I have a 90 civic si with ls vtec and its wired for obd1. Everything is great besides it not going over 3700 Rpms. I have the vtec selinoid, and vtec pressure. So there are some extra wires. Does anyone have any idea what might cause the rpms to not go any further than 3700?

 

Do you have the knock sensor? Everything has to be wired up... Also you really NEED a tune to be running LS-V... If you had one you can eliminate someof that stuff out as well.

 

Yea its tuned

 

any codes in the ECU? - usually when in won't rev up, it is caused by a bad distributor (or not wired correctly) and you will have a check engine light with a code 4

 

No check engine lights. Maybe cause its tuned?

 

Sounds like your in limp mode. For the carto do this there must be a CEL.

 

Ok so I switched to a stock p28 ecu. It worked fine for a min. Then started again. So I unplugged it, worked fine, then went bad again. Not throwing a code.

 

recheck the wiring. that is most likely where its messed up