02 sensor problem?

[SleepinGVR4]

My car just started doing this the other day.

My car has to crank a bunch of times to fire. 02 won't oscillate at idle, seems to be stuck around 90 volts. Wideband is reading rich at idle. Idle is higher than where it is set. Car backfires a lot on decel. When I let of the throttle the wideband reads rich for a couple of seconds after I let off the throttle instead of reading lean as soon as a let off. And my fuel pressure bleeds off a instantly when normally it will hold pressure for a while.

But the car seems to accelerate fine and cruse fine.

I swapped in another used 02 sensor to see if it changed anything but it didn't. But that 02 could of just as easily been bad too.

Should DSMLink throw a code if the 02 is bad?

 

[Jesh]

I'm guessing your o2 sensor is fine and your actually running rich. (not caused by the o2 sensor) For instants, if your coolant temp sensor is bad it would make the computer think its still cold and it will continue dumping more fuel into the engine trying to warm it up. Since you have ecmlink it will be easy to check to see if it is working properly. I would suspect the coolant sensor but it could be something else.

 

[Jesh]

Also do you have different fuel injectors? If so what size/brand and what is your global fuel and deadtime set at?

 

[SleepinGVR4]

I'll check the coolant temp sensor when I go back down to the garage.

My injectors are FIC 850s. Global fuel is set at -46.5% and deadtime is set at 360.

My car was running fine before a couple of days ago.

 

[GSX_TC]

im interested to know what it is, let us know how it turns out.

 

[SleepinGVR4]

The coolant temp sensor is working fine.

 

[beaner]

Post a log.

 

[toybreaker]

How's your fuel pressure?

A bad fpr can give these types of symptoms.

 

[grocery_getter]

A bad fpr that pumps fuel out into the intake manifold thru a ruptured diaphragm. Will show a rich sign and bled fuel pressure really quick once the car is off.

 

[SleepinGVR4]

OK I'll post a log here in a minute.

I have an old school SX regulator that I just replaced the diaphragm on about a year ago.

Fuel pressure seems fine while idling. Its where is supposed to be. When I pull the vacuum line off the regulator the car does stumble for a second.

 

[SleepinGVR4]

Nevermind, pulled the vacuum line off again and fuel poured out of the FPR vacuum barb and the vacuum line. /ubbthreads/images/graemlins/banghead.gif

Like I said before, I replaced the diaphragm about a year ago. So maybe time to switch to an aeromotive.

 

[SleepinGVR4]

So I tried to find the hole in the diaphragm but couldn't find anything. Put it back together and seemed to run fine for a minute then the 02 locked again. I disconnected the vacuum line from the regulator and gas started pouring out of the vacuum barb. I checked the 02 while it was disconnected and it was oscillating perfectly, actually better than it ever has. I think the regulator has been bad for a while and now has gotten to the point of not being fixed.

I always wondered why my 02 oscillation never looked quite right. It was always kinda choppy at the high voltage point of the oscillation.

So who's got a regulator they want to sell?