p0174 Lean Bank 2?

[9BABCobra8]

I have replaced TPS sensor,
cleaned MAF sensor,
replaced PCV,
IMRC's are clean,
changed fuel filter,
new spark plugs,

maybe replaced the EGV?

no cats or O2 sensors due to X-Pipe

 

[LDC2335]

i have it too, got mine around the time i changed plugs and wires, maybe coincidence though. i cleaned maf again yesterday, and tightened throttle body, thinking i might have had a leak, drove it twice today and no light yet(knock on wood)

 

[9BABCobra8]

The car has a slight hesitation that has developed from 2K-3.5K, not sure why or what is causing it....
the weird thing is... it only does it when the car warms up. On a cold start and drive it runs like a champ...

car does have 125,000 miles. i know the plug wires are aftermarket though replaced around 80,000 miles... I'm running out of ideas to fix/change... Im going to take a look at the MAF again... but the temp. issue throws me off

 

[tt54l32v]

cheack for vac leaks and which o2's are gone the upstream or downstream

 

[02silverstang]

been there also with my 99 cobra for 6 mo did all the same things you guys did . mine turned out to be the lower and upper intake gaskets were shot after getting frustrated and replacing everything that was the only thing i had not replaced . also replced the air bacum control behind the intake . hope this help you guys out .

 

[9BABCobra8]

Thanks for the help guys, I'll get back with you and let you know...

 

[Goindeafonmtx]

Wierd. Two threads in one day with the same code. So I'll say the same thing. Its the upstream o2 sensor on the bank it is calling lean.

And you have o2 sensors. Stock, your car has two sets. Sounds like you just turn the downstream sensors off with the addition of a catless midpipe.

 

[9BABCobra8]

Wierd. Two threads in one day with the same code. So I'll say the same thing. Its the upstream o2 sensor on the bank it is calling lean.

And you have o2 sensors. Stock, your car has two sets. Sounds like you just turn the downstream sensors off with the addition of a catless midpipe.

So replace it and see? Good thing these are cheap... LOL

 

[tt54l32v]

no last thing to change is the 02, swap from side to side if anything. but you prob have a vac leak

 

[milktasd2]

I have that code and PO171. Cleaned the EGR, checked the CAI, Maf, and TB for leaks.

Whats the best way to check for an intake leak?

 

[venom1997]

if its a p0174 which means driver side im wondering how it could be a vac leak? but if you have the 171 and 174 both sides then it usually is a vac leak. A dirty maf usually throws one side and usually the 174 according to doing searches for p0174 on mustangs

 

[venom1997]

with it being an 02 code in closed loop it has no affect on WOT since its open loop i believe:shrug: some one correct me if im wrong. It should not cause driveability problems either, at least mine hasnt( i also have the p0174) i feel no difference in power or drivibility with the cel on or off:shrug:

 

[02silverstang]

if you get the p0174 and p0171 yes youre car will run like crap mine did and gas milieage sucked as well . and the best way to check upper and lower gasket leaks is to check the gasket and see if the center rubber part is worn mine wasnt that noticible till i was tidies in checking it . the good thing is all parts are under 40 bucks except for the egr mine was 65 i think .

 

[LDC2335]

ran it bout 20 miles today with no light, normally i would be on by now so mabye tightening the throttle body, or cleaning the maf with brake parts cleaner is working for me...

i finally found a damn throttle body gasket that fits, turns out the 96 and 97 are different? at least they are when you are buying a tb gasket.. i have a 96 with a 97 throttle body.

note: my tb gasket is broke, i wouldnt go messing with yours too much unless youve messed with it lately.

 

[Slow95Cobra]

vac. leak, low fuel pressure... depends on the baro of the MAF, but thats not common

 

[9BABCobra8]

Ran some more tests this week.
Running with-in fuel pressure spcs 32ish at idle and peaks arouns 43lbs.
checked plugs, car seems to be running a little rich but compression of all cylinders are with-in 7lbs of each other around 170. Still running strong at 126,000 miles.
just do not understand why the car only acts up when it warms up. Was told that the issue feels more like a misfire. checking in on the plug wires but the issue to me would be more constant...

 

[venom1997]

Ran some more tests this week.
Running with-in fuel pressure spcs 32ish at idle and peaks arouns 43lbs.
checked plugs, car seems to be running a little rich but compression of all cylinders are with-in 7lbs of each other around 170. Still running strong at 126,000 miles.
just do not understand why the car only acts up when it warms up. Was told that the issue feels more like a misfire. checking in on the plug wires but the issue to me would be more constant...

I wonder if a missfire could cause that code?

 

[DTB]

This code just popped up n my car 2. Dunno why. Maybe a loose o2 sensor?

 

[9BABCobra8]

I would think that a missfire would cause the sensor to read rich... but "What do I know, I'm just a Doctor." LOL sorry just throwing that quote in there. Seemed to work..

 

[tt54l32v]

I would think that a missfire would cause the sensor to read rich... but "What do I know, I'm just a Doctor." LOL sorry just throwing that quote in there. Seemed to work..

no a miss will make a o2 read lean because it only reads combusted o2.

if you had both lean codes i would check your maf