MAP-ECU Tuning

[kapkaniMD]

I'm assuming that's the bosch inline pump?
yes it is and it sits in the litte right side compartment in the trunk area

Do you know if the in-tank pump is stock?
I have no idea, but I would assume so

Has the J-tube been bypassed or bored out?
I just bought a new tube and will be installing it shortly

OK, I doubt it's stock, but anything is possible.
as a matter of fact it is stock, is that a bad thing??

Ok now all together what does this all mean, like I said I just want to car to run normal at maybe 7lbs or so of boost, I also have a dual stage boost controller and wouldnt mind setting stage 2 a little bit higher

Also for the Vf voltage, are you simply just connecting lets say the ground to E1 and the pos. to Vf1 and reading the votage, and when you are doing it do you simply just adjust the values in the mapecu at the same time?

 

[kapkaniMD]

Hey, I went to start the car without the laptop connected and it wouldn't start like it did before I installed the new ECU, I believe I didnt save it like I was supposed to. Can you tell me how to save it to where I dont need to upload the file from the laptop every time

Supracentral: can you please comment on the info I gave above as well - thank you for all your help by the way

 

[Supracentral]

Hey, I went to start the car without the laptop connected and it wouldn't start like it did before I installed the new ECU, I believe I didnt save it like I was supposed to. Can you tell me how to save it to where I dont need to upload the file from the laptop every time

You shouldn't need to. Something is either wrong with your MAP-ECU or the wiring. Double check everything.

Supracentral: can you please comment on the info I gave above as well - thank you for all your help by the way

I'll try tomorrow. I've been a little pressed for time and I didn't want to leave you a half assed answer.

The quick comment would be that this car is pretty heavily modified, getting it to run fairly stock shouldn't be much of a problem, but that turbo is large enough that even at relatively low boost you are going to be moving enough air that it's going to require wideband tuning. Probably on a chassis dyno.

 

[kapkaniMD]

Ok car is running good again, however there is still the issue of tunning, the weird thing is, the mapecu continues to read rich, while my halmeter is reading at the bottom of lean and moved up maybe one or two spots after the car heated up..... So which one do I trust and how do I fix this, there is a bit of white smoke with a little black smoke that comes out on acceleration... Again the turbo is bypassed right now, should I hook it up before continuing anything?

 

[boostadikt]

I have a few questions that have not been totally answered, however i do appreciate being called ignorant and stupid because i did not know much about Vf, but this information has been very useful.

But what do you do when you are actually tuning for Vf, and not once in this thread has a wideband been mentioned. are you driving around looking at a voltmeter trying to keep it at 2.5V for your a/fs instead of a wideband? When i had my map ecu it was very touchy, but i had my car running smoothly on all boost levels, i tuned it just using my wideband and never worried about Vf, the problems i had with the map ecu, is my car would not idle when it was cold, and would hiccup BAD when driven cold, however it would run fine when warm. I attributed this to my lack of Cold start injector and ISC valve. It was just very touchy and even at the correct a/f's my car did not seem to run smoothly, I hated that you could not datalog with it and I had a hard time using the trace feature to actually adjust certain areas, overall it was just a pain in the ass to use, also i read many similar hate stories about how crappy it ran on karmen vortex cars.

Something i dont totally understand... you said that 4 strokes pull 20 pounds of mercury, and that that is only 10 psi, so on standard boost gauges and such when it says at idle im pulling 20 psi that is really lbs mercury but as soon as i cross into boost its into PSI? is the boost PSI that the map ecu reads the same as PSI the gauge reads?

I ended up getting sick of the map ecu, and put an AFM and Safc back in my car, hooked up the wideband, Still neglected Vf and tuned it out for 12.0-12.5 a/f's. It idles now, runs very smoothly, I tuned it in 30 mins, and it has not lost its tune yet.

I had never heard of what Vf does until your post here and in another thread.... I now know what it is and what it essentially does, but when do you acutually use it to tune? why does it matter if you are using a wideband? if your actual a/f's on a wideband are on target then shouldn't that satisfy Vf and keep it around 2.5 volts anyways?

 

[boostadikt]

also it seems in my mind that Vf would not make you loose your tune because it is pulling readings from your sensors and the narrow band o2, so if it really had a HUGE effect then it would actually help you tune.

I.E. your idling at 14.0 a/f the computer would see that you are rich and adjust itself to a leaner a/f and once back on target Vf would be satisfied. Once you were fully tuned with the map ecu then the stock computer will still be taking reading constantly and adjusting to keep itself on target.

