My 1992 sc300 has been going through plenty of problems lately. It all started with the turn on and then it flooded and turned off when cold. Then I purchased a new ECU and that stopped the fuel system being on constantly but still no start so I did plugs and wires, same outcome no start as if it was flooded So I unplugged the fuel injectors and it started right up and burned off the fuel. Then my friend told me about the coolant sensor. I replaced that and the car No longer floods itself but now When I start the car it comes on then sputters and dies unless i stay on the gas and it runs terribly still. I then unplugged the Maf to see if that was the problem and it ran worse and barely started so i cleaned it and then I tried the TPS and unplugged that. The idle was even more horrible. So now Im thinking there's something wrong with my fuel system or maybe I have to do the 12V fuel pump mod.

 

Welcome to the forum . Since you are new to our forum , I am moving this to the Performance & Maintenance instead of deleting it .

I would suggest do a lot of reading and familiarize yourself with the forum rules and what is written on the stickied threads on the main SC page.

Good Luck !

 

Oh I apologize for this and thanks!!

 

***Update*** Tried to do the 12V mod and it was already done. Really don't know what else to check. Everything is replaced and I went through the Sticky looking for idea's. I also tried searching old post for the same problem but all of the old post says to check the ECU or do a 12V mod. Iv'e swapped between 2 ECU's and both the same response just really rough idle and instant stall

 

The coolant sensor has nothing to do with the injectors flooding your cylinders. From a cold start , even if you unplug that sensor , a good running car will start because the ECU will go into a mode assuming that the sensor is bad so it will start the car. It is mostly needed on a hot start meaning when the engine is warm. It needs that coolant sensor.

If it floods the cylinder , then you know there is nothing wrong on the fuel system (pump) since there is fuel delivery . That means with or without the 12v mod , your problem is not on that area.

The info / diagnostics you mentioned above is all over the place . Some stuff you mentioned has no relation with one or another problem . So the last info I read is the car starts but idle is bad .. is that right ? I assume the car stays running now ,it is not being flooded and it is just running poorly ?

That can be a lot of things ..make sure fuel filter is clean just to make sure you have a good fuel delivery . I assume it is clean since you were flooding the cylinders. Now check the plugs , coil and distributor.

And where did you get your 2nd ECU ? Was it guaranteed to be in good working condition ?

 

Thanks for the reply! I actually looked into it farther and the 2nd ecu was repaired by driftmotion so it's in good working order like my first one but we seen there was a little gash on the timing belt! I decided to advance the timing and the idle got a little better and I was able to put it in drive and the car didn't bog out or die under load! I'm deciding to get a timing light and see if it jumped timing because if that's the case it explains so much.