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futurevr4man
03-31-2013, 02:29 PM
hey guys,

just wondering if the 98/99 ecu's are more reliant or just more finicky when it comes to closed loop feedback?

would bad o2 sensors cause me to throw a code for (i cant remember the exact wording atm) "extensive time to enter closed loop function"? i haver never had this issue before until i switched to the flashable setup. now i get it on every startup and have to drive around with a cel unless i clear it.

i bought some new o2 sensors but i dont want to switch them out if what i have now are fine (i dont think they are, just saying).

thanks guys

Greg E
03-31-2013, 02:42 PM
Your car needs to be fine tuned. The code wants cycling O2s and after so long of driving around with the trims maxed, it throws that CEL.

futurevr4man
03-31-2013, 02:51 PM
hmm. ok

Chris@Rvengeperformance
03-31-2013, 04:01 PM
yeah it will do this if your trims are maxed or if one of your o2 signals is dead. Please post a log with both o2 sensors voltages.

futurevr4man
03-31-2013, 05:41 PM
Just to be clear, in order to get my trims back where they should be, I will need to make it run rich for a while (16 mins or so) and hopefully see them come back closer to zero?

futurevr4man
03-31-2013, 05:42 PM
Chris, I'm messing with the tune ATM. Let me see where I can get here then ill post a log or two

Chris@Rvengeperformance
03-31-2013, 05:47 PM
Just to be clear, in order to get my trims back where they should be, I will need to make it run rich for a while (16 mins or so) and hopefully see them come back closer to zero?

you don't really have to wait to know if you are getting close. look at the short term fuel trim. It plus the long term is the real trim in action. So, if you are +12 on long term and -3 on the short term then your long term is going to adjust out to +9 after a while. So, try to get the two close to zero, then drive the car for a while and see if it needs further adjustments.

futurevr4man
03-31-2013, 06:07 PM
how do you know so much man? i feel like all i have been doing is reading about this stuff, but no where have i read that. maybe i did and just didnt know it? makes me feel d-u-m dum.

Keyan
03-31-2013, 06:42 PM
Just to be clear, in order to get my trims back where they should be, I will need to make it run rich for a while (16 mins or so) and hopefully see them come back closer to zero?

or disconnect the battery, because that will set them back to 0...

Chris@Rvengeperformance
03-31-2013, 07:01 PM
how do you know so much man? i feel like all i have been doing is reading about this stuff, but no where have i read that. maybe i did and just didnt know it? makes me feel d-u-m dum.

Just watched all the evo ecuflash videos, read some of their threads on dialing in injectors, and of course read Greg's stuff. It helps that my job is in computers anyway.

futurevr4man
03-31-2013, 07:20 PM
or disconnect the battery, because that will set them back to 0...

yeah i did that, that way i can let them not be having to pull so much fuel. gives an easier starting point



my short term trims are polar opposites of eachother. really stange. i cant tell if my o2's are bad or not. they are definitely going to be a pain to replace

Greg E
03-31-2013, 07:29 PM
yeah i did that, that way i can let them not be having to pull so much fuel. gives an easier starting point



my short term trims are polar opposites of eachother. really stange. i cant tell if my o2's are bad or not. they are definitely going to be a pain to replace

Uh oh... Where did you get your ECU from? This happens when adaptor harnesses have the front and rear o2 pin swapped. :(

Try this for an experiment: disable bit 2 of periphery 0

This will trim the fuel based only on one o2 sensor instead of both.

Greg E
03-31-2013, 07:31 PM
how do you know so much man? i feel like all i have been doing is reading about this stuff, but no where have i read that. maybe i did and just didnt know it? makes me feel d-u-m dum.

Maybe I need to make a better tuning instructions thread...

futurevr4man
03-31-2013, 08:23 PM
Uh oh... Where did you get your ECU from? This happens when adaptor harnesses have the front and rear o2 pin swapped. :(

Try this for an experiment: disable bit 2 of periphery 0

This will trim the fuel based only on one o2 sensor instead of both.

i got it from adam. should i take it out and send it to you or someone else? if the ecu is tuning off of just one o2 sensor, whats to say its tuning off the correct one? or should i expect the readings to be different from the one than they currently are?


Maybe I need to make a better tuning instructions thread...

i was afraid you would take it like that. your thread is very informative. i am hoping after all that i have learned/am learning i can make a thread that can get stickied and ill try an go into specifics on idle, partial, and wot tuning. it can be edited if need be, but i am hoping to cover almost everything anyone needs to tune.

Chris@Rvengeperformance
03-31-2013, 08:44 PM
my trims have grown pretty far apart too. Rear is +9 , front is +1. I am hoping a fuel loop will close them up.

Weather has been changing a lot though too.

