Re: Quad 4 Closed Loop Question

Any codes showing up? As was mentioned check the coolant sensor. It can be 
monitored on the OBDII tester.

"Scott Buchanan" <t120rv@[EMAIL PROTECTED]
> wrote in message 
news:BeCdnZh4R99r9JDVnZ2dnUVZ_gydnZ2d@[EMAIL PROTECTED]
> My car generally runs good. A problem is that sometimes, about a minute
> after a cold start, it will stumble for a few seconds. Usually I'll be
in 
> a
> parking lot or in the driveway so it is not much of an issue. Last week
it
> happened after I pulled into traffic.
>
> A scan tool shows that it goes into closed loop about a minute after a 
> cold
> start (40 deg F.). It cycles back to open loop then closed several times
> before it stays closed. This happened before the O2 sensor reached .5 
> volts.
> I think that this might be a clue to the problem. Once running hot, the
O2
> sensor will cycle from rich to lean several times a second.
>
> My question is what allows the engine to go into closed loop?
>
> Thanks
>
>