1999 LS400 check engine error codes in display

[G.O.]

Greetings, here comes my first post! 

A 'check engine' message has recently appeared on my display. As this car refuses to communicate with my OBD2 scanner  I bridge the "OBD2" or DLC port to view fault codes on the dashboard display. 

I am seeing: EFI___NG, which quickly  changes to EFI ___E.  Scrolling through the codes via my steering wheel buttons I get two more codes: VSC___OK, and CRUISE CONTROL____.  

Can anyone enlighten me as to what the  EFI___E fault code refers to?  The Lexus and Toyota fault code charts I have found all have multiple letters and numbers attached.

Any help would be appreciated as the old girl has lost quite a bit of power, shifts erratically and guzzles 22L/100km as opposed to 14L/100km.

Thank you.

[BigBoomer]

The LS400 "OBD2" is not standard OBD2 so mostly does not work with standard OBD2 scanners.

This thread may help, especially Dan D's comment near the bottom.

 

[G.O.]

Thank you BigBoomer.

After having a some resistors replaced on the ECU I now get the check engine light only if I accelerate hard to over 3 or 4K rpm or drive over 102kph.  Having said that, the car pulls much better and the shifting nearly spot on. The display error code has changed to: EFI____E____NG____12.  Googling error code 12 pointed mainly towards cam or crank position sensor issues.  Resistance check on these all showed them to be well within specs.  Cables are a bit hard after 25 years of heat cycles but not broken, connectors are all new. I have new sensors ready to install but these are  non-OEM items so I'll only install them until I rule out other issues. First I intend to replace the ACIS vacuum solenoid which is well and truly fried.  A new OEM one is on it's way as is a new MAF meter which I suspect might be tired after 300K+.  I'm hoping that replacing  those two items will again bring improvement.

Any information on code 12 or feedback from others who have tackled similar issues are greatly appreciated.

 

 

 

[steve2006]

Resistors? It’s normally the capacitors which cause the ECU problems.

[G.O.]

I had all the capacitors replaced 10 years ago as a precaution.  I checked the ECU circuit board before re-installing it after this recent work and discovered a resistor that had been replaced as the solder joints weren't the 'perfect' factory shape.  This work has made a difference as the check engine light error code changed and the throttle response and shifting points are almost back to normal.  Today the check engine light hasn't gone on during hard acceleration.  Great!  I'm going on a motorway tomorrow so I'll get to see if the annoying beep and engine light go on when exceeding 102kph.