I installed a new MAF to correct the codes 171 & 174, after about 225 miles the code 440 popped up.

Phil

2000 Discovery 85K, great LR

 

Is it 0440? 1440? What?
The only 440 I found is a 1440 and it is a EVAP fault, check and make sure the gas cap is tight.

 

P0440 is a General Evap failure that the computer can't diagnose the exact issue on it's own. Typically a gas cap will give you a large leak code, not the general failure. Make sure you didn't leave a vacuum hose disconnected that attaches to the purge solenoid/intake manifold.

 

It was PO440 and not 1440, I removed the gas cap and reinstalled. This may have been the problem. I filled up before the code showed up, about 40 miles latter. I will drive in the morning and post what happen if anything at all.

 

If the gas cap was the issue the light will turn itself off after a few drive cycles.

 

440 is a evap system failure not a leak as in a gas cap being off or loose.
A mechanic may be in order unless you are very familiar with trouble shooting the evap system.

 

It was the gas cap not being tight. Thank again for the feed back.

Phil

 

I hope you are right, but that 440 code is a malfunction code not a leak code for the evap. If it comes back, you will need to look more into a complete evap malfunction.
Good luck.

 

I just got this code, have cleared it with scanner, filled tank drove it came back, check gas cap it was tight, have cleared it three times, where should I start looking for the problem ?

thanks

Doug