CEL code P0174

[JBeezy]

System too lean bank 2. I've had this code since I installed the supercharger and had it tuned. Jeff told me when he finished the tune that I had a coil going bad on the driver side. I replaced all driver side coils with brand new Borg Warner coils to see if it would help. No change. Reinstalled my stock coils and it still runs the same. No change in either. Car has 52k miles now. Before the supercharger install and tune I didn't have this issue.

My car also has like a mist only when warmed up at idle. Drives and runs great when in drive. Only when in neutral. Sometimes if I let it idle long enough it will clear up, then 20 seconds later it starts again.

Any advice on this issue will be greatly appreciated. Thanks in advance

[camelgrundle]

Was the car running lean during the tune? I would take it back to the tuner and tell him you replaced the coil and let him have a go at figuring it out.

[martyo]

Can you PM me your telephone number?

[Limited360]

Look at your Long Term Fuel Trim's with the SCT handheld. If they are larger than X% they will set a fault. This can be either a bad O2 sensor, leak in the exhaust showing lean or possibly during closed loop operation the fueling / MAF transfer function may be off.

A lot can play into this. I would discuss it with the tuner.

[martyo]

If it's one bank it has nothing to do with a mass air transfer function.

The car needs to be datalogged. There are too many variables here to guess at.

In any event I sent you my number since I got no answer when I called. Call me when you have a chance.

[Limited360]

Maybe the other bank has not walked out the fuel trim all the way to set a code? In defense of my MAF statement.


Regardless data log is the correct answer.

[JBeezy]

At one time it triggered both banks. I reset it recently and just this one came up this time. Talked with Marty and Jeff
This morning. I'm going to take the car in soon for a fix and retune with the 4.0 pulley. Thanks again Marty

[martyo]

At one time it triggered both banks. I reset it recently and just this one came up this time. Talked with Marty and Jeff
This morning. I'm going to take the car in soon for a fix and retune with the 4.0 pulley. Thanks again Marty

My pleasure.

It was good to speak to you again today.

[Limited360]

At one time it triggered both banks. I reset it recently and just this one came up this time. Talked with Marty and Jeff
This morning. I'm going to take the car in soon for a fix and retune with the 4.0 pulley. Thanks again Marty

Sounds like a solution!

Both banks does lean more towards the tune needing correction, does it set the code if you let the car idle or does it do it while driving? Could be a multitude of things, however since both banks are setting lean then I would guess the closed loop calibration is off and just needs to be dialed in.

Just curious are you running a stock MAF or aftermarket? I know after I had dug into the calibration that was in my car for a trilogy with a 3.2" pulley, I have learned that the calibration was completely 'fudged'. The MAF transfer function was completely inaccurate only to get WOT fueling right, for the love of god it had a flat step change in it! The tune was asking for .65 LAMBDA at WOT when it was only delivering .73 LAMBDA... After a further deep dive this pointed out some of the drivability issues I had seen. Nothing like seat time in a car to find all the small issues.

I know they will take good care of you at the shop down there. Best of luck and report back the findings!

[JBeezy]

I want to say it sets codes when idling. I say this because that's the only time I have any issue. From time to time the idle will get crazy almost like it's skipping/missing then it clears up for a few. Then starts again. Once the car is put in gear it runs smooth as a new one. Drive ability is perfect.

I'm using a blow thru mass air. I also cleaned it just in case

[Limited360]

I want to say it sets codes when idling. I say this because that's the only time I have any issue. From time to time the idle will get crazy almost like it's skipping/missing then it clears up for a few. Then starts again. Once the car is put in gear it runs smooth as a new one. Drive ability is perfect.

I'm using a blow thru mass air. I also cleaned it just in case

Interesting. Definitely curious to see what the root cause is, always good to know for future reference.

I'd be interested to see a data log to see if its all short term fuel trims or if long term fuel trims are turned on too.

[Shankin]

The long term trims are turned on. It seems as though the car has a leak. We will find it and keep everyone up to date on the issue. Great speaking with you jbeezy! See you soon!

[Limited360]

The long term trims are turned on. It seems as though the car has a leak. We will find it and keep everyone up to date on the issue. Great speaking with you jbeezy! See you soon!

Air leak downstream of the MAF? Could point to the idle issues mentioned.

Sorry to be so nosey... always curious since my background is in Diagnostics.
:stupid:

[martyo]

Air leak downstream of the MAF? Could point to the idle issues mentioned.

Sorry to be so nosey... always curious since my background is in Diagnostics.
:stupid:

Possibly.

The blower was a customer self-install and we addressed some issues when the car came in and it is not always easy to tackle all the issues and send the car on its way in a single Saturday. With that said, we feel confident that when he brings the car back we will get it straightened out.

[Limited360]

Possibly.

The blower was a customer self-install and we addressed some issues when the car came in and it is not always easy to tackle all the issues and send the car on its way in a single Saturday. With that said, we feel confident that when he brings the car back we will get it straightened out.

Anytime a customer brings in a self install can lead to plenty of issues out of your hands that can't be seen in a day.

I know you will sort them out!!!

[martyo]

Anytime a customer brings in a self install can lead to plenty of issues out of your hands that can't be seen in a day.

I know you will sort them out!!!

Any install can have its share of problems, whether ours or a customers. The difference is when we do the install, we know what we did and where to look for the problem - that is not always the case with a customer self-install.

The good news is very few problems ultimately stump us. They may piss us off, but they rarely stump us. :P

[JBeezy]

Any install can have its share of problems, whether ours or a customers. The difference is when we do the install, we know what we did and where to look for the problem - that is not always the case with a customer self-install.

The good news is very few problems ultimately stump us. They may piss us off, but they rarely stump us. :P
I have no doubt they will get it figured out. It's not that big of an issue because other than that the car runs and drives flawlessly. Much credit to Mo's shop. I'm completely happy with it as is. Even with this minor issue. [emoji106]

[JBeezy]

If only you all could see the smile on my face. Had an awesome time at Mo's Speed shop. Car runs great. No CEL. Just smiles. Thanks again to Mo's Speed Shop for taking excellent care of me and my car. Special thanks to Marty and Jeff. I love that place.

I highly recommend Mo's for any car needs you may have. One stop shop. I even met a forum member there. CWright stopped thru. Pretty cool guy. Found out he only lives 30-45 minutes from me. His car is Bad Azz. Great way to spend a Saturday.

[JBeezy]

Just want to say thanks again. Drove back to Alabama and the car is flawless. Runs great. Idles great. I've been riding in the rain and this car never sees rain.

This thread can be closed

[Limited360]

What's was the problem?