The boys are back in town.

[robbie.hamilton]

We got to the bottom of it after many hours of head scratching and tests we have her running. It turns out the air mass meter was broken and we unpluged it and she runs like a true lexus should. We are putting her back together this evening and tomorrow evening so will take some pics.

[cyclone]

WHOOOHOOOO knew you could do it:))

[lesman01]

that's awesome! what the heck is an air mass meter?

[robbie.hamilton]

Its a thermostat that controls the mixture of petrol needed in the engine depending on the temperature of the air being sucked in through the air filter. You will see it pluged in to the air filter.
We have one more day of work on the boat and she is ready for her first water test in about two years. Really looking forward to it. Will post pics of the boat soon.

[jonwadkins]

Not to get technical but..... to my knowledge the air mas sensor is not used for the temperature of the air.  It is used to determine how much air is coming into the engine.  While it may also sense the air temperature its main function is to determine how much air is coming in.  This information is sent to the engine computer and the computer then instructs the fuel injector on how much fuel (petrol) to inject.  The computer also is looking at the engine temperature to determine if extra fuel (a richer fuel air mixture) is needed (ie choke from the old days) when the engine is cold.  All engines need the same basic fuel air ratio called stoichiometric combustion.  The ratio is 14.7 parts air and 1 part fuel.

In the old days and still today on some of the GM marine engines the air going through the carb creates a venturi affect to then suck the right amount of fuel through the jets, into the carb and on into the engine.

I know you all are saying 

On fuel injected engines, ie the Lexus in the Epic boats, it works kind of like this.  You advance the throttle, opening the throttle body right next to the intake manifold.  The engine sucks more air in, the mass air senses this, the computer instructs the fuel injectors to inject more fuel which results in engine running at a faster RPM. 

My question is how in the world did you trouble shoot the mass air sensor.   I don't think I ever would have figured that one out.  Awesome Job!!

[wakejunky]

technically all a fuel injected engine needs to run is a rpm signal. If you want it to do more than idle it needs a load sensor (mass air flow-MAF used on most if not all late model vehicles, manifold absolute pressure MAP, vane air flow-, and Karman vortex air flow meter) Toyota and Lexus has used at least one form of each on their vehicles over the past 18 years. All other sensors simply fine tune the air fuel ratio. The reason unplugging the sensor made it run for them was it was defective and feeding the computer a false signal, when they unplugged it the computer was then able to use the rpm input and apply it to its basic calibration tables and estimate a load signal.
All MAF sensors used today incorporate the air temp sensor into the MAF sensor. Again the air temp signal is only used to fine tune the air fuel ratio.
When Toyota/Lexus decided to install the 160 degree thermostat in our engines they were able to keep the engine in full power fuel enrichment ratio of 12.4 to 1. (I would bet that is one of the main reasons our engines foul spark plugs so often, yet the automotive version almost never fouls plugs.)Instead of the 14.7 to 1 that our cars want to achieve. When you see aftermarket companies selling computer chips to optimize power they sometimes include a 160 degree thermostat, which keeps the engine from reaching full operating temp, and leaves it in that 12.4 to 1 region. In order to produce the most power (JET chips comes to mind). Sad to say its usually the $20 dollar thermostat that helps produce the power not their computer chip with their version of basic fuel calibration tables. SO don't waste your money on a chip just buy a thermostat and then prepare for your engine to loose some fuel economy in exchange for a little more power.

Now thats some useless info

[robbie.hamilton]

We have spent all winter pulling the boat apart and trying every thing imaginable. We had a guy down only the other week in the garage and he said give me a look at your boat. he jumped up and got Jeff to start it and gave the throttle loads of movement and for the first time it ran and then cut out.
That lifted the spirits. I Was down the following weekend and Jeff should me what he did and then he unplugged the Air mass meter and it ran we were both shocked and delighted it was the first time we had to turn the key to shut it off. So i guess after all the test and check eventually we would have found it but thank god we did. We have it about 99% back together and the new sound system in. I will take pics next week before we take her down for her maiden trip. Will keep you all posted.

[Bitzco]

I already knew all that air mass sensor/temperature/fuel mixture stuff. My 82 Yugo has all that sweet technology. No more advanced car has ever been made. For that matter so do my Pacer and Gremlin. I coulda figured that out for you in a second.