why does my car suddenly want to idle at 1500rpm ish?
i didnt touch the throttle or anything, on stock ecu, it would idle at 800 and now it would idle at 1.5k...

 

It's getting air from somewhere. The only way for MS to add air to the engine is via the fast idle control (BAC or equiv.) valve. If you have one of these, check to see if it's energized when it shouldn't be, or just disconnect it temporarily. If it's not a fast-idle valve issue, then the issue is outside the ecu. Look for vacuum leaks, a sticking throttle plate, or incorrectly adjusted aftermarket TPS.

 

could be that the timing is advanced a little too.

 

vac leaks are checked
i set the VE up to the 80s range for idle and it idle right under 1k, but it is not smooth...

 

so yeah
it owuld either idle great at 1500
or idle shitty at 800 ish

 

Post a log - I'm sure help will be offered.

-Mike

 

is it a stock motor? good running condition before megasquirt was hooked up? i would check for vac leaks, if tps is adjusted right, if the throttle plate adjusted right. if the thermowax isnt stuck. my car still has all the factory cold start items still hooked up, so when i first start it,cold, the thermowax changes my tps voltage higher than normal idle. once it warms up the idle drops to about 1000. i do remeber having to adjust the throttle plate once but i dont remember if turned back to stock. i found that on my car, it wasn't a megasquirt issue that was keeping me from idling correctly but more of adjusting the mechanical part of it to work with megasquirt. for like a week i was chasing the VE table to solve my surging problem when it was actually a bad tach signal wire, which had a bad connection.