Classic FAST Q's: IAT and TPS setup, drivability issues??

[BIGONTS]

Got my motor freshened up over the winter and now I have a couple hundred miles on it and want to start dialing in the tune. Nothing changed as far as mods go, in my sig besides adding an Accufab 70mm TB. Car ran great last year on dyno, track and drivability.

However, I got some drivability issues after making parking-lot-type maneuvers that might be attributed to the following.

• However, one major change I believe. I relocated the IAT sensor to the back of the lower intake. I do not believe it was being utilized last year as it was just hanging by the filter. That's how I got the car. How do I know if it's working correctly or working at all? Any particular screen? What changes do I have to make to my tune as I believe the computer adjusts according to IAT sensor? I hear Cal on here comment on the importance of this sensor to your tune and FAST corrections??

• What should my TPS % be set relative the the setting in the FAST tune? I believe it should be either one point lower or a few? I set it last year, but forgot what it should be. I know you can just change the setting in FAST and not mess with setting it at the throttle body.

Few issues. NOTE, I did not have these last year besides backing up peddline after warm up?? Initially the car cold starts great and I can back it out without peddling, etc. Hight idle until temp hits 180. Runs and idles great at stop light, etc. and car drive it for hours. But, once I park it and restart when it's warm, put in reverse then drive 70% of the time it sounds like it's missing, sputtering and once I get it in drive it clears up bout half a block down or so??? I know that trans is fully mechanical and the FAST does not communicate with it as far as D, R, N, etc. goes?

Any input is greatly appreciated.

Thanks

 

[norbs]

What you need is to add after start fuel after the hot soak. You need to adjust the amount of fuel and the time it is being removed. That would be in this table to start increase the values at the coolant temperature it is running bad by about 3% for now. See if it improves. Your tps is not that critical about 8-12 at idle I have seen with the classic fast. The IAT temp does effect the whole system, so you will have to re tune your map.


I made it a pdf so you can zoom in.

 

[norbs]

Not sure if you can read the text on that pictue , but its afterstart vs CTS. TABLE
The second table to adjust is the after start decay vs cts. What this table does is pull out the added fuel based on the number of crankshaft revolutions since the car started. Increase the graph and the fuel gets pulled out slower decrease the numbers the fuel gets pulled out faster.

If you do a data log you can log AFT. Correction ,in your log and see how much is being applied and how long it is in effect. You will want to adjust this to maintain at least about 13.7~14.1 in gear.


Please be advised that the you will not be able to enter closed loop if there is any AFT. correction present it must decay out to zero 1st.

 

[BIGONTS]

Thanks for all the help norbs. I will check the settings when I get home tonight. Last night my buddy who's very good with Classic FAST looked at my tune and we got it to run better.

However, my wideband O2 is not working. Just stays at 14.5. We tried a known good sensor and the same. It worked last year before I rebuilt the motor?? I need to figure out if it's a wiring issue or the FAST box. Any tips??

I'm running the Precision jumper harness and I've heard people have issues with them. Caspers is the way to go as far as the jumper harness goes. He's local so I'm considering that.

But.....Now I'm considering upgrading to a FAST XFI if Cal is running any trade-in specials.

Thanks again

 

[ULOSE2A6]

There is an O2 Option file you might have to get from FAST if you changed the O2. It is less than $20 from FAST and they e-mail it to you.

Regards,
Shev

 

[BIGONTS]

There is an O2 Option file you might have to get from FAST if you changed the O2. It is less than $20 from FAST and they e-mail it to you.

Regards,
Shev

Thanks Shev. However, I did not change O2's as this is the one that worked last year. We tried another known working one and had the same error.

 

[norbs]

What is your UEGO(R) voltage?

 

[BIGONTS]

I'm not sure what's going on. Seems to be working today?? Didn't touch the car since parking it last night.

Check these out with both my new laptop running Vista, didn't work last night??

I didn't try my old Dell last night, but we tried another computer and it still didn't read?? And swapped o2?

