1990 Ls400 Off&on Engine Code #25

[Dre od DC]

So my 90 LS400 is having this off and on engine code #25 (Air fuel lean malfunction). It's sometimey though.. <_< .. sometime it comes on and then goes off..i drive 40 miles and it off.. then drive back and it come on like the last 10 miles then get home and go somewhere in the am it goes away after the warm up..

Anyone have any suggestion on how to do away with this.... i'm leaning towards a new fuel filter first.. but any suggest is most welcomed!!

UPdate* OK So the Check Engine Code hasnt rear'd it ugly head... But a new Development... Just got home.. and the damn car damn near give me a heart attack/.... all the dash light came on except "the check Engine" and it came on for like 5 sec and then go away did it twice....

Someone lend me a hand here...

[steve2006]

Hi,

Normal cause of all dash lights coming on is the alternator on it's way out so have it tested as for the code25 check for air leaks on the induction particularly all the vacum pipes or possibly a sticky EGR valve allowing too much exhaust gas into the inlet manifold

[TA in KC]

Code 25=Oxygen sensors.