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Hi I just got this 1992 lexus sc400 2 weeks ago from a neighbor that she had it since new, it has 159500 miles on it but really if there is such thing as gentle miles this is it always caraged,old lady,all maintenance done and receipt,timimg belt just been replaced within 5000 miles new rear tires,just passed the smog test very easy ..
did not want another classic car having been tourched by my last one 1986 190e 16v 2.3l
in short I couldn't pass on this one.so I was looking for a sc forum this one looks the best and with very knowledgeable people.i have a question just took a trip from long beach to camarillo and I was very surprised how smooth and quite it is this is my first lexus btw..so 80 miles to go 80 miles to come back everything worked as advertised in traffic ac ice cold ...except on the way back at my last exit few yards before stop sign slowing down for a full stop the car just died inexplicably put it in park start right up 2 miles down the road again slow dawn to a stop car died again,back in park and start right up again.and no idea why.
Car always start right away idle is pretty steady can't figure it out any one could help with an suggestion what to look for will be great.tnx
Mimo.
No i did not notice any light to come up before it died,i am thinking something to do with fuel delivery i was cruising for 80 miles on the freeway like 70mph and at the exit when i slowed down to like rolling speed just died.then started right up.
Fuel delivery or air/fuel ratio sounds right to me, too. You might look up the fuel pump ecu bypass stuff and try jumpering the diagnostic box pins to see if keeping the pump running at full speed prevents it from happening. I wouldn't think ignition system stuff (coils/rotors) would tie in to happening when you slow down. Couldn't hurt to check the air intake and vacuum hoses for dry rot and/or leaks, and make sure the throttle body isn't sticking from gunk.
I would honestly just do the 12v ECU mod and forget about it. The fuel pump ECU doesn't really do much to this car and is a weak point that can easily be bypassed. Just search 12v Fuel Pump and you should find the thread. It's one of the easiest mods and the DIY thread has lots of pictures.
If the problem persists, then definitely check the ignition system and all the vacuum hoses like t2d2 said.
My car normally runs just fine. A/C off, everything's fine. Put on A/C and it speeds up a little as normal.
If I then shut off my air conditioning, the idle goes really low and the engine stalls when I come to a stop. Start it up again and all is well. Did you by chance shut off the A/C on the highway before stopping?
It will help with stalling issues at idle, and it'll be especially noticeable if you have a dirty IACV when the engine is cold, and when you apply loads or remove loads from the drive belt... like AC, or turning the steering wheel at low speeds or a stand-still, or holding down the window up/down button when idling.
OP, I'd do the 12v fuel mod as it's easier, it doesn't sound like it's an IACV problem for you OP, but it's definitely something to check if the problem persists.
10-01-14, 10:33 AM
newbie with some questions
