FREE MPI help!

[igdrasil]

i turned the switch off and because im using dual aux injectors. I turned the fuel Cal down to -2 right now and some bucking went away. Before at about 11.5-12 afr it would buck so maybe I was maxing out the stock injectors? It cold right now here maybe about 40. The car just feels really really slow for running 12psi on a gt28rs...

Can you describe the bucking? Is it like a cut or just bog down?
Be Careful, bucking can be:

1. Running lean in some spots
2. O2 clamp NOT working
3. Pump starving
4. Not enough fuel pressure
5. Wide gap on spark plugs
6. Too much ignition advance
7. Too much fuel
8. Failures on electrical connections

 

[Bigg Tim]

i turned the switch off and because im using dual aux injectors. I turned the fuel Cal down to -2 right now and some bucking went away. Before at about 11.5-12 afr it would buck so maybe I was maxing out the stock injectors? It cold right now here maybe about 40. The car just feels really really slow for running 12psi on a gt28rs...

You need to have the switch on. This turns the O2 clamp on and without it, the ECU will see the extra fuel you are giving and try to pull it out. Disconnect the purple wires from the turbo module and turn the switch back on. That may have been your issue, the eCU was trying to pull the fuel out. Maxing the stock injectors shouldn't do that because I max mine out and add the extra fuel via the xtra injectors. You need to run with the switch on so you go into open loop when you are in boost. The ECU doesn't try to maintain STOICH while in open loop, so it will not try to pull your extra fuel out.

 

[sniper9]

alright, ill try that today, I will turn the switch back on. I put new plugs in and gaped them at .28. Now maybe pull even more timing out and see what happens. Thanks for the help.

 

[wicked]

tim-my problem hasn't been resolved,but I have been getting a MIL for B1S1 rich to long.

 

[Bigg Tim]

tim-my problem hasn't been resolved,but I have been getting a MIL for B1S1 rich to long.

sounds like you are trying to do to much tuning in closed loop. You know those dumb infomercials where they say "set it and forget it"? That's what you need to do for non boost. That should be the only way you are getting a code, is if the AFR during closed loop is cycling too much. Make sure on the MPI SW that while you are cruising, the AFR doesn't cycle more then 14-15 or you will throw a code.

I have all my non boost area the same number except for the first 3 or so rows and the first 3 columns. I have those numbers the same as my idle. So on my map, I have 3's in the first 3 column's and 3-4 rows high then the rest of the non boost is 0's. I set it that way by adjust the fuel cal so that when I cruise in 3 gear, or whatever, at the same throttle position the AFR stays cycling 14-15 and no more.

What else have you tried in regards to the other issue? You never sent me or posted up another datalog. Not the excel file, but a datalog. The datalog shows more then the file does. I don't rememeber but do you have xtra injectors or no?

 

[wicked]

yeah,I am running extra injectors,and thats odd you would say that about the closed loop.I run my closed loop holding in the 14.5-14.7 area,but I can't tell if the ST,or LT fuel trim are compansating for something,because for some reason our MOTIS won't let me look at fuel trims,or any other PID data on this car.

sounds like you are trying to do to much tuning in closed loop. You know those dumb infomercials where they say "set it and forget it"? That's what you need to do for non boost. That should be the only way you are getting a code, is if the AFR during closed loop is cycling too much. Make sure on the MPI SW that while you are cruising, the AFR doesn't cycle more then 14-15 or you will throw a code.

I have all my non boost area the same number except for the first 3 or so rows and the first 3 columns. I have those numbers the same as my idle. So on my map, I have 3's in the first 3 column's and 3-4 rows high then the rest of the non boost is 0's. I set it that way by adjust the fuel cal so that when I cruise in 3 gear, or whatever, at the same throttle position the AFR stays cycling 14-15 and no more.

What else have you tried in regards to the other issue? You never sent me or posted up another datalog. Not the excel file, but a datalog. The datalog shows more then the file does. I don't rememeber but do you have xtra injectors or no?

 

[Bigg Tim]

yeah,I am running extra injectors,and thats odd you would say that about the closed loop.I run my closed loop holding in the 14.5-14.7 area,but I can't tell if the ST,or LT fuel trim are compansating for something,because for some reason our MOTIS won't let me look at fuel trims,or any other PID data on this car.

Is that 14.5-14.7 on the WB or the MPI SW? Who cares what the WBO2 says, what matters is what the MPI SW says because that is what the ECU is seeing. Is the ECU seeing that range, because I don't think the range will be that tight with the ECU. The ECU should see from 14-15.

The WB will show you running 14.5 to 14.7 because the ECU is doing it's job, but that is the actual AFR, the ECU may be seeing more of a range and if the range is too much, it will throw the too rich code because it keeps on having to pull too much fuel to keep the AFR at 14.5-14.7 That's why I say look at the MPI SW, because that will tell you what the ECU is seeing.

