i pulled into work today and parked. as i went to shut off lights and the engine the engine light came on. it was only a 10 mile ride, but it was about 4 degrees f. i park in a non heated but insulated and dry-walled garage, and let the car run about 5 mins before the drive. after work i got the code read and it says P0174 system to lean bank 2. i had the code cleared and have drove about 15 mi without it coming back on.

car is a 2004 x-type 3.0 AT, with 80,200mi. has a k+N air filter and i just did oil change with filter about 120mi ago. fuel filter is about 6 mo old

any ideas what could have caused this?

what does "Bank 2" mean ???

thanks in advance.....stevis05

 

read my thread (my x-type projects and installs) that will clear up your problem...most of the time its a vacuum leak ...my thread is long but youll find it with pics...this is a common problem ....

 

I had the same error code when it was colder than usual (35f in so-cal). I undid the battery to reset the code as i could not find any leaks. No code after about 400 miles of driving. Hopefully it doesnt come back

 

IMT orings especially with colder weather. They shrink like, well you know. replace them with the "green" ones from the dealer. They have a sealant on them and sized differently. You can easily take out the 2 8mm bolts in the upper/lower IMTs, pull it out and if its yellow replace them. disconnecting battery does not clear a code, its still there if scanned. I would also recommend replacing the brake booster vacuum line and the smooth PCV hose with the new style ribbed one also

 

I have the same issue. I think mine is a combination of bad pcv line and maybe imt's

 

I had a similar issue.. (Bank 1 lean). I had noticed a hissing sound eminating from the upper IMT a couple of weeks ago. Then the MIL light came on with the appropriate code. Make sure you replace at least the two IMTs and the PCV hose. I did the PCV and the upper IMT (got rid of the vacuum leak there) but the MIL light did not go off....until I replaced the other one..which was also apparently leaking although there were no outward signs (I sprayed the starting fluid around that one with no effect. It is as Brutal indicates smart to just do them all at once.

My brake booster line was still ok, so I didn't need to change that at this time.

 

You could have starved it for oxygen. Less oxygen means too lean. If it was parked in a garage that was sealed with the grill toward the inside of the garage as it ran you depleted the oxygen concentration in the garage. you got a fake reading. reset and read in a 100 miles or so. Again JMHO

 

uh, sorry but if the WHOLE environment has low 02 content, you wont set a code. The car reads the total amount of 02 in the air as a function of 02 sensors, mass air flow and adjust accordingly. It wouldnt read lean if the air around has less 02 just as it wouldnt do it in higher(thinner/less 02) elevations

 

since original post, i have triple checked everything mentioned and then some. after clearing original light, i drove about 50 mi untill it came back on. i replaced both the IMT valve o-rings with the green ones(they have been sitting on the bench for months!!), and removed the breather hose to clean. i then went to autozone to clear the light and instead the guy told me that i have since thrown another code, p0171 system to lean bank 1. they didnt clear the light for me so i went home, removed the two screws holding my MAF in place and looked close at it. it had a dirty film over the glass bulb so i carb/choke sprayed it and wiped very carefully with soft cloth. once cleaned i then saw it has a red tint to the glass bulb, but when i took it out it was black with dust. started car ans still had engine light. dissapointed i said f--- it! and drove about 20 mi to the mall for last minute shopping(like always). when i left the mall and started the car there was no light...x-mas had come early this year!!! drove back home, no light, no limp home mode, and best of all revvs past 3k!!! oddly enough before i cleaned the MAF i ordered 6 ngk irridium spark plugs, 6 intake manifold o-rings(upper), throttle body o-ring, breather hose, and a cabin filter. have drove about 100 mi since light went off with out coming back on. thanks for input and help -stevis05

 

So merely cleaning the maf fixed your light and shifting issues??

