Trouble Codes - Running Lean?

[Alfonso]

I bought my car with no CEL in October, and after about 500 miles of driving, the CEL popped up. I borrowed my friend's SCT Tuner for his V6 so I can read the trouble codes. I had to go emissions testing so I cleared the codes while I was at it. After another 500 miles of driving, the same codes popped up.

P1131 - lack of ho2s, 11 switches, sensor indicates lean (b1, s1)
P1151 - lack of ho2s, 11 switches, sensor indicates lean (b2, s1)

I'm pretty sure it's running lean because of light-colored smoke and lack of carbon build-up in the exhaust tips. I heard it could be a number of things besides bad o2 sensors, from vacuum leaks to a lack of a tune. I haven't touched anything since this problem occurred because of my lack of time and money being a college student. If someone were to give me a list of solutions starting from the most probable solution to the least, that would be great!

Engine Modifications:
JLT Performance Ram Air Intake
Accufab Twin 60mm Throttle Body
SLP Loudmouth II Cat-Back Exhaust
Kooks Long Tube Headers
Kooks Catted X-Pipe

Thanks,
Alfonso

[vertigyn]

Has the car been tuned? Our cars are infamous for running lean with just a CAI. My car had a catback and CAI when I got it and was running lean to the point it would turn itself off. Got a tune and it was all good from then on out.

[Alfonso]

I do not have a tune. The most I've heard from people is to get a tune or replace o2 sensors. Other things I've heard are to clean the MAF sensor and check for vacuum leaks. I just don't know where to start cause my wallet can only spend so much lol

[vertigyn]

Well, a tune can fix it all and make the car run better in general. I gained a good amount of HP and TQ after a tune on my car (something like 30hp and 40tq).

The tuner can see exactly what is going on - A/F mixture, what sensors are sending the codes and then can adjust accordingly. He can turn the sensors off if wanted as well - they don't really help with anything anyways - just emissions crap (we don't have that stuff in FL, so it worked for me).

[blown03Mach1]

checking for vacuum leaks will cost you about $5. Just buy you a can of carb cleaner and spray it around the intake manifold while the engine is running. If while spraying the cars idle picks up (because it is sucking in the cleaner) then you will know it is a vacuum leak and where it is at.

Suspect with the JLT and your LT's you are lean and need a tune.

[Alfonso]

Originally Posted by vertigyn

Well, a tune can fix it all and make the car run better in general. I gained a good amount of HP and TQ after a tune on my car (something like 30hp and 40tq).

The tuner can see exactly what is going on - A/F mixture, what sensors are sending the codes and then can adjust accordingly. He can turn the sensors off if wanted as well - they don't really help with anything anyways - just emissions crap (we don't have that stuff in FL, so it worked for me).

I'm highly considering a tune... Hopefully all is well after that.

Originally Posted by blown03Mach1

checking for vacuum leaks will cost you about $5. Just buy you a can of carb cleaner and spray it around the intake manifold while the engine is running. If while spraying the cars idle picks up (because it is sucking in the cleaner) then you will know it is a vacuum leak and where it is at.

Suspect with the JLT and your LT's you are lean and need a tune.

I doubt it's a vacuum leak though because the engine runs very smoothly; it's just showing the code and blowing white smoke.

I'll update after whatever I do to my car, thanks guys

[vertigyn]

How much white smoke are we talking about? Like just a little upon start up or a constant thing when the car is running?

White smoke is usually indicative of a coolant leak into the engine - not a good thing...
My car, for a bit, had a little smoke come out when starting and we believe it is just a little oil leak.

But those leaks don't really have anything to do with the lean codes.

[Alfonso]

There's very little white smoke, all the time. My exhaust tips barely have any carbon build-up compared to other cars.

[vertigyn]

Hmm, car shouldn't smoke like that (I don't think this is related to the tune/lean issue but could be wrong). Do your coolant levels remain constant? How about the oil?

[Alfonso]

Both coolant and oil levels are fine... Think I should just get a tune and see what happens? And will a tune get rid of the annoying rev hang...?