What is ST and LT fuel trim?

 

[wicked]

Is that 14.5-14.7 on the WB or the MPI SW? Who cares what the WBO2 says, what matters is what the MPI SW says because that is what the ECU is seeing. Is the ECU seeing that range, because I don't think the range will be that tight with the ECU. The ECU should see from 14-15.

The WB will show you running 14.5 to 14.7 because the ECU is doing it's job, but that is the actual AFR, the ECU may be seeing more of a range and if the range is too much, it will throw the too rich code because it keeps on having to pull too much fuel to keep the AFR at 14.5-14.7 That's why I say look at the MPI SW, because that will tell you what the ECU is seeing.

What is ST and LT fuel trim?

ST-LT= short term,and long term fuel trims.
seeing those would show me how much the ECU is compensating.

I have all my closed loop VERY dialed,shooth,and nice,I just don't know how much the ECU is actually compensating to get it there.


what would a boost leak cause in this situation?,or maybe a manifold(intake) leak?

 

[Bigg Tim]

ST-LT= short term,and long term fuel trims.
seeing those would show me how much the ECU is compensating.

I have all my closed loop VERY dialed,shooth,and nice,I just don't know how much the ECU is actually compensating to get it there.


what would a boost leak cause in this situation?,or maybe a manifold(intake) leak?

That's the thing, are you doing too much closed loop tuning? From my experience, you do not want to do much closed loop tuning. Just make it like the stock ECU wants to see. I don't doubt the car feels smooth, but you need to know what the ECU is seeing so you can tell if you are adding too much fuel via closed loop.

So is the AFR on the MPI SW cycling between 14-15 while cruising at a constant throttle position and speed? Does it ever dip into the 13's? If it goes 13's or lower too much, the ECU will throw a rich code because it has to keep pulling more fuel then it wants, to maintain the 14.7 AFR. You can see what the ECU see's via the SW. The AFR IN and the analog out is what the ECU is seeing. Depending on that, you can tell if it is trying to compensate too much.

 

[wicked]

That's the thing, are you doing too much closed loop tuning? From my experience, you do not want to do much closed loop tuning. Just make it like the stock ECU wants to see. I don't doubt the car feels smooth, but you need to know what the ECU is seeing so you can tell if you are adding too much fuel via closed loop.

So is the AFR on the MPI SW cycling between 14-15 while cruising at a constant throttle position and speed? Does it ever dip into the 13's? If it goes 13's or lower too much, the ECU will throw a rich code because it has to keep pulling more fuel then it wants, to maintain the 14.7 AFR. You can see what the ECU see's via the SW. The AFR IN and the analog out is what the ECU is seeing. Depending on that, you can tell if it is trying to compensate too much.

it's staying constant.
Tim,I don't mean to step on any toes here,or offend you,but I know my way around a car VERY well.I know what the car normaly sees,and wants to see.
it's the MPI SW I am not to familier with,but even that,I am not lost with.
I know my problem is laying with some thing stupid,but I just haven't been able to dedicate the time to figure it out.
soon the car will be going down for A bunch more goodies,I will be testing things,and narrowing the field.

 

[Bigg Tim]

it's staying constant.
Tim,I don't mean to step on any toes here,or offend you,but I know my way around a car VERY well.I know what the car normaly sees,and wants to see.
it's the MPI SW I am not to familier with,but even that,I am not lost with.
I know my problem is laying with some thing stupid,but I just haven't been able to dedicate the time to figure it out.
soon the car will be going down for A bunch more goodies,I will be testing things,and narrowing the field.

It's cool, I understand you may know your way around, but I don't know how much you know and the questions aren't being answered enough for me to know. It's hard to try to help without specific info and datalogs. That's why I asked the questions I did, not to say your a dumb ass, but to help me know what's going on. You say it's consistant, but are you talking about hte AFR on the WBO2 or the MPI SW? That is what I need to know to try to help.

The only way you should throw a rich code is if you are tuning too much in closed loop PERIOD!!!!! (as long as the car is working properly) That is what I am trying to find out with your setup. But like I said, the not so specific info is not helping.

I am working with a local guy that get's rich codes and we took out the MPI and he still is getting the rich codes. So we have to try to figure out what is wrong with his car before we can proceed.

I apologize if I made you think that I think you're a dumb ass. I can understand how it may seem like this. But I just needed some basic info, that's why it may have sounded like that. No hard feelings.(thumb) How about a datalog of you cruising at a consistant speed and throttle position?

