As I was driving my car a couple months back my car seemed like it did a little hiccup and my check engine came on. When i got home and read the codes is threw a p0171 and p0174. Running Lean. I was told it most likely was a vacuum leak. I replaced the Crank hose as I heard the stock smooth one was always faulty and The O shaped rings which definitely had a vacuum leak. The second time I checked the codes it threw the same plus 1796 1797 and 1642. Car runs and drives fine. I tried disconnecting the battery and it didnt reset the CEL. Any ideas?

 

Ok UPDATE, so I just went by my mechanic and he ran the codes with the European reader and it threw a bunch of codes. It threw a misfire code, a misfire code for every cylinder, o2 sensor bank 1, o2 sensor bank 2, Lean bank 1, lean bank 2, Can miscommunication, Low voltage, etc. I asked him what he thought and he thinks it came from when I had the vacuum leak on my O-rings. He said that there was no misfire and the car ran great. He reset the CEL and said drive it, if it comes back on bring it back and he will reread it and go from there.. Hopefully it doesnt come back, Im just glad I didnt have to pay Jag $150 to diagnose

 

I think sometimes those who really appreciate (love?) their cars try to do too much too soon when something goes awry. I'm certainly guilty of that "crime". I think letting it sort out for a bit is the correct call, especially if it's running fine after the changes you made.

As an example, my wife's car recently wouldn't start. It would crank, but fall just short of firing up. I was 100% certain it was the battery and it's been so unusually cold here this winter I surmised that the cold had sapped her battery. After a few tests with the multimeter, the battery showed fine. All systems go. Perplexed, I let it sit for an evening and it fired up the next morning. Been running fine ever since (this was about two weeks ago).

Anyway, to make a semi-pointless story come to an end I hope everything works out for you. Cheers.

 

funnyact, based on what you are describing, you most likely have either a battery that is starting to go or your battery cables are starting to develop an internal resistance and this is raising hell with your electrical system. But, like the mechanic said, drive it and see what you get. Sometimes the new systems will get mad and just throw random stuff at you. Something as silly as a little voltage oscillation will take the computer and make it think all sorts of things are wrong.

 

Yeah, I bought the car about 8 months ago. The guy I bought the car from had the battery replaced about 2 weeks before I bought it. I checked the battery and it came back fine. I know the people I bought it from rarely drove it since it only had 78k miles on it being 10 years old. I let it sit here and there too since I bought it just to have a second car that was an automatic and had a backseat. Maybe the battery drained a little from sitting. All in all I know I had a pretty bad vacuum leak that I found after the CEL went on. It was the infamous O-Ring. I replaced both. Im a little surprised that if that was the culprit it didnt take the CEL off of it. I did drive it sparingly but I put about 800 miles on it since the O-ring was fixed.

Hopefully it will all be ok now. Fingers crossed. Like I said, car runs good, smooth. The only thing that I can say sometimes feels a bit off it sometimes it shifts a little hard when you gas it after its slows down and hits the sweet spot while its downshifting, but again. Never had a problem, no limp mode, runs fine.

Thanks for the feedback guys