Hey guys, got a quick question about my tbi.

ever since i put this hypertech chip in, i've had a slightly high idle (1500-2000), and I was wondering if i could get it to drop a bit by lowering the fuel pressure.

Another quick fact, i know i'm running rich on top end, right at about 11.5:1 at 4500RPM, would lowering the pressure also help that problem?

 

have you let the car go into close loop? im unfarmilyer with hypertech, but it could be that the chips cold engnie speed is set (1500-2000) never a good idea to buy aftermakert....

agin probly the chip....

 

Best way to change it is to put the stock chip back in. I have one that came with an 8746 ecm I got and its pretty much like the stock chip.

Lowering the fuel pressure will cause the engine to go lean in open loop, and idle erraticly.

 

it idles high in closed and open loop, always. i'll try the stock chip out and see if it makes a difference.

FYI, the car has headers, 3 in exhaust running through a flowmaster, tb spacer and openelement, and an msd coil, will the stock chip still work alright?

 

IMO, the stock chip should work as well as the hypertech one did. As far as I can tell, they really only add some extra timing and fuel in at the upper areas of the spark and fuel tables and lower the temp to enter closed loop.

FWIW, 1500-2000 RPM is a very high idle, should be around 650 in gear

 

11.5:1 is normal. That helps sap all the oxygen out of the exhaust and prevent the cat from melting down during WOT.

 

no cat to melt down, i thought it was supposed to be like 14 to 1 or somthing.