Please Correct me if im wrong, but i still do not see when to use Vf while tuning when you have a wideband in front of you.

also can you explain exactly what is going on in Open and closed loop?

I dont mean to thread jack, im just trying to fill it with more information.

 

[pimptrizkit]

also it seems in my mind that Vf would not make you loose your tune because it is pulling readings from your sensors and the narrow band o2, so if it really had a HUGE effect then it would actually help you tune.

I.E. your idling at 14.0 a/f the computer would see that you are rich and adjust itself to a leaner a/f and once back on target Vf would be satisfied. Once you were fully tuned with the map ecu then the stock computer will still be taking reading constantly and adjusting to keep itself on target.

Please Correct me if im wrong, but i still do not see when to use Vf while tuning when you have a wideband in front of you.

also can you explain exactly what is going on in Open and closed loop?

I dont mean to thread jack, im just trying to fill it with more information.

well i have learnd some aswell.

lets see if i can awsner some of your questions.

vf is the ecu's out put, that we can watch to see how hard the ecu is working to keep the car running correctly, from what i understand, is that it read's from a base map, that toyota has designed and spent many thousands on to get the car driveble.

i too used to think the ecu monitored the n/b o2 sensor and made adjustments to the fuel trim by this and then relayed the amount pulled to keep the afr in check.
i found my self wrong, when i removed my n/b o2 and still found my vf working correctly!
the problem was i was tunning incorectly since the base map i was working with was so far off, (i think my fp is a bit off from stock, im running close to 32 w/ vac and 36/38 with out. is that to high?)
any ways, when i was tunning i noticed that my vf would be chilling around 2v's whitch was in the middle on my car, then drop to zero and my afr didn't change.

confused i decided to add fuel, did nothing but feel likei was hitting f/c when i got on it. so i started pulling fuel,
and i pulled some more, and the next thing i noticed is my car no longer bogged when i got on it, and i was now almost breaking new tires loose in slightly wet parking lot from rolling into the throttle hard.

i pulled some more out, and i noticed vf came back into play, and my car was now idling lean, and then it pulled down, back to 14.5's and 15's. to me it looked liked i satified vf,
it got rid of the hesitation i was having, the fuel cut i was expeicening, and also made my exhaust sound better. (imagine that!?>!~)


open and closed loop , closed loop the ecu is monitoring the o2 sensor for feed back and is making short term fuel trim adjustments based on feed back,

open loop, the ecu ignores the o2 sensor and read's more closely to the base map, and is no longer in economy mode,

 

[boostadikt]

right but whenever your a/fs are consistant and on target Vf should be satisfied..... also i always reset the ecu before i tune and i can always reset the ecu again and return to the base map that i tuned off of if it was loosing its tune

 

[pimptrizkit]

well if you noticed the post supracentral made theree are 5 voltages for vf,
vf can make corrections upto 20% or so, so if you tune in closed loop, say 5% lean, vf will richen the mixture back up, even tho you have "tuned" for 14.7 it's really the ecu healing it's self from the lean spot you have created, or the rich area.

what he also had said, that in order to put your own tune on you will have to fight vf,

so say i wanted my afr to go to 11.5 when ever i created positive pressure,

i would go to the 101.1kps mark on the map, and every thing above that i would add fuel , i have seen boost in 3rd and 4th gear while lugging it around at about 2/2.5k rpm.
this is still closed loop, and the ecu want's 14.7 i would have to add more then 20% fuel to get the mixture from rising back to 14.7 , this will set a rich code if driven in these conditions for to long.
if you max the ecu's capbilties to adjust fuel enough then you can finaly set your 2k rpm 2psi boost to run 11.5


if you pull some fuel, 5-10% you will notice the vf signal go from 2/2.5 volts to the next step up, say 3/3.75 volts, this is showing that the ecu is adding 5-11% fuel do it a lean condition it's fixing. vf shows a higher voltage, afr does not change!

but it does change for a second, if you watch it right after you make your change, you will notice the afr goes lean 15./16, possible 17afr, and then you will watch it lower back down to 14.7's and the vf will raise in voltage,

when your vf is set at 0 volt's the ecu is pulling the most amount of fuel it's capible of doing. if your afr still appears to be rich, and it's at zero, it's time to pull fuel.
pull small amounts and wait for the vf to re-act, if it doesn't, continue to pull fuel, 00, will change to 1.25/1.5v's and then the afr will lean out,


i ignored the vf information for awhile like you,
i got horribel gas milage, poor drivabitly, and poping and lose of power.

i tuned for vf on my brother's car and and his car drives great, after i learned from his car i have now started tunning for vf on my car, and the more i tune the more power and driviblity i have gotten out of my car.,

 

[pimptrizkit]

one thing i forgot to mention when vf isn't satified, and you are too rich, or to lean, tccs pulls timming to keep the combustion process safe, so this over all means NO power!,

just an fyi.

