pacerdonfl

Hi - thanks for looking. Car starts, runs and idles perfectly....but after a certain amount of time (variable, but usually between 10 and 30 minutes) it just loses power and eventually stalls. I can usually start it right back up and runs nicely, but will stall again within 30 seconds or 5 minutes...

It will usually run nicely longer when starting from cold.

I have replaced the fuel pump resistor with a good one - still stalls. No check engine light and don't know how to check "codes"....

Any ideas would be appreciated. Car has 140,000 miles and got a dealer 100,000 mile service.

I have searched the forums for similar, that's when I swapped the fuel pump resistor.....

Thanks very much!

/Don

oldskewel

iTrader: (1)

Fuel filter?

dicer

I have one with that problem too, still in the process of fooling with it. Also have read about others with the problem, I sure hope one of us can sort it out. I wonder what happened to Magda she was dealing with this too.

Fuel filter? They run at more throttle and just won't idle, and would also pump out some unburnt fuel in the exhaust, I think fuel delivery is okay. Its either a fuel metering deal or air metering deal.
Does anyone know how long it takes for an old Gen 1 to go closed loop?
And others that have had the problem the ecu fix does not fix it.
So when I can I need to check o2 voltages and I suppose do a fuel pressure test too along with an ECT change.

Braxton33

I have had this problem and what fixed it for me was changing the mass air flow sensor

dicer

Funny you mention that, I did get a code for that. I just removed it and checked values. I guess I'll change it and see if that fixes it.

And where did you get it?

Lucky they are dirt cheap, he he he,
http://www.oemlexusparts.com/lexus-1...-sensor-30461/

Rmmccarthy

I noticed this thread and I am having similar issues car runs like a dream then cuts off like I turned the key no sputter or rough idle. I got codes 14 ignition 1 and 24 intake air temp (MAF) I am wondering if anyone knows about open and closed loop. how can it run so good cold open loop and die when it hits closed loop I have an igniter testing bad BUT.... the car runs so good weird any way I will keep yall posted with results any and all input appreciated. Thanks
Rick

dicer

I have been wondering how long before they go into closed loop? That would mean things like airmeter and o2 sensor.

sndlight

According to my UltraGauge my 2nd Gen takes 1 minute maximum to get into closed loop when outside temps are below freezing and my coolant temp is around 25 degrees F.

The first thing I would do is scope it or hook t up to an advanced scantool to see exactly what signal you are losing - if you are losing spark. These motors will not run if they do not see oil pressure and either cam or crank sensors (I can't remember which). I believe it cuts fuel if there is no oil pressure and cuts spark if there is no cam/crank position signal.

If there is faulty MAF or O2 data the computer will go into limp mode, not exactly shut down.

dicer

Obd1 won't do anygood to use an advanced scan tool, I don't think there is much to see with it. Mine just won't idle good and dies out, keep rpms up it will run somewhat. I don't think its a spark thing.

Yamae

For those newer LS400s that have 4 of 4 wire O2 sensors, it needs less than a minutes to get into the closed loop because those built-in heaters make it possible to do so. O2 sensors need the temperature at least about 530 ℃ to generate the enough voltage.
On the other hand, for earlier models that don't have heated O2 sensors, it need a few to several minutes to get into it depending on the condition because the exhaust gas is the only source to heat the O2 sensor up.

oldskewel

iTrader: (1)

I'm not so sure you have the same problem as the OP:
"loses power and eventually stalls" (OP)
vs.
"cuts off like I turned the key" (you)

You might have the same problem, but more likely not. To me, the first one sounds fuel related, the second one sounds electrical / ECU.

pacerdonfl

Thanks for all the reposnses! Yesterday I started it and ran it at idle for 45 minutes, then ran it up to 2000 rpm for about 3 minutes (parked) - ran beautifully.
Guess I'll replace the fuel filter today and take if for a drive??? Maybe it need more load than idle in the driveway.

/Don

pacerdonfl

I replaced the fuel filter yesterday - wasn't the problem. I then drove it about 25 minutes yesterday - ran like a top!
Drove it to the park this morning (10 minutes) ....all fine. 2 hrs later coming home, after about 3-4 miles, it again started losing power and going down to 200 rpm....with no response from gas pedal, then intermittently coming back to power for a few seconds, stalling again, then back to power. At one point it stalled completely. I restarted it and it came right up sweetly and took me the 3 blocks to home?????Arrrghhhhhhh.....

Rmmccarthy

I searched and searched I had a code 14 i checked ignitets I replaced a coil I found the problem there was a 2 wire connected near diagnostic connector it was a white/blue and a black/ Orange these are on the igniter 1 circuit it was a broken bad connection that would kill ignition when vibrate or warm and expand hope this helps others I am thrilled and have many more projects to go glad I did the ecu though so I know it's good

pacerdonfl

Thank you for the response - could you help me more and be a little more specific about where the white/blue and black/orange connector is?

Thank you!