 

it seems as though this is true. i changed the imt seals and then found out i had the other code. not sure if i threw it before or after the imt orings, but i cleaned the MAF whick looks like a light bulb of sorts, with a reddish tint. what i found on it was what looked to me like when you grease a ball joint, and a little grease gets left on the fitting. when you dont wipe it off and it collects dirt/dust/particles. thats what my maf looked like. i think that over time, it has been coated with moisture, collected dust, possibly air filter oils,(i do have a k+n re-usable, which requires cleaning and re-oiling.) i think that by cleaning it and running it, the level of oxygen read was far greater than what it was reading when it was dirty, hence shutting the light off once the readings were reading correctly. it sounds crazy to me too, i would think that after repairing something you would need to get the light cleared, and if it came back on then the problem wasnt fixed. im not an expert on these lights and the ecu system and how it operates but it did go off, but not right away.

on a side note, autozone stocks the MAF for the 04 x-type 3.0, as it is a ford part.may fit other years not sure, check it out. the cost was about 83.99 or so but luckily i did not have to purchase. i figured i would clean it once i saw what it was supposed to look like and if it didnt work i would search around for best deal. there is also an oring seal around the base of the MAF , which i am going to replace once i take a dimension reading. looks like itll cost about a buck or two, just to be on the safe side.


-stevis05

 

I have some carb and intake cleaner. Think I'm gonna give this a try when I get home. U have to unbolt the intake tract to access it do u not?

 

the way i did it was i popped the top off the battery cover to make more room. there will be two phillips screws holding the MAF in place into the top part of the air filter cover. once you take out the two screws slide the whole assembly straight out over the battery. i didnt unplug it but i had the car off. WATCH OUT, behind where the screw sits there is exposed metal on the MAF, and the battery + terminal is right there. dont arc them, sparks will fly!! youll see the bulb, it has plastic that extends around it to keep from breaking it. i used a real soft cloth, a q-tip may work. i actually sprayed the cleaner on the rag and then wiped. i also wiped the base where the o-ring is. give it a try might work for you too. worst case scenario you will have a clean MAF sensor, right? -stevis05

 

Sorry to ask but what is IMT?

 

intake manifold tuner. it closes part of the intake at lower rpm to maintain air velocity and cylinder filling, then the ecu opens and and the cylinder has a larger intake runner to draw from. Its all about giving the engine a wider torque curve throughout the rpm range over a fixed 1 size intake manifold

 

thanks for the definition

04 jag x type 2.5

Have exactly the same issue on 04 jag x type 2.5. So far have replaced fuel filter, air filter k&n, plugs ngk. Codes cleared, same issue. Seems to appear when air temp is cold and eng is warm.
Cleaned MAF and while eng was cold missed on acceleration at 2000 rpm.
On returning home had a mis while idling.
Am replacing upstream O2 sensors.
Have read that fuel w/ethanol can cause misfire/check eng/codes
Also fuel injectors? Will adding fuel injector cleaner help?

 

Cleaned MAF sensor and codes and after running for awhile all is good.
Have not installed O2 sensors yet but thats next. Waiting to see if it throws another code first.

 

I dont know why everyone wants to think past what a problem is and advise given. A lean engine on an xtype is from a vacuum leak. The reason it does it cold is the same reason you dont get out of cold water naked in front of women. The orings for imt's and intake shrink(smaller) when cold and the leaks are worse. Replace imt orings with jag green ones. You can heat shrink large heatshrink tubing(use the kind with glue) over brake booster check valve, and make sure you have the new style ribbed pcv hose. Then replace both upper and lower intake orings for the intake manifold..you dont need 02's

 

Thanks again Brutal. By way of an explanation, earlier trouble codes indicated an O2 sensor issue on bank 2. So based on that and mileage I ordered 2 upstream O2 sensors. That was before I joined this forum and maybe a mistake.
However, from the great info I garnered on this site I tried the easiest most logical thing first which was to clean the MAF sensor. It seemed logical at the time as after the install of a k&n filter and plug change mileage immediately dropped. Was not trying to go beyond your suggestions and will be replacing the IMT o-rings as well. Also, the heat shrink tubing idea.
As an update to my previous post cleaning the MAF was the issue.
No more miss at 2-3000 rpm. No more check eng light.
Mileage back to normal.
Would like to thank you again Brutal for your prompt response and expert advice.

 

thanks for the thanks. do a hard reset of the battery to clear learn adaptations when you fix everything. This will clear out long term fuel trims and other crap the ecu picks up trying to comphensate for a poor running engine.
Hard reboot is disconnect 1 battery cable(or bothm but not needed) touch the "disconnected" cables together to erase volatile memory of control modules.
And to answer the inevitable statements that come up...NO IT WONT FRY ANYTHING
and is 1 of the first things done after repairs like this as well as weird issues that crop up from time to time. especially with the new cars and over 30+control modules that do stupid crap just like your PC