Sputtering & stalling issue... won't stay running!!!
 

Hello everyone, sorry for being so thorough, I just wanted to put everything out there. Anyways here we go... let me start off saying I'm fairly mechanically inclined. I fell in love with the scXXX's 6 months ago and bought about a week ago a 1993 sc400 with 151,XXX miles on it. When I bought it I could not get the car to run for more then 3 seconds... its just start sputter sputter stall (3-5 sec.)... try to give gas and it just stalls faster. Previous owner was told that by the mechanic that it was the mass airflow sensor.... $800. So I towed it home bought a used mass air flow sensor for $40.. while waiting for the part I washed the motor as I've done with other cars a thousand times (I know I know, but keep reading) Everything is looking clean and I'm excited. Part gets here... it started up fine ran for 15-20 mins in the driveway... I cut it off and walked away chest high. Next morning back to start sputter sputter stall.... same thing. Went and picked up some water remover and about 8 gallons of gas... no fix. So now I replace plugs wires caps and rotors and fuel filter. upon going into the spark plug well for the plugs I see that water was in there... I feel stupid instantly. Soaked up as much as I could... removed plugs and cranked, shooting anything that dropped in... out. However no fix same exact issues. So now I got my hopes set on Fuel. So next I tried the 12v fuel pump mod. Mod worked but did not fix problem. So by now I hear the fuel pump coming on easy cus the rear seat is out. So by now I'm confident about the fuel system being good cus the exhaust is also smelling a little rich. Coincidentally Next day comes my cheap intake... I know I know BFI, but the flexible rubber part of the oem intake was very dry rotted and if you covered the end and held it to your face lol you can suck air right through it. I also like the look and sound... anyway after replacing the old intake with the new it immediately fires right up... runs fine.. even giving it gas, that is until it warms up. After it warms up it will try to stall if you give it gas... If you let it idle it will idle for a while but then just stall out as a result of an increasingly more frequent miss-fire as it gets warmer. Now after it stalls... 30% of the time it wont even try to cut on it will just crank. At this point I check and there is no spark at cylinder # 1,2,6, and 7 (no rhyme or reason why those particular cylinders) and I've got no spark. So by now I figure out not to use the port under the hood... but to use the one that I found popped out of place tucked behind the dash for the obd1 jumper thing. Now I noticed this yesterday... when its running sputtering check engine light is flashing. But when it shuts off and I try to start it again and it wont do anything but crank, I noticed that the check engine light is not there while the key is in acc. I mean... should I be sending off my ecu? I've searched what I could and am just desperate looking for input cus I've got a new inanimate object as a best friend that's sick... and she just wants to ride. My wife's got an rsx with a 100 shot and been talking crap. I said "honey there is just some stuff in this marriage your going to have to deal with, one being that yes I have a mistress... she in the driveway with syphilis right now, but Id still choose her over you and your Honda any day. Once this gay marriage thing gets settled I'm bringing the car marriage thing to the table and honey... we through" lol let me stop. but yeah any advice would be greatly appreciated. Thanks First Post sorry for the length of it but I think I got everything.

That's a lot to pack into your first post, but few people make it through a paragraph that big.

Might wanna check the coil packs. The SC400 has two of them. They go out often with these older cars.

Test them by unplugging them individually at a time. If the car stalls or runs worse, the coil is doing it's job. If the car doesn't change when you unplug the coil, it needs to be replaced. There is one on the drivers and passengers side.

I know... lol. trust me, I'm not new to forums either. After I finished typing... I looked at it and was like :egads: nobody is gonna read this. But I wanted to lay out all the facts in case anyone had any questions.

I have coil packs coming in the mail. But they both go from "cold start" both firing fine til it warms up then a random misfire... then turn key off and back on and I get no spark from either just cranks until I take the key out for awhile and come back. when I'm getting no spark I also have no check engine light when the key is in acc. doesn't that mean I have a ecu problem?

If you suspect ECU stuff, take a look at this thread:

https://www.clublexus.com/forums/ls4...capacitor.html

I have my new capacitors being installed today.

....or just a bad bulb...idk why people say that points to the ecu. My 92 has no cel, and a rebuilt ecu. Never has worked. Though, the ecu is a great place to start. Don't buy a used ecu. Rebuild or new. Buying a used one will prove to create a difficult troubleshooting guide.

No, my check engine light works fine until I get no spark which happens after I get to about normal running temp.

Then you answered your own question. Replace the ecu and report back what happens.

After replacing the sensor you have to drive some for the computer to register it.