TRD_Power

When I start my 95' SC400 in the morning, I get a VERY strong gas smell and it stinks up the cabin as well. I have also noticed a slight knocking sound when it is cold(possibly bad valves), The gas smell goes away after the car warms up as does the knocking. Any ideas? if it is a bad ECU, where can I get a good replacement for cheap? Lexus told me $1500! and are there any preformance computers I could use in place? the car's TPS is acting up as well so I'm wondering if the computer just needs to be tweaked some. Thanks a lot!

nasc300

mine did that just befor the HG let go completely

TRD_Power

well the car runs fine, smooth, and perfectly quiet.... if it were my HG I'm sure it would be acting a little worse than it is. also checked the oil for water and it was fine, no white smoke out of the tail pipe, no whistling.

TRD_Power

thanks for the input, anybody else?!

VJ RC51

ecu is going bad

Kaiser

iTrader: (1)

Head gasket makes a lot more sense than the ECU.

VJ RC51

When my ECU started going bad, when the engine was cold, like sat for 6hrs, when you started it up, it would run horribly rough, and run ultra rich. If you let it warm up for a few mins, it would run fine. It did that story for about 2 months, then started doing it all the time. I replaced everything, fuel injectors, compression test, fuel pump, mass air, bypassed fuel ecu.. and all it was.. was a bad ECU. It never thru a code or hinted it was bad, but i swapped it out for another one, the car ran perfect, all the time. Our ECU's go bad all the time, the caps tend to leak. Getting another used one is hit or miss, ppl never tell the truth. It took me buying 2 of em to get one that worked good. At least u can get em for $50-75 bux.

AURELIOMK3

well do you have any check engine lights on cause you may want to check those first second do a compression test on each cylinder, does not take much and you can find out if it is a head gasket or not. your going to have to pin point your problem and eliminate certain questions good luck though

VJ RC51

It will not always throw check engine lights... Well a big hint when mine went bad, it would not throw or store one for anything except air temp sensor. I could unplug o2 sensors, etc, and it would not affect the engine, its running condtion, or throw a light.

AEMxRACER

I was told a bad cmashaft power sensor shortcircuited my ECU....the dealer told me thats probably not true and the ECU was bad all along, in any case....i get the impression reading the forums that the car will still run, albeit poorly, if the ECU is bad....can I pick my car up from the shop and drive it for a few days until I can get the new ECU in? Is it difficult to replace by oneself?

Also, I was looking on Ebay and the ECU for the 1UZ-FE (thats the 93 V8 SC400 right?) is like 120$.....where can you get it for cheaper and what do you have to be wary of when buying a recycled ECU

Dont hate, lol, Im a noob- any help would be much appreciated. thank you for your patience

AEMxRACER

TRD- lexus told me the same thing.....1400 to replace the computer, im thinking about getting one off the internet and trying it myself....did you ever solve your problem?

bangdangvn

^ I'm sure you can pick one up at the local yard for cheaper than 120, SC's are rare in colorado and they wanted 70 for it here...atleast for the sc300.

AEMxRACER

I got my car back from the shop today after the ECU rebuild...and it seems like theres something with the acceleration, i have to literally like FLOOR the pedal to get the engine over like 2500 RPMS, and ive started getting a strong smell of gas when i start the car/ move it out of P- but there are no leaks, no fluids underneath the car.....the other thing is this light just popped on the in the cluster, its right above where the 2 is on the tach (lol, forgive the crude description) and its like the outline of the car from overhead with these 3 lines pointing downward from each side of the back....i thought maybe it had to do with the brake lights but they seem to be working fine....any idea what the light indicates?

TRD_Power

Hey I never did solve the problem because I just kinda gave up on the car, haha. Kinda funny because I found this thread of mine again today and now I am determined to replace the dang thing since it set off the gas alarm thingy in my house after starting it up. I'll let you know if I get to the bottom of this. Thanks, all!

sc250tt

i had the same problem with my 1j and a couple sc and gs 400, it turned out it was the ecu.