Ok i have a 93 SC300 NA-T and i drove it today and the car runs fine at idle,no problems..but when im driving it jerks when i let off the clutch unless i have it at about 2500RPMs but the worst thing is when im driving on the road if i dont push the gas to about 30% it will jerk also and the biggest thing is when i start to get to 3k RPMs it starts to spit and sputter like its running out of gas so i only have a small pedal space that is will drive good...Im running a apexi safc and the TPS seems to be set right when i check with the safc..I was thinking it was a boost leak but i took the charger pipe off so it was like N/A and it stops backfiring and spiting but at the same 3k RPMs its like the car hits a wall and cant get it passed 3k......it has stock temp plugs but i dont think that would make it run so bad and the fuel is at 42psi so i dont think its the but i may be wrong...timing,tps,fuel????i would be thankful for any help

 

BTW if the car is not in gear it will rev all the way to redline with no problem..Its just when its under load..

 

anyone????

 

Its either a air leak or air metering problem.

 

Check vacuum leaks, ignition system and fuel pressure and volume.

 

Is 42 psi too low? Shouldn't you be at above 50 psi? I dunno, but for a NA+T, I thought you'd need more than 42...

 

42 is fine under no load u might have had an ecu take a crap on you try to get ahold of a good one and swap it. Happened to me. Gl with fix

 

Ok i got some new plugs today because a cool club member told me that is maybe that..Right now i have stock plugs gapped @44....So i was looking for some NGK 3330 but no one has them...I got some NGK 5553 (BKR6ES-11) and gapped them to 27 and i hope it will fix the problem...

 

It does sound like the ecu has crapped on you bro!

 

Ok sigh,,,changed the plugs and it kinda made it worse.Now it does it while free reving...but now i can SHOW you what its doing....What you see in the video is how it feels when im driving..

 

Its like a antilag or something....Fuel is @42psi, injector are the stock ones and Apexi SAFC is set at 0 all the way across...

 

...............

 

Reving like it's hitting a brick wall? I had that problem until I changed out the ecu.

 

really?lol or make more problems...Im not letting this thing beat me..

 

Ok,i started messing with it today and ADV the timing about +10 and unpluged the SAFC and it ran 90% better but it seems like when i get into boost sometime (alot less) it bogs down and when it does,it goes from rich to lean very fast and that is when it putters...Im thinking the fuel-pump is going out or the ebay FPR and not acting right..