transam02

Lately my car at idle has been surging up to around 1000rpm and back down to around 500-600rpm. It'll continue to do this for a while, but then stops. I'm guessing it is going into limp mode.

Well last night one of my friends hooked up his Diablo Prog. to my car. It was saying that my front 02's were slow to respond. Does this mean that I need new 02's or better extensions?

If I get new 02's i've heard that it is better to get the vette 02's because I won't have to use extensions. Is this correct?

Any help will be greatly appreciated.

Nine Ball

iTrader: (38)

The surging sounds more like you have an air leak behind the MAF. Check your intake bellows, as well as the intake manifold, and possibly for any loose PCV or vacuum hoses. Bad 02s don't really cause surging, they just cause much reduced power.

transam02

I removed all of my air/egr. Is there anything I could have knocked loose.

My car is a 99 and it doesn't seem to have the same air vacuum hose setup that my friend in an 02 Z28 has.

I must be missing a hose somewhere, but where?

Tiger2o69

iTrader: (16)

ttt anyone

jimmyblue

iTrader: (11)

As sensors age (or get crusted up) their response time gets
slower and output signal less. At some point this begins to
affect idle as the mixture control loop (which is what's
bitching about the slow O2s) gets slow enough to interact
with the IAC loop.

Seen this on other vehicles I've had and fresh O2s clean it
right up. About every 50Kmiles or so I have to change them
out on the MkVII. If you have a lot of miles or burn a lot of
oil then you might just want to feed the beast some fresh
meat.

If you have the means to monitor O2 voltage directly and
see the O2 spending a lot of time zeroed (or < 200mV) at
idle, rather than bopping around at a few Hz and tighter to
center, that's the signature of a stale one.