My 93 sc 400 is having issues with a 2k rpm rev limit and the only codes being thrown are for the tps and egr system, I’ve heard the ecus go out so I’ve replaced mine 3 times with used computers and have continued to get a dysfunctional vehicle, have I gotten 3 bad ecus or is something deeper going on that I’m not seeing? Possable wiring issues that keep blowing the computer?

 

It's possible a bunch of used ECU's would all be bad, but highly unlikely they would all have the exact same faults, considering how wide ranging the symptoms of ECU failure are. So, I would assume your TPS and EGR actually do need inspection.

 

I know it has an egr delete so that is understandable but could the tps really cause a limp mode running condition?

 

I wouldn't think so, but it's pointless to chase hypotheticals until dealing with the known issue.

I also don't think that's limp mode. Limp mode throttles power at any pedal position, rather than just capping RPMs. If the TPS is way out of adjustment, I could see that maybe limiting RPM range.

 

I have a box full of random sc4 sensors in the garage back home. When I get home I’ll try a few on and see if I notice a difference in running condition.