 

[wicked]

my SW shows me at a constant 14.2-14.9,and the wideband,and my narrow band both read the same.
you see the problem is that it will show me this,because if I added fuel to a 13 to 1, the ST,and LT fuel trim would compensate to to bring it back to stoichiometric,exept I would get a code for being rich to long.

the problem I see is that sice a scan tool cannot be used to see the fuel trims because of the MPI,I can't know how much extra fuel is being taken away.
BTW,I had a boost leak,fixed it,but still have the cut,but god damn this thing puls for a meassly 10 psi.

It's cool, I understand you may know your way around, but I don't know how much you know and the questions aren't being answered enough for me to know. It's hard to try to help without specific info and datalogs. That's why I asked the questions I did, not to say your a dumb ass, but to help me know what's going on. You say it's consistant, but are you talking about hte AFR on the WBO2 or the MPI SW? That is what I need to know to try to help.

The only way you should throw a rich code is if you are tuning too much in closed loop PERIOD!!!!! (as long as the car is working properly) That is what I am trying to find out with your setup. But like I said, the not so specific info is not helping.

I am working with a local guy that get's rich codes and we took out the MPI and he still is getting the rich codes. So we have to try to figure out what is wrong with his car before we can proceed.

I apologize if I made you think that I think you're a dumb ass. I can understand how it may seem like this. But I just needed some basic info, that's why it may have sounded like that. No hard feelings.(thumb) How about a datalog of you cruising at a consistant speed and throttle position?

 

[avarela86]

Just orederd MPI, going to do NA tune to get my feet wet with the system and then a couple weeks later goin turbo. Subsrcrizzle (boom07)

 

[Bigg Tim]

Just orederd MPI, going to do NA tune to get my feet wet with the system and then a couple weeks later goin turbo. Subsrcrizzle (boom07)

If your doing that, don't waste your time soldering it in because you will have to make changes to the wiring when you go turbo. Also, the N/A turbo module will not work for you with turbo, so unless you are going with xtra injectors, you will be wasting your time. I think the N/A turbo module doesn't provide extra fuel, only keeps the coils from frying when you leave the key on. You can always buy a turbo TM before you go turbo.

There are a couple people running N/A, so you should be able to find some help from them. I have tuned my turbo with an N/A type setup, so I know how to tune it, but I don't have any maps that would work.....sorry. Let us know how things go.(thumb)

 

[brealmp3]

ok, well we did my mpi install saturday! things went by quick and the install was straight forward. loaded up a map off of blthlt's mpi since we knew it was a good map. we took the car out driving and did a little road tuning. the car pulls really strong for just 5psi! the car is still a little rich as we didn't get to into the tuning since i have an exhaust leak and will be getting that fixed and then confirming that my wideband is reading correctly. But I have over 300 miles on the car since the install, and I've had no problems, issues, or lights! There is some buck every now and then, but i do have an older tm so it is a little more aggressive. but we are gonna work on that with some more tuning! so big thanks, to Bigg Timm, Barry(blthlt), and Jason(gboromsp)!!

 

[blthlt]

I'm glad to have helped ya Brent. I wish we could have had more tune time but you have a decent base map to go by now so you should be set. I just want to show my appreciation for Big Timm, Apoc Man, MPNICK and anyone else who contributes to the advancement of the MPI! I love the way it has changed my car. Great Job

 

[Bigg Tim]

Glad she is working out for you. Let me know when you get your laptop and I'll try to help you tune out the switch. Did I send you the screen shot that show'd a map I did with the switch being tuned out? Anyway, you got my number. Let's get er tuned!!!(thumb)

 

[avarela86]

N/A turbo module will not work for you with turbo, so unless you are going with xtra injectors, you will be wasting your time. I think the N/A turbo module doesn't provide extra fuel, only keeps the coils from frying when you leave the key on. You can always buy a turbo TM before you go turbo.

Woops then i hope i get the correct Module in the mail this week. I spoke with Nick and he said it was fine to tune N/A and then flip the turbo module on when i do the turbo install and that there will be some other things i will need to change? I musthave understood something wrong. I orderd the MPI T/M.

 

[Bigg Tim]

Woops then i hope i get the correct Module in the mail this week. I spoke with Nick and he said it was fine to tune N/A and then flip the turbo module on when i do the turbo install and that there will be some other things i will need to change? I musthave understood something wrong. I orderd the MPI T/M.

If Nick told you that then I would go by what he said. Maybe he changed it for you or something. I just assumed the TM's were different. If the man told you, then take his word over mine.(thumb)

 

[avarela86]

So I just got it in the mail today, it's so tiny! Well i can't waite to get this on already. Planning on doing it this weekend, hope all goes well and the cars runs fine. Im not building it up completely stock just gonna mess with the air/fuel mix to get the hang of how it works.