For some reason my lsvtec (P72 head, B18A1 block, PR3 ecu) idles rough and will not go above 4K when driving. I can rev it to hit 7500. this problem is driving me nuts please help! will a knock sensor cause this problem???

 

yes,if you have no knock sensor hooked up it will run like ****,and i know theres no place to put 1 in the ls block,so you can have the ecu chipped to see no knock sensor,tap the block for it,or ground out the knock sensor ...

 

has anyone ever had this problem

 

Is the ecu displaying any codes?

If it is the knocksensor then you can fix that by tapping the back off the block like mr. speaker said.

Check your timing. Has the head been milled more than 10 mils? if so then we you set cams they could be way off.

 

it is throwing 6 (coolant temp) and 23(knock sensor). i am 100% the timing is on. the motor just has no power once it hits 4000

 

wow, read...you need to fix the knock sensor problem.

second. if you do fix the knock sensor problem and it doesnt go over 4 still. check timing. if timing is on..check the cams, they could be flat spotted

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by rsxcrx &raquo;</TD></TR><TR><TD CLASS="quote">it is throwing 6 (coolant temp) and 23(knock sensor). i am 100% the timing is on. the motor just has no power once it hits 4000</TD></TR></TABLE>

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Mr.speaker &raquo;</TD></TR><TR><TD CLASS="quote">yes,if you have no knock sensor hooked up it will run like ****,and i know theres no place to put 1 in the ls block,so you can have the ecu chipped to see no knock sensor,tap the block for it,or ground out the knock sensor ...</TD></TR></TABLE>

you're really answering your own questions...get rid of the knock sensor code and coolant temp code and it should be fine,,if not its timing like these guys are saying.