New Dell running Vista

Temp: 169
UEGOR V: 1.94
UEGOS V: .47
UEGO V: 3.06
TARGET A/F: 13.4
ACTUAL A/F: 13.56

 

[BIGONTS]

Old dell??

old Dell

Temp: 158
UEGOR V: 1.94
UEGOS V: .47
UEGO V: 2.80
TARGET A/F: 13.4
ACTUAL A/F: 12.94

 

[BIGONTS]

Just in case it's hard to see. Switched laptops minutes apart while the car is warming up.


1st pic, old Dell

Temp: 158
UEGOR V: 1.94
UEGOS V: .47
UEGO V: 2.80
TARGET A/F: 13.4
ACTUAL A/F: 12.94

2nd pic, New Dell running Vista

Temp: 169
UEGOR V: 1.94
UEGOS V: .47
UEGO V: 3.06
TARGET A/F: 13.4
ACTUAL A/F: 13.56

 

[norbs]

Looks like its working to me. Was your battery weak in the car at the time?

 

[BIGONTS]

Ok, got about two hours of driving time today. I'd say the O2 works about 70% of the time. Never goes out while driving, only on start up.

Here's what it says when it's not working. You can tell, car not running as smoothly.

Temp: 167
UEGOR V: 1.94
UEGOS V: 1.02 RED???
UEGO V: 3.53
TARGET A/F: 13.5
ACTUAL A/F: 14.50 LOCKED, DOES NOT MOVE

 

[norbs]

I would say the sensor is just starting to show signs of going bad. Have you tried another sensor?

 

[XXQUICK6XX]

Pete you will have to get the unlock file to switch to another wideband.

Steve

 

[BIGONTS]

Pete you will have to get the unlock file to switch to another wideband.

Steve

Hey Steve. It's been a while. Been meaning to stop by and maybe your son can help me figure this out.

I just realized that. We tried a known good sensor and same error. A file needs to be updated/loaded for each new sensor. I just want to confirm it's the sensor and not anything else before I spend the cash on a new wideband sensor.

For some reason I don't believe it's a loose wire as it never turned off while driving and I drove it for 2 hours yesterday. Moved the wires around and it never shut off, when it was working.

Gonna cal Cal for some input and order a new sensor if that's it.

Thanks

 

[HighPSI]

Gonna cal Cal for some input and order a new sensor if that's it.

Thanks

I'm back in town this week. If you need any help give me a call

 

[ULOSE2A6]

Could it be a closed loop/ open loop issue? Since if it is in closed loop then the O2 corrections would be present but in Open Loop it would not be and lock onto the setting? You might want to look at the RPM settings for your closed loop.

Regards
Shev

 

[BIGONTS]

Could it be a closed loop/ open loop issue? Since if it is in closed loop then the O2 corrections would be present but in Open Loop it would not be and lock onto the setting? You might want to look at the RPM settings for your closed loop.

Regards
Shev

Checked all that. Everything is set up correctly. Thanks

 

[norbs]

It could be something in the box if the new sensor does the same thing? I would trade in for an XFI, so many more features than the classic box. Also closed loop cold start is now possible and self learning..

 

[BIGONTS]

The 02 seems to be working now, but it's dumping fuel at idle. The actual A/F sits around 9.7 and is in yellow? Idles really low and sounds like a big block with a cam??? On cold start, it does not go up in idle and sit there like it use to until it hits the certain temp?? Starts right up, but idles rough and rich at 800 rpm?? However, it drives fine and smooth and AF where it's suppose to be at?? FP regulator seems fine as it's set and 40 and goes up to 42 psi w/vacuum off. Gonna pull the plugs and see if anything is misfiring. I have a brand new coil pack BTW. Also getting a code 136 (see screenprint above). Does it mean anything. Any quick way to test each injector or harness? Also, timing might have moved?? Getting really frustrated Stepping up to XFI might be my only option.