MAF/ORM Mod, Use Caution, Transmission shifting problems

got boost · **Joined:** Sat Oct 15, 2011 10:34 am **Posts:** 3

This is not to knock anyone's expertise on this website. I have found this forum to be filled with valuable knowledge. However, I must share my recent experience with the MAF sensor disconnect mod. I disconnected this sensor approximately 2-3 months ago and all was fine. I recently started having some transmission shifting issues (hard shifts and not shifting into overdrive). I tried troubleshooting myself and could not diagnose problem. I took the CRD into a well respected transmission shop and explained the problem. I left the Jeep there and within an hour I get a phone call from the technician. He asked if the vehicle had been worked on by anyone lately and related he found the MAF sensor disconnected. I explained to him I disconnected it and that should have nothing to do with the transmission. What I was told next shocked me and made me feel very stupid. I cannot begin to repeat his technical jargain, but basically the MAF sensor does have a job when it comes to making the transmission shift properly. He plugged the connector back in, cleared the error code and the Jeep is shifting smoothly again. I was relieved because I went in thinking I was gonna need a new transmission-$3500.00 I left paying a very modest service fee and was happy and embarrassed. I asked why it didn't start shifting poorly when I first disconnected the sensor and he explained to me the computer was making compensation for it, but it eventually couldn't compensate anymore. He was more thorough than that with his explanation, but again, I cannot repeat his technical jargain. Lesson learned. I'm glad there are still honest mechanics out there and will recommend this one to everyone I know. Point is, not all modifications are good ones.

4x4kingx889 · **Joined:** Sun Jul 17, 2011 6:42 pm **Posts:** 235

Strange I had mine done for about 6 months and I have been noticing the same problems

RJM · **Posted:** Wed Jan 18, 2012 9:20 pm

You have been mis-informed.

spitfire36o · **Posted:** Thu Jan 19, 2012 10:05 am

Mistake number 1: Taking the word of a "trained technician" over time tested proven information on this forum.

Rabert · **Posted:** Thu Jan 19, 2012 10:31 am

I also believe you have been misinformed and suspect you will get the transmission problem again.....and here is why. I was having a P0714 code with the trans going into limp mode. Here is what I tried before replacing the Control Solenoid Assy;

Replaced trans fluid and filters
Installed the inline check valve in trans return line,
Uninstalled inline check valve in trans return line,
replacing new fuel head with spankin new fuel head;
installed lift pump,
designed, installed auto bleed at fuel head,
ran with and without MAF and FCV unplugged,
bypassed factory trans cooler with aftermarket,
bought cheapo code reader and resetting everytime in limp mode
installed lift kit :lol:

Out of all of this, none of the mods listed above made a difference in the behavior of the transmission. After replacing the tranny control solenoid, fluid, and filters problem solved! I am currently running with factory cooler bypassed, MAF unplugged, FCV unplugged, auto bleed circuit installed, lift pump "bangin" and no I did not remove the lift kit :lol:

I would suggest getting the code the TCM or ECM was reporting and keep asking for help on this forum. Thrust me this forum is "super" and the the CRD folks are even better. Hang in there it can be fixed.

Quiksilver · **Posted:** Thu Jan 19, 2012 10:35 am

hmmmm....

I don't think this is correct :JEEPIN:

had mine unplugged for about 20 000km and didn't have this issue at all.

Cause and effect - it worked fine after he cleared the codes/reset the computer.

RJM · **Posted:** Thu Jan 19, 2012 11:06 am

The MAF sends a signal to the ecm to control the EGR and FCV not the tranny, it has its own TCM.If your tech. is making you feel stupid run the other way! although you payed a modest fee you still got hosed, and chances are the problem still exists.

Rabert · **Posted:** Thu Jan 19, 2012 11:16 am

Let me clarify something: Based on my experience with troubleshooting "limp mode", I do not think unplugging the MAF will cause Got Boost's problem. Sorry if I mislead anyone. Also, my CRD would run great after clearing the code for up to week at a time. Thanks!

tjkj2002 · **Posted:** Thu Jan 19, 2012 11:20 am

The MAF sensor can make a trans act funny after time.Just because yours has not done it yet does not mean it can't happen.Do a little research,GM has a TSB for this very same issue and the cause is most caused by oiled airfilters messing up the MAF and it does cause a bucking trans.

got boost · **Joined:** Sat Oct 15, 2011 10:34 am **Posts:** 3

I don't want to offend anyone's expertise and the technician did not say the MAF controls the tranny. He just explained that Chrysler uses the MAF sensor to make adjustments and calculations which then get sent to the computer to be used for all sorts of functions, including the transmission. If the transmission starts to act up again I will post my findings. I just wanted to put the info out there in case anyone has had the same experience.

