Tuning a Classic FAST

dont worrry about the iac PD ,, be concerned about the iAC target
iac is too high ..your tps base should be moved up to 10-13 and check that under idle parameters that the min tps for idle is greater than the tps at idle
the throttle follower wont allow iac to go below the line based on tps ... scale down the throttle follower so that at tps base it will allow the iac to go to atleat 10 , and then youll see the true iac target and you may need to adjust the throttle blade screw and reset the tps accordingly , just as you would do on a chip

as to your actual af being 0.0 is confusing because you posted your idle af is 13.1 " A/F stays at 13.1 at idle (1,100 rpms) ".. looks like you have a mismatched wideband sensor for a box that doesnt have the any o2 option file or a dead sensor , without the any opt file the sensor needs to be numbered from fast and match the serial # on the box , with the any o2 file you can run any l1h1 sensor
with the sensor not reading you can forget about the airfuel table because your ecu wont track that wont run closed loop (no correction ) and will only run fueling based on whats programmed into the ve table +/- any correction based on tps , map, coolant, afterstart etc as if it was a programmable chip but without an actual wideband you cant tune the ve
 
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The TPS base parameters are listed with the IAC 'P' and 'D' gain as a % right? The TPS at idle was set at 6
 
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Scratch my last post. I just read your edit in your latest post. I emailed FAST already about the o2 sensor and they are sending me out the any 02 sensor programming.

Looks like a bad sensor then. I got in contact with FAST and got the O2 file. Damn are those Oxygen sensors EXPENSIVE! 179 was the cheapest I could find with the h1h1
I opened the Dash as its called while it was running and here are some more numbers
TPS 4%
Inj Dc 2.1
Lambda 0.00 (oxygen sensor I assume)
IAC Target 73-77
VE 24.3-25.1 (thats pretty bad efficiency)
Map -9.2
BPW 2.2
Spark 30.00
Uego 3.63
 
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ALRIGHT!!!! Wide band was bad or the people that owned it prior didnt know about the download from FAST to be able to use any wideband sensor. Either way it works...now that that is solved...

Here are some of my readings from Idling today. I did change a few things. Idled the car down from the 1100 rpm to 950. I thought it just Idled way too high. I did idle it down to 800 but thought I didnt want to go too far off the beaten path as far as a tuning perspective goes. Since this computer tuning is new to me.
Here are some of the readings.....
TPS- 7 ( i opened, what I will call the air bleed, since that is basically what it is. It controls the idle air.)
O2 correct .8-2.4
Lambda .88-93
Map 38-40
OP mode 47
IAC D term 1
Code 136
HR BPW 2.26
IAC target 49-58
UEGO 2.78-3.04
BPW (ms) 2.2
Map 8.8- 9.3
VE 25.1
IAC PTerm 0 -1
 
like tuning with a chip you need some key data but not all what you posted
need to know rpm , iac target , tps which have to be set before proceeding
forget about posting
Lambda .88-93
OP mode 47
IAC D term 1
Code 136
HR BPW 2.26
UEGO 2.78-3.04
BPW (ms) 2.2
Map 8.8- 9.3

no reason you shouldnt be able to idle at 800 with 13.1 AF
your tps is still low and your iac is high , screw needs to go in thats where you need to start first

what you normally want to see in your base ve dash right now to get the table set up in the idle area is
scaled Rpm , rpm, map, actual AF , 02 correction , coolant temp , inj duty, spark timing, battery(v), air temp (f), gross corr%, aft corr %
if the aft correction isnt at 0% you wont go closed loop
try to limit your logger dash to 14 or less channels
 
pacecarta said:
like tuning with a chip you need some key data but not all what you posted
need to know rpm , iac target , tps which have to be set before proceeding
no reason you shouldnt be able to idle at 800 with 13.1 AF
your tps is still low and your iac is high , screw needs to go in thats where you need to start first

what you normally want to see in your base ve dash right now to get the table set up in the idle area is
scaled Rpm , rpm, map, actual AF , 02 correction , coolant temp , inj duty, spark timing, battery(v), air temp (f), gross corr%, aft corr %
if the aft correction isnt at 0% you wont go closed loop
try to limit your logger dash to 14 or less channels
Click to expand...

