Greetings CRD fans...

New owner of an 06 KJ. New to the Liberty, but not to diesels or Jeeps.

Lots of you clean your MAP sensors. I've not done mine as yet, though plan to check it out on a warmer day...

Those who have cleaned theirs, what drivability changes were suffering from it being dirty, and what improvements or changes were noted after cleaning?? I had the GDE eco tune a week ago and am doing flips over the highway mileage Ive seen. (gps) High 30s and even into the low 40s on a 200 mile all cruise / 70 run. (may have had a tailwind helping there) Any way, If my MAP is dirty and contributing to these numbers, I don't want to ruin a good thing by 'fixing' it. (Been using premium diesel and additive also.)

Ive searched a bit but haven't found the before and after effects.

Thanks,
rr

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Cleaning the MAP should, if anything, improve your mpg... not lower it. That said, are you getting low 40s via EVIC? I have seen as high as 48mpg on there, so I wouldn't trust it too much... If I had my guess, driving at 70 mph you SHOULD be getting more like 32-33 with the GDE Tune.

Hello stoutdog. I dont have EVIC...

With truckstop diesel on my 800 mile drive home after purchase, I was averaging about 22. 70mph on cruise using garmin GPS for speed and distance. Rather disappointing, was hoping for 25 at least.

filled tank at my local station with 'premium' diesel on way to have tune loaded. On 175 mile drive, recorded 23mpg. Refilled to filler top.. Refueled at same station back home. 175 miles 4.007 gal. Freaked me out. Didnt believe it and figured i'd screwed something up or pump was inaccurate..

Few days later with same fuel source made a trip of 271 miles again at 70 2100 rpm apx on tach. refilled at same station to the filler top. 7.40 gal. thats 36.64 mpg.

So, if thats abnormally high, then i'm feeling pretty fortunate... I havent done much in town driving but that seemed really low. like 14mpg, although it was mostly short trips, engine barely had chance to warm up so .. so that probably makes sense. Ill know more with more certainty after driving it for a few months. Not sure why the mileage was lower than expected before tune or why higher after... I would have been happy to see 25-27

Another member here posted on an older thread (forget who or where, old navy thread?) Anyway, someone posted that after cleaning they actually lost 5mpg. perhaps MAP was damaged or something... Thats why I asked about map cleaning.

I have samco hoses to install next warm day we have here so ill see what my sensor looks like then too. Thanks for the link and feedback!

rr

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Hopefully I don't come across as doubting you or anything, I'm simply very very surprised.

Not at all. If it remains consistent I should ask GDE or some competent team to take the thing apart and see whats up.... No one is more surprised than myself! I only started to have some degree of confidence that I haven't made some stupid mistake after noticing the fuel gauge drop at a rate which would correspond to the figures. (gde tune supposedly made the gauge linear now) I fully expect to feel like an idiot at any point now... . Ill report back here with how Ive screwed up after a few more tanks... fwiw GDE was very suspicious as well.

At any rate... Im not going to touch a thing (map) for the time being...

cheers,
rr

I clean mine very oil change.

MAP Cleaning 101

VMKJCRD, Since you have the '06, what size allen wrench holds the MAP in place? The link above says that it's 4mm but mine is definately a different size (larger) and the sensor looks different than the one in the picture so it's probably an '05. I've cleaned mine before but I'm short on tools right now and need to go out and buy right size.

I have an '06 and it takes the 4mm allen wrench... Unless the previous owner actually messed with the MAP, lost the original bolt, and replaced it with a larger one, I'm not sure how you would have anything different. Presuming the current bolt is still for an allen wrench, just go to HD and get a full set of metric allens. They can be had for pretty cheap.

Boy do I feel stupid, after looking at some pictures of the MAP installation, I found I was trying to remove the wrong sensor. The one I was looking at was near firewall towards center left side of engine. I thought it seemed harder to get to than last time I cleaned it