I did a search, nothing new on this since 2006. My car likes to hang the rpms particularly in the 1-2 or 2-3 shift. When this happens, the SES light flashes. I originally was told the SES was for knock detection... (makes sense) but after careful testing and reduction in boost to below stock, it still happens, but ONLY DURING THE SHIFT.

The previous post about hanging revs talked about the computer telling the IACV to hang the revs for emission reasons. Any reason for this to cause the SES to flash? I just got my evoscan and TACTRIX cables in the mail, waiting for a couple of parts before a full tune is done - but how can i get rid of the annoying hang?

Bren

 

Well what is happening to me ( Maybe the say as you) when I shift, the rpm suppose to go down but if stays up even when I'm braking.. I probable have a bad butterfly.

 

mine doesnt last as long as yours does... im pretty sure its ecu/tune related. just wondering what part of the program i need to make changes to to get rid of it....

 

First, i doubt the hanging RPMs, from the emission stuff, wold cause knock. If you'd like to get rid of the hanging rpms, PM and ill help you.

Also, if your gettin knock during shifts, even after lowering boost, check and make sure you downpipe isnt hitting your oil pan, TC or cross bars. The DP hitting stuff would cause shift knock.

 

If you have an intake pipe that is a possible cause.

Your CEL (common name for SES over here) is probably a knock light if you have tephra mods. Reduce your timing in the 100-actual load cells and it should go away (and not knock any longer). There are quite a few posts on this now.

 

I noticed when i installed my new Diverter valve, i the engine speed will go up about 200 rpm when i clutch in and release the throttle. I blame the DV fluttering. I could reduce spring pressure, but then it will probably not hold 25psi. If you have a non-stock diverter valve, check the spring pressure.