I have been getting P0101 whenever the weather changes, I realize that this could be the reason, but it didn't start happening til I had my tune tweaked by the shop that did it for me. Any suggestions on what to do with the tune to make it less sensitive to weather changes? My problems really only come up when it gets warmer and a little more moisture in the air. I had it throw P0101 four times in one ten minute drive. No boost leaks or anything like that, its all been checked. Ideas?

 

bad MAF

Map sensor failing ? Getting moisture on it?

Could be a boost leak that shows it's head under humidity/temp conditions.

Bad tune

Can be several things.

 

Have who ever tuned you take a look at your fuel trims. They could be way off. I'd do that before jumping to the conclusion of a faulty part.

 

I was wondering if this could be it. I have an interceptor, and fuel trims are one of the things I've noticed aren't quite right, but only under part throttle. They'll go waaaaay off like half or three quarters, but full throttle they're fine and just cruising they're good too. The weather part is what really gets me. It runs fine anywhere from like 25-45 F but as soon as it gets warmer it throws the code like once a mile.

 

What are the trims?

 

Well, I was watching them really really close today. Driving normal they are usually between -3.5 and +3.5 except for random instances where they go from -10 to +10 or sometimes as far as -16. Under full throttle they immediately go to 0 but around 5k they go to -10...so I am really starting to think this may be it.

 

Even though there definitely is room to dial in the part throttle trims a bit, they aren't horrible or unusual by any means for a dyno tune (although the -16 is a bit much for even a dyno tuned car unless the engine was about to enter into dcfo). For him to really really dial you in for part throttle accel/decel your best bet is to have the tune dialed in under normal driving conditions.... aka a "street tune".

As far as the full extent of the issues you're having.

Gather all the DTC's and post the codes to have something more to work off of

 

Its only the one code. Lol. P0101. And only when its warmer than about 45 degrees out.

 

Well, I was just outside and letting it run, got trims that at idle were at 17.8-18.9. They smoothed out a little bit after that, but were not great. It looks like I'll be going back up to the shop I got tuned at in the next couple days here to have them dial it in. Time for a street tune I guess.

 

Any rough idling?

 

Usually when I start my car it runs in a loop which holds the AFR at 14.7-14.9 until it warms a bit.

#1 clean the MAF with MAF cleaner, inspect the wires and make sure they aren't frayed or anything and plug it back in. Clear the code and see if that helps.

I have issues with my car whenever there is alot of humidity in the air. After it rains, or if its really foggy, my car runs super choppy. The MAF (in my car its in the lower CP) is reading turbulence due to the humidity in the air from what I can tell. The MAF sensor HZ throw my car so rich at WOT that it misfires until the car dies out again and I clean the MAF.

 

That's basically what is happening to me. My AFR is fine most of the time, yesterday I let it warm up and while it was idling my short term trims were the number I was talking about. I checked my MAF out yesterday before doing that and took apart my intake to make sure it looked all good, and my sensor looms brand new. I cleaned it just to be sure with the cleaner though and the results afterward were the -18ish numbers I posted. I've had issues with it not liking change in humidity, but never 5 MAF codes in one fifteen minute drive...and it consistently does it when the temp gets up a little or humidity goes up. I think it really just needs some tweaking. Today when I got to work I went through everything on my interceptor and just sitting in my parking spot my trims were at -11.5. No code today though because it was only 27 degrees out. Dumb thing. Lol.

 

I'll have to dig up some old logs to see what my STFT and LTFT is. But my tuning computer is not with me right now cuz I'm letting a friend borrow it for his car. You need to try and get a guy near you that has HP tuners to do a full datalog of the car. That will help out greatly. just a fuel trim here or there isn't really going to be enough information for many people on here to make a concrete judgement to be honest.

 

Lol.....



When a car is first started up on a file day it is in open loop. The ecm is going off the last saved.maf calibration +stft+ltft saved. So once added that's what it goes off of. The. Once in closed loop the car will watch the lambda and ect. so therefore trims will go up, down... If trims are far off it can cause a p0101 and other maf codes. But if it changes with weather like dry to humid or hot to cold. Watch for condensation.... It can hit the maf, and skew trims and.cause p0101s....

Typically with 10-15+ or 10-15 - trims, car will run horribly, and get kr everywhere. So please watch your foot. Get this taken care of.

 

I watch KR also, I get a little on going, but nothing I didn't get when on gms1. It all seems normal except my trims. No KR when all out. I cleaned my air filter for my k and n yesterday and checked my MAF and today it made it through warm weather with no code. I'm going to the shop tomorrow to have them datalog and fix my trims.