EASY way to see if your o2s are right. Unplug the rear one by the plenum. See which o2 voltage goes dead in evoscan.

futurevr4man
03-31-2013, 08:47 PM
hmm. fair enough. ill try that

Keyan
03-31-2013, 09:03 PM
Uh oh... Where did you get your ECU from? This happens when adaptor harnesses have the front and rear o2 pin swapped. :(

Try this for an experiment: disable bit 2 of periphery 0

This will trim the fuel based only on one o2 sensor instead of both.


when my o2s were swapped, my car wouldn't idle proper, or drive much at all. I doubt this is his issue.

Jesters Deadd
04-01-2013, 06:11 PM
i got it from adam. should i take it out and send it to you or someone else? if the ecu is tuning off of just one o2 sensor, whats to say its tuning off the correct one? or should i expect the readings to be different from the one than they currently are?



i was afraid you would take it like that. your thread is very informative. i am hoping after all that i have learned/am learning i can make a thread that can get stickied and ill try an go into specifics on idle, partial, and wot tuning. it can be edited if need be, but i am hoping to cover almost everything anyone needs to tune.

This is why I won't make harnesses.
You may have to flip the pin 75 and 76.
What is your car? a fed or cali and year?
PM me or email me. I'll help you diagnose the O2s.
What are your all your long term fuel trims reading?

futurevr4man
04-01-2013, 08:02 PM
i pm'd you, but so far all of my long term fuel trims have been going to +12.5, but yesterday i reset the ecu and added lots of fuel throughout. the idle is closer, still not perfect, and all of my trims are still at 0 currently (even after letting it idle for like 20 mins).

now, before everyone says or thinks things are fixed, my o2 sensors are still not reading super great. attached is a portion of a log, so you all can see what i mean about the readings being opposite. its strange is all i can say. i assume that my rear o2 sensor is bad due to it no cycling at all, its just a flat reading. and the front barely cycles, so it may be bad as well. idk :hum:

and i also want to claim that the trims MAY have been going straight to 12.5 before because i didnt have enough fuel. i have gotten more ballsy with my adjustments and in return, got things a little closer to where they probably should be.

my log:
http://sphotos-a.xx.fbcdn.net/hphotos-prn1/150097_10200171785596377_1067756902_n.jpg


p.s. something i have been wondering for a long time is the VE readout... is that just spitting out what value the ecu is reading from the table, or is it calculating it, and thats a target VE? i figure the first, but just to be clear...

p.p.s. how do i get the excel file to display only the selected items? i always check that little box... "display selected items only" within evoscan, but when it spits out the excel file, i end up having to delete like 10 columns in between all of the things i want to see.

Greg E
04-01-2013, 08:29 PM
It's supposed to be the VE look up table number.

I doubt your o2s are dead. Been telling you for a while now that you need to add a couple clicks to the MAFT as its telling the ECU there is less air than there really is. Thus you are running lean. You keep adding fuel to the intake, fuel and accel tables and it still isn't enough to get the narrowbands to cycle.

Greg E
04-01-2013, 08:31 PM
Also, there is no way to get excel to hide the empty rows. You gotta do it manually.

This is where Toni's Logworks program comes in handy. Takes the excell spread sheet and plots everything onto a graph.

Greg E
04-01-2013, 08:33 PM
when my o2s were swapped, my car wouldn't idle proper, or drive much at all. I doubt this is his issue.

Based on the log he posted, I agree with you.

futurevr4man
04-01-2013, 08:49 PM
It's supposed to be the VE look up table number.

I doubt your o2s are dead. Been telling you for a while now that you need to add a couple clicks to the MAFT as its telling the ECU there is less air than there really is. Thus you are running lean. You keep adding fuel to the intake, fuel and accel tables and it still isn't enough to get the narrowbands to cycle.

i am going to add some with the base knob, dont worry! i just signed papers for a job with my engineering degree today, and been busy with school. i just havent gotten around to messing with the car as much as i would like lately!

Greg E
04-01-2013, 09:44 PM
i am going to add some with the base knob, dont worry! i just signed papers for a job with my engineering degree today, and been busy with school. i just havent gotten around to messing with the car as much as i would like lately!

:lol:

kywhitelightning
04-02-2013, 06:32 AM
my trims have grown pretty far apart too. Rear is +9 , front is +1. I am hoping a fuel loop will close them up.

I thought I was alone and had some strange IM leak because my low trims stay 10% apart. I have dialed them to split the difference at 5 and -5 but I have some new injector gromets for the lower intake and when I do this I will be swapping the front 3 injectors to the back to see if the trims change with the injectors. The mid trims stay within 2 of each other and the high trims do as well. I have pressure tested and can't find a leak to distinguish the front bank from the rear. I did notice in the stock rom that the gain settings for closed loop feedback are a lot different from the front (25) to the rear (3) bank. I don't know if this has anything to do with that or not.

Jeff

Greg E
04-02-2013, 07:21 AM
Are you guys sure you don't have a crack in your front exhaust manifold?

Chris@Rvengeperformance
04-02-2013, 09:22 AM
Absolutely sure

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futurevr4man
04-02-2013, 09:50 AM
I am pretty sure I don't either.