cndnate

1993 Lexus Ls400
300,000 km

I have used the lexls method to retrieve the codes - lots of thanks to that fine gentleman.

Check engine code is # 25 25 - Air-fuel ratio lean malfunction

Trac code #51 - 51 - Problem in engine control system


I was thinking I might tackle the trac #51 1st since it seems to be fairly agreed that a removal of ecu and replacement of capacitors will fix, or not, this problem. Is that correct? I have replaced capacitors in my buick regal gs instrument cluster as well as capacitors in Eagle talon ECU.

Regarding Check engine #25 - I searched and saw another post with this same code
- basically the advice given was check everything.
Does anyone else have further specific information on what the lean malfunction may cause?


Car symptoms include:
- track light turns on after driving a little while (5 min, or sometimes right away) by trac light, I mean that "trac off" illuminates.

- little power at low RPM (lots of power above 3k rpm

- gas mileage is pretty good - 9.5 L per 100 km, or about 19 MPG.

- car had light throttle misfire or detonation when I purchased, since running 93 octane for 2 tanks, stumble has gone away.

- I have bought new plugs & wires and plan to replace.


Besides losing track (which is a problem with Canadian winter coming) and low rpm lack of power, car seems to behave ok.

I would rather correct his (particularly trac) before winter comes and I end up stranded.


All helpful advice accepted!

edit 1: brake light bulb light on - checking harness in trunk
edit 2: maybe I try by passing fuel pump controller to see if cures low rpm sluggish
edit 3: will visually inspect ecu

1Fast99GTP

cndnate Nice to see another GM 3800 fan I have Colorado's Fastest known GM 3800 in my 99 GTP

Anyway sorry back on topic,I am seeing the same issues with my 92 SC400 and wish someone would reply!! I have checked everything I can think of I am leaning to replacing the main O2 sensor.Snow is coming also here in Denver, if you find anything out please let me know.

DertyDOH

I have the same cel code, was told check vacuum leaks, o2 sensors and egr pipe. No vacuum leaks I can find or bad o2 sensors, seems in my experience its probably an egr pipe for me, not saying thats what yours would be too, but something to check

1Fast99GTP

Thanks man I will have to check that!

LScowboyLS

ALL LS400's have the capacitor issue, if this is not the problem in this case, it soon will be!

please use my extensive GUIDE to replacing your ECU capacitors - that way you will get the correct type and not get counterfeits, etc. and a great step-by-step guide on how to complete the repair, it's pretty easy!