Codes, codes, codes... now where to start???
 

Hey,

I'm starting the process of getting the Disco 2 that I just drove down from NY, registered in my state. I had a cracked exhaust manifold, which I just replaced and I was hoping that that would take care of my Too Lean Codes. Well, once it was all bolted back together I got a few new ones popping up now and I can't get it past emissions until I get that pesky SES light off the dash board.

So here's what I've got, Anyone experience these kinds of codes together before? Just looking for some pointers before I start replacing everything related to the codes...

P1590 - Idle speed control
P0171 - Too Lean Bank 1
P0174 - Too Lean Bank 2
P0734 - Gear 4 Ratio Incorrect
P1175 - Manufacture Controlled fuel and air
P1172 - Manufacture Controlled fuel and air

Now keep in mind these codes don't all pop up at the same time, They come up 3-4 codes at a time, I clear them to see what keeps coming up, then another 3-4 come up at the same time. The one that keeps coming up is P1590 pretty much no matter what else comes and goes.

So is there an idle control valve or am I looking at replacing the MAF??

Thanks in advance!

I had P0171 & P0174 - bought a used MAF, and they cleared up immediately. Usually when they're together it's the MAF and not your O2's.


So I'd replace the MAF first, then clear and see what comes back.

Just my experience, no more no less...I'm a long way from an expert.:D

Thanks for the input, out of curiosity, what did the MAF run? That would be the most logical choice seeing as how the others are MAF related as well...

You can also clean MAF with cleaner made for the purpose, when it is stone cold. Also see link in my signature for RAVE shop manual, and a separate one on the D2 ECU with all the codes and how they are produced.

The 1590 is for your 3 Amigos, has nothing to do with the engine, and yes, a new Bosch MAF will fix the rest of the codes. Best price I have seen is thru British Parts of Utah, do not try a after market or generic Bosch, they will code as soon as you plug them it. You must buy a replacement with the same part number on the barrel of your old MAF.

P0734 is MAF related as well???

Yes, because the tranny ECU talks to the engine ECU, and believes that power conditions (torque and rpm) are not correct for that gear. So engine is producing less power than the transmission would like to see. 0734 is a tranny ecu code and found in the automatic gearbox section of the workshop manual.

I paid $80 for mine out of an identical '03 DII. I think new they're in the $130-$150 range?

Friend bought one for his daughter and she drove it right through an overheat.......

Whoops. Now, instead of 100's of parts in the engine, there is one.

Too bad, it was one of the light green ones.....always liked that color.

good info, thanks. I've ordered a MAF and will advise if it resolves the issues.