When it rains or pours. I'm battling some leaks and updated a couple of things. My MAF is about a day old (last one went bad). I replaced the rear O2s too. One was throwing a code.

I was getting some random codes right before I replaced the MAF, including the 01173. All went away except that one, then I got two new ones. I checked the connections on all O2s (and they seem to be giving normal and fluctuating values), checked purge valve connection and every other connection in the engine compartment. There are no pending codes. I'm using premium gas.

I did have a glorious few hours without the SES light.

Has anyone had the combination of P0171 P0174 P01173? I cleared them and they came back so I guess my Rover is serious about them. I checked the forum and I don't see anyone with just those codes (who has a new MAF and recent O2s). Engine seems to run fine. No smoke of any color our of the tailpipe.

When I replaced the rear O2s they were blackened on the upstream side, but I attributed that to rich running because the MAF quit (it was not showing any air volume on my scanner).

Thanks for your help,

Charlie V

 

my money is on vacuum leak

 

The bane of my existence. I had one before and it was the upper intake gasket. I'd put a little crease in it. Maybe the bolts are loose....? I'll check everything over but my history of pinpointing vacuum leaks leaves alot to be desired.

Dusty, you, Disco Mike, Jafir, ARMY Rover, Coors, Jared, and many others make keeping my Discovery, which I have had for fifteen years and drive and enjoy every day, possible. I appreciate your dedication to this forum and to the fancy, aging, British Jeep that is my hobby and main transportation.

 

I had scan codes PO130, PO171 and P1171 after completing the HG/Intake Manifold work and when everyone else said start replacing O2 sensors, Dusty recommended starting with the big vacuum line, going to the brake booster. I had the luxury of using a higher-end code reader that gave me 'real time' data from the O2 sensors, so I could actually SEE the output of the sensors, which were performing within the expected range.

It ended up being the rubber vacuum connection just BELOW the line from the plenum to brake booster. These tend to swell with age, making for a sloppy fit. The cheap 'fix' is to tie wrap them to the nipple.

 

Got a new ARB bumper in about an hour ago... At 47 years old I didn't know I could get this excited without having a heart attack. As soon as I get that on I'm going to look for the vacuum leak... probably tomorrow.

 

Sounds like a script for a Viagra or Cialis commercial, Charlie...

 

I know how that goes. fun stuff is always first.

 

Use a stick of incense or a cheap cigar to generate smoke and use this to find your vacuum leak.

 

I tried that once before and didn't have any luck, but I will try again. Basically I remove the fan then hold my smoke maker everywhere I suspect. My success at that is seriously lacking, but insanity demands that I try again, and again.

 

I have the 1173 code. I've had it for along time. It went away for a bit and all the research I did lead me to air leaks in the exhaust. I have tiny hole in my pre-cat exhaust and the code still pops up once in a while. It has no effect on milage or drivability just that damn CEL. I just delete it with my scan gauge whenever it pops up. no more vehicle inspections in my neck of the woods anymore starting jan1/2015...yeeehaaa!