I picked up a 92 sc300 not to long ago and Friday ran into a problem. The check engine light was on ever since I got the car (for an o2 sensor)but the car ran fine.
Friday I left for work and was very hesitant for a few min on idle but went away.I went to a few stores and each time I started it up encountered the same problem.I didnt drive it nor have time to work on/look at the car this weekend but when I went to start the car this morning it started then died.I restarted it and it idles really rough and is really hesitant.I give it gas and the idle drops before it goes up just sitting in the driveway.


Im thinking a bad ecu? Anyone else had this problem or seen it before?

 

try checking all the vacuums for any leaks, also check ur intake and make sure its not lose

 

i had similar problems, check your fuel ecu. there is a thread on here about how to test the power. GL

 

There was one vacum line i found unplugged. I pluged it back and disconected the battery for an hour and had the same results when i re started it. am i resetting the ecu wrong?

The car had the 12v fuel pump mod when i got it, shouldnt that bypass the fuel ecu?

 

Anyone else have any insight into this problem?

 

MAF sensor...

what happens if you put it in "D"?? could also be TPS/IAC sesnor??

 

Its 5 speed.....

 

im on my 3rd ecu and still have the problem.

 

Car no idles weird. It does how ever backfire and bog under acceleration. I noticed while it was running the EFI relay getting hot so Im going to replace that tomorrow.I still have the same thing with the check engine light though.

Any other suggestions would be appreciated.

 

I think i have pin pointed the problem to the maf. When plugged in the car wont rev but when unplugged the check engine light throws the code for being unplugged and it will rev and idle normal. Just ordered an maf so ill post up if that fixes the problem.

 

A buddy of mine is haveing Hessitation issues and the car ( Sc400) has stalled on him 3 times now. I asked him to check if the fuel pump is priming and said yes.

I'm guessing that he has the same or similar issue as you. Does anyone know if the MAF sensors are interchangabe between the Sc300 and 400 ?? They look like they will but not sure. Thanks

I hope that is the issue with your Vehicle I understand the headackes and stress these things cause. Please keep us posted.

 

Yes they are interchangeable from 92-95.

 

Update: finally fixed the problem.Replaced the maf with no luck so today I bought a new tps sensor and that fixed the problem. Just need to find the calibration settings for it.If anyone knows them please post.Thanks.