Squeeto · **Posted:** Thu Jan 19, 2012 1:30 pm

got boost wrote:

I just wanted to put the info out there ....

Appreciated.
Let us know how this turns out.
Welcome to LOST

Quiksilver · **Posted:** Thu Jan 19, 2012 2:41 pm

Squeeto wrote:

got boost wrote:

I just wanted to put the info out there ....

Appreciated.
Let us know how this turns out.
Welcome to LOST

X2 - lets hope it did fix the issue.

Question, are you running any scan readers while you are driving and how old is the battery in your truck?

grywlfbg · **Posted:** Thu Jan 19, 2012 4:24 pm

Conversely, I have a GDE tune, MAF is plugged in, and I'm getting hard shifts (no codes though). Have replaced the fluid and filters and dealer did a "quick learn". Jeep is shifting fine now but I'm keeping my eye on it (it's been ~ 2 weeks).

got boost · **Joined:** Sat Oct 15, 2011 10:34 am **Posts:** 3

Quiksilver wrote:

Squeeto wrote:

got boost wrote:

I just wanted to put the info out there ....

Appreciated.
Let us know how this turns out.
Welcome to LOST

X2 - lets hope it did fix the issue.

Question, are you running any scan readers while you are driving and how old is the battery in your truck?

No scanners and the battery is an optima, less than 2 years old. Strong battery.

kccrd · **Joined:** Thu Mar 08, 2007 10:35 pm **Posts:** 267

So far my 05 MAF has been unplugged since December of 06 and now at 165k no problems, I just change the tranny fluid and the two filters about every 30k so far so good.

nursecosmo · **Posted:** Fri Jan 20, 2012 9:15 pm

tjkj2002 wrote:

The MAF sensor can make a trans act funny after time.Just because yours has not done it yet does not mean it can't happen.Do a little research,GM has a TSB for this very same issue and the cause is most caused by oiled airfilters messing up the MAF and it does cause a bucking trans.

The GM MAF sensor issue is completely unrelated to the OP's transmission issue. Some early to mid GM Gas models use the MAF signal to regulate transmission line pressure. The CRD Liberty's TCM does not incorporate the MAF signal in any way for transmission parameter regulation.

Troy, if you want to follow your own advice and do a little research, look up Bulletin No.: 04-07-30-013B

Unfortunately got boost, you have been mislead about the cause of your shifting issue. However, no one here knows what caused the problem and results can't be argued with. If your tranny guy was able to fix the problem and only charged a moderate fee, I'd say that you made out well.

CRD-DAN · **Joined:** Mon Oct 10, 2016 2:54 pm **Posts:** 27

I'm having the same symptoms. Hard shifting and no overdrive. I'm having a real hard time getting solid info on the possible cause. Anyone have any ideas or know of a thread with the answer ?

flash7210 · **Posted:** Sat Apr 15, 2017 8:22 am

CRD-DAN wrote:

I'm having the same symptoms. Hard shifting and no overdrive. I'm having a real hard time getting solid info on the possible cause. Anyone have any ideas or know of a thread with the answer ?

Your transmission is in limp mode.

Scan for codes. You should at least have a P0700 code.
Check fluid level. It should be at the full-hot mark.
Clear the codes to see if shifting returns to normal.

WWDiesel · **Posted:** Sat Apr 15, 2017 12:58 pm

If you have your MAF unplugged to prevent EGR operation, and you are having transmission shifting problems, you may want to plug it back in and install either an EGR Block OFF Plate or install a Weeks Elbow Kit from SasquatchParts.com!

If the MAF or ECM provides a control signal to the TCM from the MAF, it is not divulged in any of the FSM information pages or in any of the wiring diagrams... :roll:

MAF/ORM Mod, Use Caution, Transmission shifting problems

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