Calibrating the throttle body???!

rlees85

Ex. Club Member
Some of you know my cars tb has been knackered for a good time now, well its just got a whole lot worse, and i also think it is whats causing my car to no longer start very well.

I think ive managed to get a 2nd hand throttle body off a VERY low mileage micra.

Problem is i heard you have to calibrate the throttle posistion sensor? Is that true and if so how?

Sorry if im talking absolute rubbish lol :)
 
First i've ever heard of calibrating it anyway. Only way i could see to do that is fit the new one - set a good idle on it and then dissconnect the battery for an 1hr to reset the ecu.
 
Throttle bodies ??

Ok here shows I don;t know Micra's to well, maybe someone could post a pic of the engine inc. throttle bodies.

Only throttle bodies I know anything about are Webbers and even there my knowledge limited at best. Tuning throttle bodies is a fine art, get it right and your laughing, get it wrong and it's an expensive mistake usually ending in too much petrol going into the engine.

Micra's use throttle bodies as standard, really... Wow, there must be a fair amount of tuning to do :D

I'm learning every day but learnign to appreciate these cars more and more...
 
the k11 has a single throttle body at the top of the engine at the back of the bay not throttle bodies as in 4 of them for performance.

its what allows the air into the engine.

:)
 
the inlet is also fairly small on the throttle body. This can be increased by using one off a bigger nissan like a 1.6 primera, but the primera ECU must be used accordingly. I have my doubts about this mod :s

not really realevent but i thought i would share it anyway :D
 
K11 ECUS __DO NOT__ learn, disconnecting power will do NOTHING more than clear fault codes, and base fuel adjustment...

Yes the throttle position sensors do need setting, however if it came from another K11 and has not been touched it should be fine. I dont know off hand what the throttle closed voltage is, so I wouldnt worry about this for now.

Ed
 
ok cheers that clears things up nicely, are you sure k11 ECUs dont learn anything? i remember a long time ago, before i had this k11, nissan reset the ECU when they couldnt find the problem, to try and cure it.

Was a post 2000 model though and they have different ECUs i think..
 
Ok - maybe the don't learn. But surley if its disconnect the memory in it is lost so therefore when the new tb is put it - it would adapt it to suit?
 
From my limited knowledge of the skyline TPS it should be set correctly so that the voltage reading at closed is what the ECU expects to see...if it's not then the ECU can't accurately provide fuelling etc.

I would (assuming your engine is otherwise running ok) try it and see how it runs. If it's not right then look for info on setting the TPS.

My 2p
 
Ed said:
K11 ECUS __DO NOT__ learn, disconnecting power will do NOTHING more than clear fault codes... Please drop this myth.
Ed

a reset of the ecu will clear fault codes, and Clears the self learn data, this is normally the adjustment under feedback to reach the target a/f and a couple of other ecu settings ed.

nissan ecu's do learn, and this includes k11's, that is the reason there is a ecu command that clears this "self learn" data, and a different one for clearing fault codes.

you can reset the base correction when the car is running to monitor changes.

sometimes this data can "hiccup" hence why nissan still reset ecu's to factory settings, if you find your car running very rich / lean this can be the case.

and its a good test for the lambda sensor.

resetting the ecu won't help you with more power, nor setting up your t/b, the only time its worth a shot is if your car isn't running correctly.

however leaving the battery unplugged doesn't always work and most of the time the ecu will immediately adjust, consult is the only way to reset it correctly
 
I guess complications start with what you consider self learning, I dont consider the K11 as a true self learn, that is only lambda feedback. it does not ajust engine dynamics to suit driving style for example. Its also only a narrow band feedback and so is fundementally flawed in this sense anyway. Other than ajusting base fuel map and closed loop afr please point out what else the ecu 'learns'? There is a difference between trimming maps by feedback and an ECU with a true ability to almost self map and learn different enviroments and conditions. The K11 is very limited in this respect.

The later K11 (renault) Bosch Motronic ecus however are very advanced in this sense, they can compensate and ajust for an amazing amount of stuff, Disconnect an injector in a K11 and it will idle rough, it wont get any better. Disconnect an injector on the Motornic it will idle rough for a moment then settle back to almost normal. alas, on 3 cylindars, so well that it does this some probably wouldnt even notice.
 
Ed, please re-read my posts, as i say

"this is normally the adjustment under feedback to reach the target a/f"

you say

"Other than ajusting base fuel map and closed loop afr "

i agree

in regard to "an ECU with a true ability to almost self map and learn different environments and conditions"

self mapping doesn't seem like the best idea, hence why few manufacturers build it into their code, also the k11 ecu responds very well to different conditions, due the the high amount of "maps" it has access to.

:)
 
I will settle with the fact that our views on what is a self learn ecu and what is not are different! I don't consider the features of the ECCS ecu to be advanced enough to class it as a true self learn ecu.

I feel that people on the whole get very carried away with "leave your ecu disconnected overnight" etc comments as when they plug it back in, it will in most cases be exactly where it was again as soon as the engien is upto operating temperature!
 
Ed said:
I will settle with the fact that our views on what is a self learn ecu and what is not are different! I don't consider the features of the ECCS ecu to be advanced enough to class it as a true self learn ecu.

I feel that people on the whole get very carried away with "leave your ecu disconnected overnight" etc comments as when they plug it back in, it will in most cases be exactly where it was again as soon as the engien is upto operating temperature!

i'll agree again

59 bhp is more than enough - its open and closed, depending on conditions :)
 
ok ill jus stick it on and see how it goes, one last question tho, where do i get a gasket from to fit it onto the inlet manifold? and how much for roughly? cheers!


edit: jus for a note, i rekon mine is a later k11, with a bosch motronic ECU :)
 
59 bhp is more than enough said:
what cars do have self learn ecu's on them? just curious thats all. so there are two types of closed loop engine mangament systems.

ive been lead to believe that the MR2 turbo has one.
 
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