So I got in my car earlier today and went to start it as I usually do, but everytime I went to start it, it died immediately. So I starting giving it some gas as I was cranking the ignition and it started, but the car was sputtering to stay started. I also noticed that the RPMs were extremely low (like 300-400 RPMs max), to the point where the car was shaking pretty hard. I tried taking it for a ride up the street from where I live and it died on me at the top of the street. So I finally got it restarted and continued to keep revving/driving it and this all finally stopped. I noticed the check engine light was coming on before the motor would stall though if that helps. I know this could be a variety of things, but is there anyway it could be an O2 sensor?

 

Your MAF could be dirty. Do you have an after market filter or intake setup? **DONT USE MAF CLEANER TO CLEAN IT** USED A COMPRESSED AIR CAN TO BLOW DIRT AWAY with a compressor or compressed air can**

 

It is probably the fuel pump ECU. My car was doing that for six months until I did the 12V fuel mod. Here is a link on how to do it: https://www.clublexus.com/forums/per...tures-faq.html.

 

^These guys both have good advise...It sounds MAF or fuel related, and my guess is leaning more towards fuel....check your codes and let us know what code it's throwing.

 

Yeah I don't have a OBD-I scanner and I was told on another thread that with OBD-I you need to get the Lexus dealer to check the log files if the light comes on and goes off from time to time. Because sometimes my CEL comes on and then goes away randomly as I continue to drive. Also, I am using the K&N drop in filter for my SC. How do I clean the MAF sensor? I've been meaning to do that. Where is it located? Is it the silver box looking thing on the stock airbox tube that goes to the throttle body? My 94 SC300 only has 130K miles on it, so is it possible the fuel pump is going bad? Also, it was EXTREMELY hot here yesterday, like 100 degrees literally and we rarely get that kind of weather around here. Is there a chance the heat/humidity had something to do with it? I just got all my fluids done about a month ago or so, so the car can't be over heating because the water pump/timing belt/etc (notorious SC fixes) have already been done before. By the way, how much performance boost are we looking at if the MAF sensor has never been cleaned on my SC?

 

The MAF is the black box with the three screws holding it down on the "silver box looking thing" as you descirbed it

 

Did you recently gas up? Maybe you got some bad gas with water in the tank and now its flushed through.

 

Question on this- did the standard FP bypass not work? (like the jumper in the diag box?) Curious as to your symptoms with some issues I'm having right now.

 

I only tried the one in the link. A few of the symptoms were the car would stall right after I would start it and then the car would shake as it died. It usually took about six tries to get it to start. Sometimes it would just die while I was driving in the street or on the highway. It went away for a while and then one day when I was having some car audio work at a local shop done, it kept dying and wouldn't start so I had to have my friend at the shop do the fuel mod in the parking lot. When the car would die, a check engine light would come on too. I never got it checked because it never died during the two weeks the dealership had it a few months prior.

 

Hmm well I'll give it a shot. Doing the jumper bypass hasn't made a difference, but maybe the full on 12v will

 

It should work! Hopefully it does! It really sucked having the car cut out in the middle of traffic. I probably would have sold the car if I didn't know about the 12v fuel mod.

 

Considering it only took 5 minutes to do I guess it was worth it- however it had the exact same function as connecting the FP an B+ jumper in the diag port . But yeah my car still died after idling for about 6 minutes :/

 

First things first check your codes.

My car was stalling out on me mid drive and giving me trouble starting at times, my problem seems to be a tps problem for the efi.

You may want to check your tps also as the problem sounds similar.

 

my truck did this. guys at autozone told me it was my EGR valve, i never got a chance to replace it. due to the fact my engine blew after 102,000miles... hhm but yea check your egr valve and somebody said something about the catalytic converter?. doesnt make sense to me, anyone that can clarify?

 

Hey, you finally made an account! Did you get an SC yet?


That sounds like a lot of work. I don't know too much about that kind of stuff since I'm more of an electronics guy. The fuel pump ECU is most likely what's wrong the SC though.