Ok. The car is getting better. Since my last post I looked at the tune again. I was watching the laptop and was looking at the different screens and watched the blue line with the blue circle on it. Basically that floated as to where my target should be and where I was in the tune. I just led the green line to those points as smooth as possible in the programming. I obviously saved that tune under a different name in the program and left the original alone so if im doing something wrong I can always delete my error. Thus far doing that is leading me to exactly the target area's you have been leading me towards.

Thus far I got the tune here. Numbers were from the dash.
RPM 950-1000 (scaled was approx in the same range I looked at it I just didnt record it.)
Inj DC 1.8
Air Temp 71.8 (sensor isnt in the intake tubing yet)
Spark 30.00
Map 38
Actual A/F 13.1
O2 correction 0
ATS Corr 0
IAC target 24-30 (floated)
Battery volts stayed in the 13.7 range (I have an LT1 alternator too, if that matters)
Coolant temp was around 157 degrees or so. Fan was kicking on. Previous owner set that.
Gross Correct was at "0" as well. I watched it but didnt record.
TPS still needs to be set (well RE-set) though. It was showing a 6 when I was messing with the idle air screw. Its an Accufab TB too. If that matters
 
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Alright...Im going to reset the air bleed and the TPS settings before I move any further. I did set the TPS voltage once per recommendations off vortexbuicks website. I had it set to .37 volts (key on throttle closed) but I have since messed with the Air bleed. So I will close the throttle all the way and turn in the screw until it slightly opens the throttle blade and then reset the TPS the way I did it before. That way I know for sure not to mess with them again. A solid baseline if you will.
 
iac at 20-30 your idle screw is ok , just need to loosen the two 5/16 screws and move the tps up voltage should be same as chip .44 and that will result in a tps % just above 10%
 
I tried setting the TPS to the .44 v position and the car wouldnt even start. So I cleared that out re-set to the .38 and it started. Idle was crappy though. There must be a decent cam in the engine.
Im not certain its the TPS though. I did mess with a few things in between on the programming. Once I went back to the original program and changed the closed loop AFR to 13.1 it Idled great.

The Dash read as follows...
RPM 850-900
Batt 13.6
02 Corr. 24.2
Actual A/F 13.1
Temp 153
INJ DC 1.8
Gross Cor 0
Air Temp 77.4
Aft Cor- 0
Map- 37-41
TPS 11%
Scaled Rpm 929-1000
Spark 30.00
 
O2 correction is adding quite a bit fuel. In the VE table, raise the number in the cell the bubble is floating over.

Rick
 
Done. The numbers were 26 in those boxes. I switched them to 30, since the bubble was hovering over 2 boxes. 02 correction is now at .8
The dash now reads
850-900 RPM
Batt- 13.6
O2 Correct .8
Actual A/F 13.1
Coolant 151.6
INJ DC 1.8
Gross Corr. 0
Air temp 70.3
Aft Corr. 0
Map 40
TPS 12%
Scaled 878-904
Spark 30
IAC 37-42
 
Could my switch from NGK UR5 plugs to ac CR42 ts have changed anything? The engine didnt even want to idle at the 14.3 AFR with the AC plugs but it would idle all day with the UR5's. I know the 02 was bad at that point so it wasnt going into closed loop. Would going to one step colder range make that much of a change?
 
only if the plug were fouling or they were wet from fuel in which case no matter what plug you had the wet plugs wont fire
 
Drove the car around the block today. DAMN! No hesitation smooth shifts and the boost doesnt lag. Everything in the tune seems good thus fare.
 
if you want t0 post a .log and the .gct , just put them in a zip file and then it can be uploaded to the thread
 
I figured that. I got a tune off this site for an original 3.8 and it was compressed in zip form. Before I posted this i copied it to a disk.
 
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