Chugging - open/closed loop problem

[tokashikibob]

Gents,
87 GN daily driver that has been running poorly for a year. Car chugs/rich a runs like a POS barely able to run light to light. However, when the computer switches to closed loop car runs great. I can see the switch due to air/fuel meter on the dash. When that is flashing the car runs normal, when it is dark which I expect to be open loop the car is in bad shape. It is unpredictable when you get in / drive what loop it may/is in. I could start it up and air meter lights up and runs great, then maybe later goes in open loop and runs poorly. Sometimes just the opposite.
It runs in the open loop (Great) more often when the weather is hot. Shitty in the winter. Water temp usually is 190, but does not seem to affect the loop switch as it could be cold or hot running great or poorly.

Replaced:
EGR valve
Fuel Pump and Filter
Coil Pack
Coil control Module
Plugs
O2 sensor
Maf Sensor
TPS
It has adjustable Fuel pressure reg, so I checked that, looked for vacuum leaks, checked voltage at MAP. Replaced and readjusted the TPS for proper voltage.
I'm wondering if it is a computer problem. Is there any other checks I should look at? Anything with the computer? Can I just get a regular 3.8 computer and put in my chips?
Thank you in advance for any suggestions.
Bob

 

[xrunner123]

What injectors? Chips must me burned for the correct injectors.

 

[SHADOWII]

Are you sure your maf is the correct one for our cars or are you using an upgraded model like the lt-1 or ls model w/translator? Also, check for leaks around your cai pipe/tube. Unmetered air can wreak havic, you experience that when your up pipe blows off the throttle body. When cleaning your maf you have to use an appropriate cleaner, oils or some general purpose cleaners can destroy the sensor.
What does your plugs say, discolored, raw fuel, no fuel, etc. Hope this helps.

 

[Chuck Leeper]

"
Water temp usually is 190, but does not seem to affect the loop switch as it could be cold or hot running great or poorly."

if it's going into closed loop, and the engine is cold, I'd be looking at the temp sensor, and the wiring.

 

[earlbrown]

any chance that MAF sensor is a stock replacement from a fast food parts store?

 

[tokashikibob]

Thank's for all the tips! I'm going to replace the water temp sensor ASAP and see how that goes, I'll report back soon. No fun driving a 10 cyl FORD E350 as a commuter :^(

Bob
www.okinawarelics.com