SmaknaSS

iTrader: (1)

I have had my LC-1 permanently connected to the car for three to four years now with no problems. while trying to tune my car on 150 shot of nitrous and C16 from a stand alone my LC-1 started acting strange. My average AFR used to be in the 14.5 to 14.7 AFR range but now is up in the 16-17 AFR range. When I go WOT my AFR says that the AFR in as high as 17:1 AFR. I know this is not true because my car drives fine at part throttle and WOT. If I really were seeing 17:1 I should be pinging like mad but I'm not picking up any KR . My narrow band O2's seem to be working from the EFI scan logs too.
BTW, The LC-1 is not setting any codes and I did replace the WB sensor with a new one but it's still not reading correctly.
Besides checking wiring and grounds and what not, what other things should I check with these LC-1's?

gametech

iTrader: (1)

Could you have accidentally done the free air calibration when exhaust was stil in the pipes? I mounted the button on mine where it is a little too easy to accidentally hit, and have had this happen.

jetblast

does the lc-1 run on 9v battery when installed permanently ? if so change the battery.

SmaknaSS

iTrader: (1)

Thanks for the replies. I was able to configure the LC1 to out put 5Volts, then 4Volts, 2.45 Volts (Stoich) all the way down to 0 Volts so I know the outputs of the LC1 are working. When I set the output of the LC1 to 2.45 Volts (Stoich), I viewed the reading with EFI Live and Efi live was reading 14.7 AFR so I do think EFI live is reading correctly.
So far I have replaced the O2 sensor, Checked the wiring, Checked the outputs of the LC1 and checked to see if EFI live is reading correctly. Just for the hell of it I think I will start logging again to see if it working again.
BTW, the voltage powering the LC1 is fed by the post cat O2 heater voltage.

Doc

iTrader: (9)

The LC-1 does not work off of a 9v battery.

Do you have a V1 or V2?

When you hook up the LC-1 digital out via the USB to serial converter what does LogWorks "say?" - compared to what EFI Live "says?" AFR wise?

If there is a difference between the two, (analog and digital) the digital out is correct and you have a ground offset on the analog out channel that EFI Live is using.

If there is a difference you will need to use LM Programmer like you were mentioning before to command the LC-1 to put out straight dc voltages and record what EFI Live is "seeing" in the datastream.

If you have a V1 you will need to account for the offset in the calc pid for the LC-1.

If you have a V2 you will need to run the analog in ground offset routine in the scantool.

SmaknaSS

iTrader: (1)

Thanks for the reply,
I have V1 of EFI live and The LC-1 does seem to be tracking correctly. I did notice a 30 mv DC offset voltage and did notice that I had wired the LC-1 System GND(white wire) to the Analog GND(Green) on the LC-1 to the "analog common ground" on the EFI lives A/D input. I'm not sure that's where I should have terminated the LC-1's system GND(white wire)but it seemed to be the logical place to terminate the wire to prevent ground loops (should I have tied it to It's own ground?). I did notice that when I ohm tested the "analog common ground" to the car's chassis ground that I read -6 ohms, reversed the leads and read 7 ohms but there was no voltage between chassis ground and EFI lives analog ground using my Fluke 123 scope-meter. I'll disconnect the battery and check it again tomorrow.
Thank again for your input.

Drew04GTO

iTrader: (1)

How many hours of leaded gas do you have on that sensor? My daytona sensors unit that I'm pretty sure uses the same bosch sensor reccomends recalibrating every 250 hours for unleaded gasoline and replacement after 8 hours of leaded gasoline. I had my sensor go bad about a year ago and would read insanely high a/f and was never able to succesfully recal.

SmaknaSS

iTrader: (1)

Well It's starting to look like the LC-1 Controller is bad.
I have replaced the sensor.
Checked all the wiring.
Checked all grounds and the LC-1 just keeps outputting a constant 4.96Volts. Are these worthwhile to send in for repair?

Doc

iTrader: (9)

4.96 out of the analog out channels? Usually if the DAC is blown you will get zero output on the analog channels. We can fix it.

SmaknaSS

iTrader: (1)

Thanks for all your help Doc, I just went ahead and ordered a replacement LC-1 controller locally.
I may just try and fix it my self so that I have a spare. I may be able to identify the IC's in the controller and shotgun the one that logically may be bad. If I do send it to you I promise I wont send it to you all butchered up.

EDIT: I don't think there is a problem with the DAC since I was able to get in and change the output Via Laptop. Maybe there is a problem with the ADC? If It's a processor problem then forget it. I'm not going to mess with that, Especially surface mount stuff.

Bill Bowling

iTrader: (6)

How do you get the controller apart? Is it glued together?
I have one that needs repair.

Bill

SmaknaSS

iTrader: (1)

I was thinking of taking my time and carefully using a Xacto Knife. When It was time to put it back together I was going to use clear Silicon RTV.

Doc

iTrader: (9)

Careful with the knife, the rubber is thick. I use really big heat shrink to seal 'em up after I am done.

Bill Bowling

iTrader: (6)

What about using a dremel cut-off wheel? How thick is the housing?

Bill

Doc

iTrader: (9)

Use the thick cut off disc and some safety goggles! The plastic case is only about 1/16th of an inch thick. I like using a utility knife.

Bill Bowling

iTrader: (6)

How do you get this unit apart? I see the crease down the middle on each side. What about the ends and the cables? Do you leave the cables in the bottom and just cut the top off?

Thanks,
Bill

Doc

iTrader: (9)

Cut down the spine and leave the wires in tact.

SmaknaSS

iTrader: (1)

Well it looks as though the controller was bad after all. I just wired in the new controller and now everything all looking good. If this LC-1 goes bad too after a few years also I will probably not buy another one in the future unless I lean how to fix them and If Its cost effective...