Greetings! I am getting a Code 44 when I am stopped at a light for more than a minute. It only occurs during an idle after the engine has warmed up and is running in closed loop. The MAF was causing the engine to surge and run really rough so I was hoping that replacing that would fix the code 44. The new MAF fixed the poor running, but I still get a code 44 at idle. The RPM's creep way down for a few seconds and then revs back up to smooth and throws the code. After this, the engine runs with less power until I shut it off and the code disappears until next time. I have hooked up a fuel pressure gauge and although it fluctuates by 5 psi when I'm really driving hard, it stays constant during idle even though the RPM's start to bog. Any ideas?

code 44 for a 2.8L V6 is a bad o2 sensor, to confirm this is bad i would start the car and let it warm up and when it reaches normal operating temperature, walk around back and smell the exhaust, if it smells like rotten eggs or has a sulfur smell your o2 sensor is def. bad. Other than that, the rough idle at a red light sounds like your egr valve might be stuck open, you should have no egr at idle, and if you do it can really mess things up, if you can take it off and spray some carb cleaner into it and if that doesnt help it might be time for a new one. Goodluck!

That'll be something to try. This car has sat up for 4 years and I have been replacing things left & right since it has been back on the road. I don't mind because they have been $100-a-pop type items. It has NEVER had the EGR replaced, so I will try that. The O2 sensor was replaced right before it was stored but for only $30, I can try it as well. I'll do them one at a time and post the results.

Yeah ik where your coming from. my car sat for 3 years and i was doing the same thing, replacing parts left and right, but ive had 2 egr valves on since i got it, and i had to replace the o2 sensor, they just go bad out of nowhere sometimes....but yeah let me know how it goes, the o2 sensor can be a bitch tho, my was rusted into my exhaust and we almost couldnt get it out, its a downstream sensor and i think its right after the y-pipe.

RandogLeader,

Did you manage to fix your problem? If so what was the fix?

After replacing the missing thermostat in my 90 350TPI, I am getting exactly the same symptoms as you.

Any help greatly appreciated.

Rockstar!

did you reset the computer after installing the new maf?

Yeah, computer has been reset. Funny thing is that she drives like a scalded dog when I first take off in the morning. After she warms up really well, the performance goes down and she drives very "sluggish". The code 44 comes and goes, and the worst is when you drive for about 30 minutes or more and then shut it off (to go into the store or something) when you fire it back up and take off, it is VERY hesitant even though the SES light isn't even on. There is some issue involving heat because it will run awesome again after it has cooled off completly. I'm suspecting the EGR valve to be involved but haven't had enough bread to get one as of yet. There's a bad front tire that keeps growling at me to be replaced first. Any ideas?

I was having this problem recently and I had an exhaust leak giving me the code 44 " lean exhaust " . If you have an exhaust leak befor the sensor that could be your problem .

How did you know that you had a leak? Was there exhaust gas showing around the manifold joints because I don't see any smoke when I rev the engine and look around the manifolds/y-pipe.

Disconnect your O2 sensor, and see how she feels after being warmed up....

My passenger side flange was leaking because of a broken stud so I made up a rig to tighten it without using tie wire or a coat hanger until I can pull the manifold off and replace the stud .