So I thought everything was fine and dandy after my headgasket job turns but as I was sitting at a red light today the idle felt rough for a second and then the check engine light went on. I checked the code screen under the passenger seat when I parked the car and it was displaying code 45. I read on other forums that this is an Oxygen sensor code but probably not directly related to the oxygen sensor itself. Truck is not overheating... Any ideas?

 

Mine just threw that 45 code on my 95 other day and 2 times previously with a rough idle too. Runs fine at speed. But mine is due for a tuneup so.........

 

Hmmm... Not too sure what exactly is going on, going to do a bit more research though. Talk to some mechanics. At least i'm not getting misfires whew. The rough idle made me thing it was a misfire in the beginning, will put the B&G44K in once my tank is quarter full and see if that clears anything up...

 

Mine did the same thing a couple of years back towing a HEAVY trailer, right at a stop light too, rough idle then kinda fixed itself on the rest the drive home (several miles). Drove like this for a couple of months, MPG dropped to about 10MPG. Finally replaced O2 sensor, all good. Moral of the story, trust what your Rover is telling you. Code 45 is right bank (passenger side O2 sensor). If you want to confirm before buying an O2 sensor you could swap drivers & passenger side sensors and see if you get a code 44 for drivers side when the suspect O2 is moved.

You could also reset your OBD I computer (disconnect battery) and see if the code comes back. If it does it's your O2 sensor, especially if there's a possiblity that its the original one with all those miles. Mine failed ~140K. I have the same 5spd Disco as you, except mines 95.

 

O2's..........Ok so who's got the best smokin deals on these. As I suspect that may be my problem too. I have the CEL kick on a once a week with code 45. I just reset the light and it runs good for a while.....weird huh? LOL

 

Not sure, maybe British Atlantic for brand new OEM? I'm sure others on here will chime in. I never bought new ones, I have a wrecked parts Disco with very low miles and was religiously maintained at the local LR dealer. I got my "new" O2 senor off it. I guess one day I'll shell out for some brand spankers when the drivers side fails too maybe LOL. I'll ssee what others say is the best place to get them.

Your code resets for a while probably because it takes a while for the sensor to trigger a failure as it's going out.

 

Yeah, it does....... I found new OE O2's from Rovahfarm for $113. But I am doing a tuneup first, as it needs one. And maybe that will help with the rough idle, etc..

 

Gentlemen hold up on the $200 repair job for a moment. 44 and 45 are merely telling you that the (left bank or right bank respectively) O2's are sensing improper (out of range) levels. This could be from something as simple as a loose spark plug wire causing a misfire or a dirty MAF. Check all your connections first, make sure the rotor and cap are good. I assume the plugs, cap and rotor are all new since you just did the head gaskets?


And the BEST deals on the correct O2's (NTK 25016) at the moment are PTSchram, BP of Utah, Roverguy.com and AB... All at $100 is each and that is WITH the correct, round, three pin plug already attached... no splicing needed.

Having said all that at your mileage Losinov and IF those are original sensors they aren't doing squat anymore. Replace em anyway unless they are under 80k miles.

 

Yeah new plugs, wires, cap and rotor. My MAF did have that metal screen in it but it shriveled up when it came in contact with some brake parts cleaner, a light mist of it actually. i was worried that screen had something to do with sensing other than just a block for foreign debris. I poured a bottle of B&G 44k in today, going to drive till the tank is out maybe it will help with the idle. Still seems rough though. No idea if the o2 sensors are original though, no previous maintenance records. Thanks for all your thoughts guys, but still unclear on where I should start checking?

Should I pull the plugs and make sure they are all in good shape? Check the injectors?
I will try swapping plugs and seeing if I get a code 44, reset the computer and drive like that for a bit to see if it triggers it again if not I'll put the original o2 back on the passenger side and see what happens, then I'll think about replacing them.

 

Funny. I just did my head gaskets and had a similar fault if not the exact same fault. Cleared the faults per Cosmo, have not seen the fault since. I do still have a bit of a stumble every now and then at idle when taking off. I suspect a spark plug wire as I caught one grounding on the engine puller bracket by the power steering pump.

Is there a performance plug wire that is heavily insulated to stop this from happening?