dumping raw fuel

[itsmejim]

Have a '96 ls400. Have spent big$ to have scans, compression test, leak down tests, etc. Car will run good for a while, then rough and check engine light and misfires set. Shows 6 of 8 cylinders and a cylinder with low compression. 175,00 miles. Last was finalized as "white smoke" but have now found this is smoke from raw fuel being dumped  and, of course, really rough and have decided to have a 2nd opinion, can't accept that the first expensive scan an tests were deemed terminal. Bought the car used, with 152,00 miles with very few issues. Watched my latest choice of tech read a scanner in real time and it shows the change as the injectors fire. The list of P300 codes is all that has shown up so far, broad area, right?

If anyone out there has had any experiences relating to my current problem, please pass along what happened  if it in any way resembles this condition and what course or cure  you came up with. I hope this is enough basic info but am prepared to try on more in detail, my problem. Again, just can't accept  the word "terminal" with this auto.  All this came out of nowhere and I need some good ideas and starting points if yu can help, thanks in advance.

[Exhaustgases]

First I would have really liked for you to post the details of the scans and what the "LOW" compression reading was.  There are 3 main things I can think of right off that will cause that problem you have. And they are not in order, 1 Low compression, 2 leaking injector especially the cold start injector 3 the ecu

And not knowing your Low compression reading cylinder, my first bet is the ecu. I have had that same problem before on some non lexus cars and truck and it was the ecu that was the cause.

This link should show you how common the ecu  problems are.

http://www.clublexus.com/forums/ls-1st-and-2nd-gen-1990-2000/656360-all-my-crazy-lexus-issues-solved-ecu-leaking-capacitor.html

And this ecu fix is only about $10 or so depending on who does it.  Don't give up on the car, you could have these same problems on any car newer than 1980 or so. Its just the fun of having computers in cars.