I have a 2001 discovery 4.0 that I bought for my son.It has a 3 month power train warranty. We had it one month and noticed it was loosing some water(no drips or leaks that I could see) and running a little hot and hoses were under pressure after driving it.We took it in for service and they replaced radiator,water pump,and thermostat. They said it was a flow problem and they supposedly checked the head gaskets with the chemical block test and said they were good.....it still seems to be using water and now I got 3 codes po174,po171 (left and right bank to lean and po734(4th gear ratio incorrect.After reading lots of posts on hear we cleaned MAF sensor and changed spark plugs but the light came back on.
Any one have any experience with these problems????
Thanks

 

Well, if cleaning the maf didn't help, I'd say replace it.

 

Is a bad MAF sensor known for giving those codes???

 

Replace thermostat immediately.
Do not drive it - until this is done.

Listen for the water fall sound at acceleration

 

Yep. Especially the gear ratio code.

 

"Listen for the water fall sound at acceleration"
is this sound good or bad????
I haven't heard it yet

 

It's not a good sound. It means you have air in the system from some culprit(could be a leak, head gaskets, or it hasn't been properly bled). The sound is air circulating through the heater core.

 

ok thanks for all the input.....Where do you guys get your Discovery parts cause Ill be needing a MAF sensor and a thermostat !!!!!

 

Amazon for the thermostat motorad 439-180 and only buy a Bosch MAF or you will have problems.

 

in your first thread you say you replaced the thermostat. radiator and water pump, why would you be replacing the thermostat again? just throwing good money after bad, try preasure test the system before you continue to replace items.