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06 CRD REPLACEMENT MAP SENSOR -CHEAP-
http://www.lostjeeps.com/forum/phpBB3/viewtopic.php?f=5&t=74785		 Page 5 of 6
Author:  jmoomaw [ Wed Aug 26, 2015 4:21 pm ]
Post subject:  Re: 06 CRD REPLACEMENT MAP SENSOR -CHEAP-
http://www.crateenginedepot.com/3-Bar-M ... 10930.aspx

Just ordered two sensors and two O-rings....$53.00 including shipping from the mid-west to NY...
Author:  geordi [ Wed Aug 26, 2015 7:15 pm ]
Post subject:  Re: 06 CRD REPLACEMENT MAP SENSOR -CHEAP-
Idparts.com carries them... As for the black smoke issues, I'd try swapping a new sensor in if it wasn't smoking like that before, sounds like a buggy sensor to me.

Boost upper limit should be 24-25 psi with over boost codes at 26+... At this range, the two sensor types have performed identically for me.

edit - fixed a bad autocorrect.
Author:  jmoomaw [ Fri Aug 28, 2015 6:50 am ]
Post subject:  Re: 06 CRD REPLACEMENT MAP SENSOR -CHEAP-
I took it in for a new timing belt and ended up replacing the turbo after 210,000 miles. Will change the sensor and then go from there if the smoking doesn't stop. Should arrive today!

I am getting to the point where $2,500 a year in maintenance is looking more than the heavy service use I put it through (pulling a mid size trailer and snow plowing my own two small parking lots).

Jim
Author:  Steevo [ Fri Aug 28, 2015 10:23 am ]
Post subject:  Re: 06 CRD REPLACEMENT MAP SENSOR -CHEAP-
I too am running an 845 sensor from Crate Engine Depot and Yeti tune (although I am running a Mild tune). My MPGs have not dropped since installing the sensor. I do notice a tad more black smoke than before if I really punch it from a stop, but I have attributed this to the Weeks EGR kit. I agree with Geordi regarding a faulty sensor.
Author:  geordi [ Fri Aug 28, 2015 1:47 pm ]
Post subject:  Re: 06 CRD REPLACEMENT MAP SENSOR -CHEAP-
Actually, I think the mild smoke is probably more to the Yeti mild tune than the elbow kit. I've installed a bunch of these elbows, they don't cause smoke. The first Yeti mild tune was yesterday, and after painting their driveway black (old soot in the exhaust) and fogging a road the first time I nailed it... It has settled down to only a bit of smoke on heavy throttle (floored) and nothing the rest of the time.

YMMV obviously, but I think the next thing I will be looking at is modifying the stock map just to eliminate the DTC and leave it at that. These things have a ton of power after they get done being worked over, no sense in overdoing it to the point of reducing economy.

Then again - a mild tune and keeping your foot out of the loud pedal might be a way to increase the economy anyway.
Author:  Silverbullet [ Mon Dec 14, 2015 12:49 am ]
Post subject:  Re: 06 CRD REPLACEMENT MAP SENSOR -CHEAP-
Just wanted to share I cleaned my 05' CRD MAP Sensor today. I used mass airflow cleaner and qtips.

Here are some before and after pictures. Hoping to get some gains in the MPG. I am holding 25.4 with the wife driving daily.

Image

Image

Wish I could have cleaned it more, too scared to damage it. For a new sensor at $25, I may just replace at some point.

Here is the link for a new sensor if someone stumbles on this post. Assuming I did not break during cleaning process, i wont need a new one.

http://www.amazon.com/gp/product/B008Y9 ... IPWJENITBW
Author:  WWDiesel [ Mon Dec 14, 2015 8:05 am ]
Post subject:  Re: 06 CRD REPLACEMENT MAP SENSOR -CHEAP-
Replacement MAP sensors are available for less than $20 bucks on line.... :wink:
Google this GM Part No. 55206797
They work fine in our Jeep CRD's, some have been running this one for several years now!

example: http://www.gmpartsdirect.com/oe-gm/55206797
Author:  apardo001 [ Tue Mar 13, 2018 9:57 am ]
Post subject:  Re: 06 CRD REPLACEMENT MAP SENSOR -CHEAP-
Bump! for the interest of those who are running the cheaper 845 map.

Opposed to some statements found on this thread, both sensors appear to have the same functional pressure range (20-300 kPa / 0,4 - 4,65 V). However, they do have different temperature sensor, used by ECU to read intake air temp.

Temperature measuring ranges:
837 reads 130 to -40 C
845 reads 130 to -20 C

Datasheets found:

http://www.finjector.com/verkkokauppa/documents/5226302185a2a/0281002437.pdf

http://www.motec.com/filedownload.php/?docid=5134

I tried both sensors on a cold 25 C morning and got this IAT readings using Torque app.
437: 26 C
845: 30 C

Now we just need to calibrate the IAT maps on the ECU to read correct temperature with the 845 sensor, this should not be a big impact to performance or economy, but my OCD wins :mrgreen:

Will post any progress.
Author:  WWDiesel [ Tue Mar 13, 2018 2:29 pm ]
Post subject:  Re: 06 CRD REPLACEMENT MAP SENSOR -CHEAP-
That's interesting; thanks for posting. :shock:
Have you calculated the voltage deviation differential over the full range?
Author:  apardo001 [ Tue Mar 13, 2018 11:31 pm ]
Post subject:  Re: 06 CRD REPLACEMENT MAP SENSOR -CHEAP-
Temp sensor is not linear, and the sensors seem to follow different curves, this makes is hard to calculate the differential. For the ECU, A 0,5 V change can mean 10 degrees on cold temperatures but only 5 on the hot side.

