[julio]

Hello all!!! i have a 1999 discovery series II with 130k and my check engine light just turn on last week. So i took it to an auto parts store and they told me that the results were codes P0741 Torque performance ckt performance or stuck off, P0705 Trans range sensor circuit malfunction (PRNDL Input), P0171 System too lean (Bank one) and System too lean (Bank 2). My question is where do i have to start to check all this codes and where are all this things are located. thanks in advance for ani advice.

JulioPuig

 

[Disco Mike]

What sort of maintance have you done on this truck?
Have you replaced your O2 sensors yet, how about the plug wires?? This along with a good tune up will help with the lean run problem.
As for the transmission codes, can't help you there.
Mike J.

 

[Rovin4life]

I would suggest a MAF, but usually the trans codes that follow is 0703 and 0704. Its a fourth gear monitoring and third gear monitoring codes

You could have a problem. I would have it diagnosed first. Lean codes can be caused by a number of things. The list is as long as engine parts. The Transmission codes are set because the PCM sees the lean codes and changes the shift points and the like for the condition.

Check for every vacuum leak first. That causes a lean code. too much air.

but after that you need Testbook to really look at whats going on and whats in the freeze frame data.

 

[julio]

well i just got the truck like two months ago and i havent made any tune ups at all!

What will i have to change besides spark plugs ,wires and air filter.

thank you.

 

[Rovin4life]

Changing that stuff will not cure your check engine lite.

You need diagnosis.

Especially with those tranny codes.

Its possible the person new they needed a new tranny and had it reset and sold to you.

 

[julio]

But the tranny works fine!

 

[julio]

when you reset the codes does it takes that many time to come back?

 

[julio]

its been two months already!

 

[Rovin4life]

not likely,

get it diaged. Those tranny codes arent good.