Lexus LS400 Engine Cutting Out

[J68]

I have a problem with a 1998 LS400 - its has been off the road for a while as the alternator had failed.  This has now been replaced and appears to be working fine when the car starts.  The car runs for around 10 minutes and then cuts out - the Battery voltage drops just before cut out from initially around 14.6v to less than 13v.  The car will not then restart until it has cooled down completely.

Has anyone had any similar issues?

[Supafly]

When it's warm and cuts out, is there still fuel pressure in the system?

Does it fire right up when cold or does it need to crank for a while first?

[steve2006]

Hi John and welcome to the LOC.

Any live or stored fault codes?
Reason I ask is that there are multiple causes, favourite for thermal failure I.e. when it gets hot is the CPS but then it could be the notorious ECU capacitors, fuel pump as mentioned by Supafly, MAF…the list goes on.

You really need a fault code first, guessing and replacement is the most expensive method of fault finding.