[vertigyn]

A good tuner can help with the rev hang but it might just be that you need a new IAC (Idle Air Control unit). Or just need to clean it with some carb cleaner.

http://www.mach1registry.org/forums/...ad.php?t=18330

A good tuner might also be able to give you some insight on the smoke. My tuner is very knowledgeable about all things Mustang - so he's always been able to answer my questions about most everything.

I don't know if you are anywhere near this: http://www.facebook.com/pages/Horsep...57464467620638

But Hermann did my first tune for the Mach and it was great. He is kind of pricey, though...so shop around too. Just make sure you trust whoever you go with and they have a good history/recommendations.

[Alfonso]

Isn't there more than to just cleaning the IAC? http://www.mach1registry.org/forums/...ad.php?t=18330

I was planning to get an SCT tuner... I called them and they said it could fix my problems but I feel like they only said it to get me to buy it lol

[vertigyn]

Originally Posted by Alfonso

I was planning to get an SCT tuner... I called them and they said it could fix my problems but I feel like they only said it to get me to buy it lol

Choose a tuner before buying a device. When I spoke of getting a tune - I meant, go get a custom dyno tune with a professional. The handhelds aren't that useful unless you know how to use them. Some tuners don't require them at all and tune directly to your ECU - which will save you some money by not buying a handheld tuner. Other tuners use SCT or Diablo and will require you to buy the one they use.

Call around, get quotes, ask questions.

[vertigyn]

As for cleaning the IAC, there's a mixed camp on that. It's a pretty cheap part so you could just go buy a new one and maybe it will fix your issue (I did this but it didn't solve my issue). To try and clean it, just remove it from the car (near the throttle body) spray it with carb cleaner, clean the TB while you are there (spray it - the blades, open it up and spray the inside of the housing around it) and put it all back together. Not hard at all.

[Alfonso]

Well the SCT tuner comes with a custom tune from them after receiving a mod list from the buyer... So I'm either getting that or spending more money for a pro tune at Excessive Motorsports in Manassas

[vertigyn]

A dyno tune is always superior but it comes down to the price difference and what you can afford at the time. With minor mods, it probably won't be much of a difference with the "e-mail tune" vs. the Dyno tune.

Does the tune that would come with the SCT include free updates? Say it doesn't fix your idle issue, will they tweak it and send you the new revised tune for free? Or if you change gears, will they fix that and send you the update?

[blown03Mach1]

Originally Posted by vertigyn

A good tuner can help with the rev hang but it might just be that you need a new IAC (Idle Air Control unit). Or just need to clean it with some carb cleaner.

http://www.mach1registry.org/forums/...ad.php?t=18330

A good tuner might also be able to give you some insight on the smoke. My tuner is very knowledgeable about all things Mustang - so he's always been able to answer my questions about most everything.

I don't know if you are anywhere near this: http://www.facebook.com/pages/Horsep...57464467620638

But Hermann did my first tune for the Mach and it was great. He is kind of pricey, though...so shop around too. Just make sure you trust whoever you go with and they have a good history/recommendations.

I thought Hermann was good stuff, but search the web and over the past year there have been numerous people talking about paying for work to be done and Hermann taking their money without completing the work....

Search around for details.

[vertigyn]

Originally Posted by blown03Mach1

I thought Hermann was good stuff, but search the web and over the past year there have been numerous people talking about paying for work to be done and Hermann taking their money without completing the work....

Search around for details.

Hmm, that would be sad...it was a long time ago when he worked on my car but he was top notch back then.

[blown03Mach1]

Originally Posted by vertigyn

Hmm, that would be sad...it was a long time ago when he worked on my car but he was top notch back then.

I know what you mean as I was surprised as well. I ahd always heard nothing but good stuff about hm.


It is on the net so I take it with a grain of salt.

[Alfonso]

Originally Posted by vertigyn

A dyno tune is always superior but it comes down to the price difference and what you can afford at the time. With minor mods, it probably won't be much of a difference with the "e-mail tune" vs. the Dyno tune.

Does the tune that would come with the SCT include free updates? Say it doesn't fix your idle issue, will they tweak it and send you the new revised tune for free? Or if you change gears, will they fix that and send you the update?

Yes, they do include free updates and free tunes. http://www.americanmuscle.com/x3-cus...er-9904se.html