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Hello guys. Just took a long drive and check engine light came on. Checked the codes and got these : P0171 lean bank 1. P0174 lean bank 2. P0430 catalyst efficiency below threshold bank 2. Any help is greatly appreciated. Thx.
NYC, because you are getting codes on both banks, odds are , you are looking at a bad PCV hose (ie, it is leaking) or the brake booster line that is tied into the top of the intake is leaking. Normally, if your IMT valve o-ring is going to leak, it will cause a leak on one side or the other, but not both. I would also look at the accordian boot on the front of the throttlebody for signs of a hole. That would also cause what you are seeing. As the plastic gets older, it is going to crack easier. I would also recommend doing a cleaning of the MAF sensor. Could be something that simple.
I think you fix the P0171/0174 codes, the P0430 code will go away on its own.
Thx Thermo. I was chasing a P0174 code a few months back for a while. My mechanic changed out lower intake manifolds and many other parts. Seems like changing the bank 2 upstream I think sensor bought from Jaguar oem one fixed that code. Everything was fine for the last 7 months. Now this. Any more help or info would be great
NYC, right now, I would say buy a nice cigar, start up the car when it is cold and enjoy the cigar, blowing smoke into the engine bay to chase any air leaks. You could also try using a piece of tubing and putting one end near your ear (DO NOT!!!! form a seal) and run the other end all over the engine. When you get near the place that you are sucking in air, you will hear the sucking sound. Start with the obvious and go further and further into the depths.
Thx again Thermo. I cleared the 3 codes about a week ago. Drove the car. Check engine light came back on. Now I only have the P0174 code !? Weird. I was trying to get rid of this same code months ago. And finally changed out the upstream o2 sensor (if I remember correctly) lol , and the check engine light didn’t come back on for months. I bought an oem jaguar o2 sensor for $325 bux !!!! Could the sensor have failed in just a few months ??? Please help. I don’t wanna see this code anymore. Car seems to be running fine also
NYC, if you are only getting the one code, then I would a quick ether spray check of the IMT valves. From there, you may want to check the tightness of the intake as you might have a bolt or two that are not quite tight.
When was the last time you cleaned your MAF sensor and/or throttle body? Those could be compounding the problem.
I’m pretty sure my mechanics cleaned those parts when we were getting this same code in October. I also cleared the code again and check engine light came on again. Same P0174 only code again.
Getting the P0174 code again. Car seems to run fine. Intermittently also getting P0171. Any help is appreciated. I have a code reader that’s not so great. But here’s some pictures of what I’m able to see. Again any help is greatly appreciated.
May be worth swapping the two upstream sensors over from bank to bank . If that makes the code switch to a fault on the other bank you may have a sensor gone again.
Help with codes please
