Hi there...

I have problem getting the engine in closed loop mode.
After I installed headers I tought that it was because temperature so I got a wideband instead since I was going to tune the engine also.

Still the engine shows open loop mode in TunerPRO.
I have done some modifications to the engine so I needed to tune the MAF tables and the Timing Advance table a little bit.

Anyone knows what could cause this??..I guess it just have to be something with the tuning.

It is a 305 MAF engine tuned with 6E in TunerPRO.

 

can you post a tunerpro .csv log? it's hard for anybody to just guess.

 

Did you change the temp to go into
closed loop

 

I post one now so you can have a look. This is a week old trip though so I have done some small tuning mods since that time also.
I know the TPS isn't correct so that is adjusted and I have also leaned out some of the MAF tables.
Anyway, please take a look. It is compressed in ZIP format.

Yes I did change the temp. I think I changed it to about 120 degrees.

 

Your o2 sensor isn't doing what it needs to for the PCM. Look at column Q. It should be bouncing from like 850mv down to maybe 200 with very high frequency, but it's floating at a near-constant 450mv.

You don't want a wideband o2 for the PCM to use, just get a 4-wire sensor (heated). Wire the heater element to the fuel pump hot wire, oil pressure switch, or the ignition circuit. Fuse&relay is good, but not required.

Delphi ES20317 is $42 on amazon. The proper connector can be found on 96+ chevy trucks (4.3/5.7), and probably a range of other vehicles.

 

I have the wideband Lc1 kit and that wideband sensor works like a narrow band sensor to the ECM if I connect it correctly.
Other than that the wideband sensor is working perfect on my AFR gauge.

Could this fault mayby come from a short to ground or something like that?

 

From the data log it actually looks like the sensor is disconnected. Usually, even with the sensor downstream it will wake up once the vehicle is being driven.

RBob.

 

Sounds like the same to me actually. But I don't understand why because everything is wired up correctly. I connected the LC1 as the instructions told and that wideband works perfect. And the instructions told that if I wanted to connect the wideband to a PCM I could connect the brown wire to the 1-wire output for the sensor from the ECM. So I cut the D7 wire at my stock 165 ECM and connected the brown wire to that pin.

I think I have to check that all the ground are connected correct.

 

Double check the programming of the LC-1 itself.
Might be the cause of the alternate output not doing what you think.