Hello everyone. This car is driving me absolutely crazy. I had the P0174 code and check engine light in June 2022. Mechanic changed so many things I can’t keep track anymore. Finally he changed the bank 2 upstream sensor. And the code and light was gone got car inspected in October of 2022. April 2023. Check engine light came back on. Same P0174 code. After a few weeks. Started getting P0171 and P0174. Kept coming back again after more numerous repairs. Been trying to get this fixed since then. Can’t get inspection with check engine light on. Automatic fail. So last week I cleaned the Maf sensor. Light came back on !!!! This time only P0174 again. Cleared the code. Disconnected the battery. Now I’m getting just P0174. Car starts and runs fine. Cleared it again. And will see what comes back next time I drive it. Now here’s a new problem. My passenger side low beam is not working. All other lights on the passenger side work as well as all other lights all over the car. Removed the bulb. Filament was broken. I noticed the bulb turn on then when I try to put it back in the headlights housing. Then shuts off again !!! Buy a new 2 pack of bulbs today. Still not working !!!! Here’s the kick in my ***. Even if I solve the P0174 code. I still will fail inspection now because the headlight is out ! Any help is greatly appreciated

 

NYC, I would first check fuse F17 (assuming you have a 2002-2003 X-TYpe). That is very possibly your problem with the headlight. If that is good, then I am thinking you have a bad wire that runs inside the headlight housing to the back of the bulb. This wire is known for getting hot and the wire cooks itself to the point of failure. If this is the case, then you will need to get a new wire to put in there. If you need help with this, let me know.

As for the P0174 code, as much as I hate to say "throw parts at it", I would try what worked the last time and throw a new O2 sensor into Bank2. At least this one is easy to get to as it is right under the air box. After that, I would be looking at the IMT o-rings and the line going to the brake booster that feeds into the top of the intake. I know people have had a problem wtih that fitting in the intake leaking, leading to a P017X code. After that, I would find a friend that like cigars, have him smoke it and blow the smoke int othe engine bay when the motor is cold. See if you can spot the smoke making a sudden change in direction. That will point you to the location of your leak.

 

Thank you. Solved the headlight problem. My car is a 2006 VDP. Fuses are different numbers for mine. Than earlier models. Just a little info for who may need it. I finally looked up in my owner’s manual. And in fact. Low (dippedbeam) headlights. Are fuse F29 for drivers side. And F30 for passengers side. Pulled one fuse out and the drivers side went out. Put the same fuse in the passenger side. And behold !!! I got a headlight again. Thx for all ur help. I’m gonna also take ur advice about the O2 sensor. Paid $350 bux for a OEM JAGUAR part. . Didn’t even last a few months. Of low mileage driving. I will keep u posted about the P0174 soon. Thx again

 

Stick with a pre-wired Denso O2 sensor and you should be good. Denso is the OEM manufacturer for the factory sensor. Since it was recently done, should be fairly easy to pull too.

 

Thx Thermo. That would be bank 2 upstream Denso O2 sensor. Correct ?

 

NYC, yes, that would be correct. Here is a few that I would say to go with that will not break the bank. Also, a good O2 sensor removal tool is worth its weight in gold.

2002-2008 Jaguar X Type Oxygen Sensor - Autopart Premium APOS0118C - - PartsGeek.com

Air Fuel Ratio Oxygen Sensor Upstream for Jaguar X-Type XK8 XKR #Denso 234-9029 | eBay

The socket:

Equipment Socket Removal Tool Black Replacement Universal Oxygen Sensor | eBay

5Pcs O2 Oxygen Sensor Socket Wrench 3/8" 1/2" 22mm Auto Repair Installer Tool | eBay (use the black oxide pieces from the kit, the chrome socket is worthless unless the sensor is only in finger tight.)

Enjoy.

 

Just went through all this with my 2006 X type, and finally got the light out.

Agree with Thermo, get Denso and Bosch upstream and down stream sensor.

Hopefully Thermo will jump in with the technical terms, but until then will do my best to explain.

In the intake there are two brass fittings one for power brake booster and one for tank evap vent. Test these with your OBDII scanner set up on the short term fuel and spray with MAF sensor cleaner while watching your scanner. I tried all other chemicals including either and nothing changed RPM, but with the MAF cleaner the car died. Usual automotive o rings aren't thick enough to seal the vacuum leak even when three are stacked in there. Go to home depot plumbing and look in the faucet department for their assortment of o ring washers. In their assorted kit, there are a few orings that look like fat little donuts, which seal off the brass leaks perfect. little bit of momma spit and the fittings slide in.

Remove the power brake booster hose and suck on each end to check for a leak. Also check and make sure the one way valve is working and holding vacuum.

Next to the aircleaner, is a black box that slides into the air plenum between the MAF and TPS, put a clamp on it.

Check your PVC and hose for a leak as well with MAF cleaner spray.

My IMT o rings were perfect, which i found odd, but here we are. Most times these are a problem.

Then drive a hundred miles or so and it should clear.

If not buy a smoke machine and smoke. Step up with the oil as most home remedies and the smoke fluid from Halloween leave an oily residue.

Here is what i bought




must have even if you build a smoke machine.


awesome quality but you do need at least a nail gun compressor

Atmospheric pressure is 14.7 give or take, i did crank the compressor up to about 20 lbs right or wrong.

If you check the evap system directly, don't go over a pound or two.

I'm sure i left a bunch of typos but you should be able to get what you need.

good luck!!

 

Ok. So it seems like after the MAF sensor cleaning I’m not getting the P0171. Not pending either on the scanner. So far after each attempt to get rid of both or either codes didn’t do it until the maf sensor cleaning. I don’t know. Im gonna clear the codes again one more time to see if the P0171 is truly and hopefully gone. Ronx thx. lol. I changed out the big 3 vacuum leak usual culprits. Brand new brake booster and line etc. I will try spraying around the area u said. And report back. If this P0171 don’t come back at least we’re on the right track. Might be able to actually get my inspection I hope.

 

Thermo. Is this the correct O2 sensor for my 2006. Lemme know please. Thx.

 

NYC, yes, that is the correct one.

 

Ordered a new bank 2 upstream o2 sensor. Haven’t had a chance to install it yet. But here’s what’s happening. P0171-0174 for months. Changed big 3. New brake booster. New fitting on intake manifold. Same codes keep coming back. Can’t pass inspection since last October!!! So almost a month ago. I cleaned the maf sensor and that seemed to get rid of P0171. Wasn’t even showing as pending. Yesterday checked codes. P0174 current. And P0171 pending again !!! I did a data log with freeze frame on my c-reader scan tool. Here’s what’s showing. Any help please on this. Sick of throwing parts and money at this problem and never gets resolved. Car starts and runs fine. Good gas mileage. I get the 3000 rpm limit when the check engine light comes on. Clear the code and light. And car flys over 3000 rpm with a lot of power to spare. Please help
to decipher this freeze frame data. Gotta get this fixed. Losing my patience. Thx for any help.

 

Got the freeze frame data when my code was set. Anyone able to pin point my problem please