed. in addition to the ECU having idle-up the engine when tranny is in gear, etc. In generl, the engine's ECU and the tranny's ECU communicate to achiev best performance under the given condions; for example timing of gear changes, down-shifting under loaded conditions, etc. Boy, is real ting wit dem auto and manual ECU

teichou · Postby **teichou** » November 1st, 2007, 12:09 pm

by chance does anyone know if the 2002 cs3a lancer has a tranny ECU or just one ECU that controls both engine and tranny?

Langdon · Postby **Langdon** » November 2nd, 2007, 11:38 am

switch it back and see

OldSkoolRule · Postby **OldSkoolRule** » November 5th, 2007, 3:01 am

Anil_Sooknanan wrote:the difference is that the automatic wiring has a different maping on D from P/ N the shifter wiring is connected to the ecu to let it know if your on a gear to indicate engine load therefore what you did is just showing the ecu that your off a gear when your really on a gear when it's on a fuel saving maping and your trying to get a performace mapping out of it if you look at a RB wiring diagram you would see something called the inhabiter switch <<<<< explains it all

Soldier, i have all circuit diagrams and system diagrams for ALL RB's, including the R32 All Engine and R32 Full Service manual. i ain't see no 'Inhabitor Switch' yet!;maybe i overlooked it, but care to explain. yuh really lost meh dey with da one! 'Inhabitor Switch'???

thegtiman · Postby **thegtiman** » November 5th, 2007, 5:46 am

OldSkoolRule wrote:
Anil_Sooknanan wrote:the difference is that the automatic wiring has a different maping on D from P/ N the shifter wiring is connected to the ecu to let it know if your on a gear to indicate engine load therefore what you did is just showing the ecu that your off a gear when your really on a gear when it's on a fuel saving maping and your trying to get a performace mapping out of it if you look at a RB wiring diagram you would see something called the inhabiter switch <<<<< explains it all

Soldier, i have all circuit diagrams and system diagrams for ALL RB's, including the R32 All Engine and R32 Full Service manual. i ain't see no 'Inhabitor Switch' yet!;maybe i overlooked it, but care to explain. yuh really lost meh dey with da one! 'Inhabitor Switch'???

Anil has a point.
Autobox PCMs are calibrated differently to manual ones.
The transmission inhibitor switch (the one that has PRND321 contactors) can tell the engine PCM via the TCM which gear it is in and allow the engine controlller adjust for idle speed ,anit jerk, frictional losses and reduced spark angle.
If you do have the RB20DET/RE4R01A diagrams from the A31/C33 Nissan workshop manual you would see this reference to the transmission inhibitor in there.
Manual JECS PCMs tend to have a higher rev limit as well.

boogy · Postby **boogy** » November 5th, 2007, 8:13 am

Postby **Ignorant Ignis** » November 5th, 2007, 11:18 am

SCHOLARS wrote:anyone one knows if the 4g92 mivec has a manual brain? i recently converted from auto to manual and after i did that i start getting a break up, sputter or what ever u want to call it in first gear only at 2500 rpm to 3900rpm.

yes ... u have to get the manual ecu ..... i did a cb3 swap using the 4g91 ...the engine came auto and i had to buy the manual ecu to get the car to run properly ..... the manual ecu also had a higher redline and more aggresive fuel map. but it was real easy to find ..... the code on the ecu would be the same ... but the code should start or end (can't remember) with "m" and not "a"

teichou · Postby **teichou** » November 5th, 2007, 12:53 pm

looking for a manual ecu and harness for a cs3a

ae101 enhanced · Postby **ae101 enhanced** » May 28th, 2018, 8:45 pm

wassup guys I have a 4age 20valve blacktop that come 6 forward gearbox and manual ecu however my ecu is damaged and I need a new one but a 6speed manual ecu kinda hard to find a guy have an automatic 20v ecu to sell me but I want to know 1st if it will function the same way or will it put me in problems??

TurboSingh12 · Postby **TurboSingh12** » June 27th, 2018, 11:32 am

ae101 enhanced wrote:wassup guys I have a 4age 20valve blacktop that come 6 forward gearbox and manual ecu however my ecu is damaged and I need a new one but a 6speed manual ecu kinda hard to find a guy have an automatic 20v ecu to sell me but I want to know 1st if it will function the same way or will it put me in problems??

I dont see why it wont work.

Adam79 · Postby **Adam79** » October 4th, 2018, 6:48 am

Got a similar situation I have a Audi A3 s line 2,0 that a stupid random bloke helped me jump start when the battery died in the winter and somehow got the wires on the wrong way and gave me the thumbs up to try starting! It fried the ECU ect so I bought a A3 with same engine ect and when I collected it it's a automatic!?
So I have had to use it whilst trying to repair the first one.
And I am very tempted to swap everything over to my s line but will it work properly?? The more recent one is automatic with tectonic gears and I just want someone to tell me if it's worth doing