Datalogs going from normal to rich within minutes of startup
08-30-2014, 02:11 PM
#1
Melting Slicks
Thread Starter
Datalogs going from normal to rich within minutes of startup
Hi guys. My car is running better however when I datalog it, the o2's start in the mid 450's and then end up near 900 after a few miles of driving.
My wideband still needs to be calibrated, but it supports the trend going from somewhat rich, to rich by the end of the drive.
Any ideas why this is happening? The car's actually driving very good at startup. It still drives good after a few miles but I don't have enough seat time to really discern yet.
Here are some logs; 1st one is immediately after startup. 2nd one is crusing to the drive through about 1/2 mile into the drive. 3rd one is on the way back from the drive through after about 2 miles of driving and going through the drive through.
My wideband still needs to be calibrated, but it supports the trend going from somewhat rich, to rich by the end of the drive.
Any ideas why this is happening? The car's actually driving very good at startup. It still drives good after a few miles but I don't have enough seat time to really discern yet.
Here are some logs; 1st one is immediately after startup. 2nd one is crusing to the drive through about 1/2 mile into the drive. 3rd one is on the way back from the drive through after about 2 miles of driving and going through the drive through.
Last edited by qwiketz; 08-30-2014 at 02:22 PM.
08-30-2014, 05:48 PM
#2
Melting Slicks
How are you adding fuel for boost? I don't remember on the DA2 if there is a table for coolant temp and addition fuel. Has any of that changed in your programming? Is the coolant temps seen by the ECU correct? Just trying to get the ball rolling here.
I can't view the logs here at work. It's blocked......
I can't view the logs here at work. It's blocked......
Last edited by ANTI VENOM; 08-31-2014 at 09:21 AM.
08-31-2014, 01:31 AM
#3
Race Director
The short and long term fuel trims were stuck at 128 for almost all of the logs. That shows that the ECM is in open loop mode. That contradicts what the logging program is saying...
I would be interested in what the coolant temperature is doing during all this. I didn't see that in the logs.
I would be interested in what the coolant temperature is doing during all this. I didn't see that in the logs.
Last edited by Cliff Harris; 08-31-2014 at 01:34 AM.
08-31-2014, 10:46 AM
#4
Burning Brakes
I have to agree with Cliff, there is no fuel correction. The only time I noticed any sign of fuel correction was on the 2nd video at about 36sec mark, which lasted for 8 secs. It is my opinion that you are in constant PE mode. Something in your BIN is putting you in constant PE mode To answer Cliff's concern about coolant temperature it shows to be around 200F. My biggest concern however is the fact that you are in constant Spark Retard. Also, it shows that you have a DTC error. Can you verify what DTC error is being indicated? I would love to analyze your BIN if you could post it up or PM me with it.
Last edited by FrankieD; 08-31-2014 at 10:49 AM.
09-01-2014, 06:30 PM
#5
Melting Slicks
Thread Starter
hi guys. Thanks for the input. I spoke to the original tuner, mobandy, and he recommeneded that I take a look at the fuel enrichment vs temp tables.
I just got in from out of town so I'll be checking it out over the next few days. I bought some new chips from moates so I can make some variations of the tune and see what works. I'll keep you posted.
I just got in from out of town so I'll be checking it out over the next few days. I bought some new chips from moates so I can make some variations of the tune and see what works. I'll keep you posted.
09-01-2014, 06:31 PM
#6
Melting Slicks
Thread Starter
How are you adding fuel for boost? I don't remember on the DA2 if there is a table for coolant temp and addition fuel. Has any of that changed in your programming? Is the coolant temps seen by the ECU correct? Just trying to get the ball rolling here.
I can't view the logs here at work. It's blocked......
I can't view the logs here at work. It's blocked......
09-02-2014, 02:17 AM
#7
Melting Slicks
10-22-2014, 09:48 PM
#8
Melting Slicks
Thread Starter
Hi guys. Here is the open loop % change to afr versus coolant temp chart from my bin file.
-40 - 94.53
-20 - 74.22
-16 - 57.03
-4 - 89.84
8 - 78.91
20 - 69.53
32 - 63.67
44 - 63.67
56 - 63.67
68 - 63.28
80 - 69.53
92 - 63.67
104 - 63.67
116 - 63.67
The car is getting progressively RICH according to the o2's as I mentioned. Where would be a good place to start with these values? I don't quite understand them and how the # on the right works. Anyone have a rough explanation?
-40 - 94.53
-20 - 74.22
-16 - 57.03
-4 - 89.84
8 - 78.91
20 - 69.53
32 - 63.67
44 - 63.67
56 - 63.67
68 - 63.28
80 - 69.53
92 - 63.67
104 - 63.67
116 - 63.67
The car is getting progressively RICH according to the o2's as I mentioned. Where would be a good place to start with these values? I don't quite understand them and how the # on the right works. Anyone have a rough explanation?
Last edited by qwiketz; 10-22-2014 at 09:50 PM.
10-23-2014, 12:12 AM
#9
Race Director
I pulled this table out of my stock BUA EPROM:
The main difference I see is that in the stock tune the percentage is going down as the temperature goes up, whereas yours is the opposite.
Code:
;--------------------------------------------------
; OPEN LOOP A/F % CHANGE vs COOLANT TEMPERATURE
;
; TABLE = 2.56 * % CHG TO AFR + BIAS
;--------------------------------------------------
LC41E: FCB 221 ; Open Loop AFR Bias to Set up Lean Limit (86.3%)
; AFR = 20:1 EXAMPLE
; 14.7 * 256 = 189
;--------------------------------------------------
; % CHG TO AFR deg C COOL
;--------------------------------------------------
LC41F FCB 89 ; 34.8 -40
LC420 FCB 68 ; 26.6 -28
LC421 FCB 64 ; 25.0 -16
LC422 FCB 53 ; 20.7 -4
LC423 FCB 49 ; 19.1 8
LC424 FCB 35 ; 13.7 20
LC425 FCB 25 ; 9.8 32
LC426 FCB 25 ; 9.8 44
LC427 FCB 25 ; 9.8 56
LC428 FCB 25 ; 9.8 68
LC429 FCB 25 ; 9.8 80
LC42A FCB 25 ; 9.8 92
LC42B FCB 25 ; 9.8 104
LC42C FCB 25 ; 9.8 116
10-23-2014, 08:24 AM
#10
Burning Brakes
values from my '93 BIN are as follows. You are definitely adding way too much fuel; for reasons not sure. Care to attach your BIN for analyzing.
-40 39.06
8 16.41
56 9.38
104 9.38
152 32.42
-40 39.06
8 16.41
56 9.38
104 9.38
152 32.42
10-24-2014, 02:34 AM
#11
Melting Slicks
Thread Starter
I looked at my original bin file and at some point, these figures got changed quite a bit. I was at 13 for most of them in the original bin if I remember correctly. That explains a lot.