Not going into closed loop, HELP!

[fly89gta]

Ok, here's the deal, i just recently put blue tops in with a thrasher 92 chip for them

If i'm part throttle under 2K RPM's i'll be in closed loop(the O2's bounce around like they should) but anything over that they O2's stay around 850+!

I really need help guys, i didn't have this problem with the stock injectors and Thrasher chip

I'm getting around 10 MPG with only 42#'s of FP line off, i have an AFPR on its way, also i'm only getting like 13#'s of boost, i have to figure that out now too

but it seems i'm entering open loop when over 2K RPM's..i can't have this, 10 MPG is unacceptable

TPS is a smooth increase, .42-.44 at idle, IAC seems ok...i hit open loop at idle which i'm suppose to. O2 has like 4K miles on it, i'm about to just get a heated one...anyone have ANY ideas?????

thanks guys!

 

[azgn]

sounds like you have a vacuum/exhaust leak somewhere and you need to try a new 02 (get an AC, not Bosch) I would swap the chip also

 

[fly89gta]

Originally posted by azgn
sounds like you have a vacuum/exhaust leak somewhere and you need to try a new 02 (get an AC, not Bosch) I would swap the chip also

i checked for vac. leaks, none...next is the exhaust leaks...O2 is on its way...u think i should change chips eh? hmmm any suggestions?

 

[DCVING 6]

I have heard the terms closed loop and open loop alot. What is the difference between the two? How can you tell when you are open or closed?

 

[azgn]

have you actually checked your vacuum(with a gauge)? exhaust leaks can be hard to find......just get another Thrasher or find somebody nearby with a chip that matches your setup

 

[fly89gta]

Originally posted by azgn
have you actually checked your vacuum(with a gauge)? exhaust leaks can be hard to find......just get another Thrasher or find somebody nearby with a chip that matches your setup

yeah i have my vac/boost gauge, at idle in park i'm at 20'' of vac, 15'' in drive @ idle

 

[ThikStik]

Open loop at idle is normal? The coolant temp sensor is the only
sensor I that I 've heard of that signals a warmed up motor so ecm can go into closed loop.
good luck

 

[fly89gta]

Originally posted by rick cain
Open loop at idle is normal?

I have a thrasher chip, they go into open loop at idle

 

[fly89gta]

BTT, is that amount of vacumn normal? too high, too low?

 

[bruce]

Originally posted by rick cain
The coolant temp sensor is the only sensor I that I 've heard of that signals a warmed up motor so ecm can go into closed loop.
good luck

Nope,
Yes, there is a min operating temp for closed loop.
The engine also has to have been running a given amount of time. There must not be any sensor failures causing a default value to be use.
The O2 sensor must be generating a min and given min high voltage.