 

[kapkaniMD]

hey guys, due to a retard previous owner, my EFI fuse blew while the car was running cause the electric fans were connected to the black/red wire on the diagnostic port thing, anyways after fixing the fuse and disconnecting the fan, the car isnt starting, it will putter and backfire for the entire time the starter is turning but just wont run on its own for some reason, i uploaded the 7mgte550cc file onto the ecu while the car was in the on position before attempting to start it but it still wont start, it previously ran completely fine.... ANY body know what is going on or can help me??

 

[boostadikt]

i would use your old map that it was running on.... my car would not start at all with the 7mgte 550cc map from their site. i had to build a map from scratch to get it to run, try that and double check your fuse.

 

[kapkaniMD]

i would use your old map that it was running on.... my car would not start at all with the 7mgte 550cc map from their site. i had to build a map from scratch to get it to run, try that and double check your fuse.

well the car previously started without any map, but would only rev to like 3k rpm, when I added the 7mgte550cc map it, the car ran a lot better and would actually redline and would start right up every time, not it wants to start and you can tell there is a problem with the a/f ratio that wont allow it to run, it sucks cause it was running fine before this stupid fuse blew.... also, i dont have an owners manual and this weird light on the left of the guages is on that looks like a building with columns, does anybody know what the heck that thing is?? I dont care what I have to do I just want the car running again, if anybody can help please chime in

 

[boostadikt]

HAHAHAHA..... the warning light is low coolant, have you checked your engine, compression, fluid levels etc. you might have other problems, but i would check ALL your wiring and the fuse box again..... make sure the map ecu is wired correctly.

 

[kapkaniMD]

HAHAHAHA..... the warning light is low coolant, have you checked your engine, compression, fluid levels etc. you might have other problems, but i would check ALL your wiring and the fuse box again..... make sure the map ecu is wired correctly.

Ok low coolant is understandable since there was a leak where one of the heater hoses entered the firewall, but that is taken care of... there is no blown headgasket if that is what you are wondering, but as far as ALL the wiring what should I specifically look for, the mapecu is connected with the plug and play harness so there is no wiring problem there, and its not the same fuse also because when the fuse was blown the car wouldnt try to start it would just turn the crank, now it is turning and trying to start......thanks though

 

[boostadikt]

I really dont know then, if your fuses and wiring is good then i would assume its something with the programing of the mapecu, check all your calibration and settings.... i had mine set on AFM instead of VFK one time starting a new map , confused the hell out of me..... so make sure everything is set up correctly. other then that i can't think of anything

 

[pimptrizkit]

well does the w/b read rich or lean when the car is tring to start?

if the w/b cuts out wire it to a sperate batterie, that way it doesn' re-set when the car starts.

being to rich or to lean will cause hesitation and boggin/stutering problems.

 

[kapkaniMD]

the mapecu has always read rich when the car was running, but the a/f meter has always read extremely lean and moves only a little when the car warms up, so I dont know which one to believe. The car ran fine with the 550cc map so why would it be not starting now on the same map, Im not too sure what you are trying to say pimptrizkit, could you explain a little more. thanks

 

[pimptrizkit]

well you know how there's a heat up time for a wide band,

and when you turn your car on the w/b doesn't read.

what im saying is wire it directly to a 12v no a swtiched source,
so when you start your car it doesn't shut off then reset,

this way, you can watch the a/f content the very second it starts, it should be rich, some where around 12/13 and with in 5 minutes should come up to 14.7's (rough estiment,) it's the car's start up enrichment,

if this is too lean car wont start, and if it has to much fuel, well pretty much the same thing,

popping could be heard from both conditions, but different pop's

a lean pop is usualy loud from my experience, and tends to go out the exhaust,

rich poping usualy has black smoke come out at the same time, (exhaust) so


the sound of each pop is a bit different kinda hard for me to explain.
thats why it's easier to watch the wide band.

if you have any kind of ignition you should be able to tell on the wide band..

 

[tubbie]

From what I remember, the halmeter is just another light show meter, so please do some research on that a/f meter before trusting it.