However, when testing both sensors, I see that using the 845 sensor makes IAT to be 15 degrees more when 837 sensor reads around 50 C, but only 5 degrees more when 837 reads 25 C. Also, using the 845 sensor makes IAT to change more rapidly.

Car seems to run exactly the same with both, but I'm not a dyno...
Author:  mrhemi [ Fri Mar 30, 2018 6:00 pm ]
Post subject:  Re: 06 CRD REPLACEMENT MAP SENSOR -CHEAP-
I see this temperature range discrepancy being a potential problem, especially when operating in a cold (Canadian) climate. However, I can not be sure how the IAT is being utilized in the fuel curve computation. I replaced my MAP sensor with an 845 last fall and over the course of the winter, have noticed a drop in mileage. based on the curves for the 437 vs 845 sensor, if I was operating at a true -20C IAT the 845 would be sending the ECU a -40C signal. That is a significant error at winter temperatures. The error diminishes as typical summertime temperatures are experienced. I think I will reinstall a 437 sensor and compare results. Note: I drive this CRD 1200km per week over the same route, I will have accurate results to compare.
Author:  mrhemi [ Sat Apr 14, 2018 3:42 pm ]
Post subject:  Re: 06 CRD REPLACEMENT MAP SENSOR -CHEAP-
Update: As promised I have some results to report on experienced performance difference between an "845" MAP sensor and the stock "437" expensive MAP sensor.

Measure ambient temperature and pressure readings between 845 and 437. sensors were left sitting side be side on the intake overnight to equalize temperature soak as much as possible.

Ambient temp. - 41F
Ambient Press. - 30"Hg

Each sensor was plugged into the harness and the live data was read with an Innova scanner.

"845" sensor, temp. - 37F
press. - 29.5"Hg

"437" sensor, temp. - 41F
Press. - 31.5"Hg

That is a bit of a difference on the temperature and the press. but as I stated earlier, I am not sure what the temp. signal is actually used for. The stock "437" MAP sensor was off on the press. which was what led me to change it in the first place. However, I noticed a consistent decrease in fuel mileage after doing so.

The "437" MAP sensor was reinstalled and now has four, 350 mile trips completed. Calculated mileage came in at 30.5, 31.0, 31.0 & 32 mpg, @ 75mph. Previously, with the "845" MAP sensor, mileage was consistently 27 - 28mpg over the same route and conditions.

I will agree the the less expensive "845" MAP sensor does function, but it appears to give up efficiency, especially in cold climates.

I have procured two "437" MAP sensors (one for each CRD) from Summit Racing for $66.00 each. Still pricey but far better than Chrysler. They will be installed this weekend. For the amount of driving I do with one of the CRD's that difference adds up.
Author:  joelukex4 [ Mon Apr 16, 2018 11:26 am ]
Post subject:  Re: 06 CRD REPLACEMENT MAP SENSOR -CHEAP-
mrhemi, where are you located? I can't touch that mpg except in the dead of summer. Right now highway mileage at 75 - 80 mph is about 26 - 27 mpg. I live north however, Chicago & Wisconsin.
Author:  mrhemi [ Mon Apr 16, 2018 2:13 pm ]
Post subject:  Re: 06 CRD REPLACEMENT MAP SENSOR -CHEAP-
I meant to include that the mileage figures are in Canadian gallons, as I am located in SW Ontario, about 5 hrs. east of Chicago. So your 27mpg would be 33.7mpg Canadian. (US gal. x 5) / 4 = Can. gal. So your numbers are comparable or better than what i calculate. Which MAP sensor do you have installed? My whole point in the comment was that I noticed a drop in mileage when I installed the "845" sensor. Reinstalling the original "437" sensor appears to have brought the mileage back up to what it used to be after four 300+ mile trips. Now this past weekend I just installed a brand new "437" sensor and noted that the ambient temperature and pressure readings were both accurate. I have done one 300+ mile trip, but it was through the ice storm covering the Mid-West and Central Canada, so 300 miles into a 30-40 mph headwind and four wheel drive the whole way didn't lead to good fuel economy.
Author:  TURBO-DIESEL-FREAK [ Tue Apr 17, 2018 1:00 am ]
Post subject:  Re: 06 CRD REPLACEMENT MAP SENSOR -CHEAP-
BUMP
Author:  WWDiesel [ Tue Apr 17, 2018 11:05 am ]
Post subject:  Re: 06 CRD REPLACEMENT MAP SENSOR -CHEAP-
The differences you are seeing may simply be well within the acceptable allowed deviation by the manufacturer? Without knowing what Bosch's +/- allowable standard deviation standards are, it will be hard to compare sensors based on reading inputs alone.
Only true way to compare different sensors would be to bench test their readings and compare values against certified calibrated instrument standards for both barometric pressure and temperature over their full range of operation.
I do find it odd that you found that much difference between the two units you read, but without having a greater amount of sensors available to establish some sort of baseline readings of which to be able to compare against, one of your units may simply be a faulty sensor and its readings are outside of its respective allowable deviation standards specifications... :shock:

I am no expert on this; I do have information on file for the two sensors and someone who has an instrument test background may understand some of these numbers and their comparative pressure/voltage relationship curves over their respective operating ranges? There are slight differences in their curves I am sure...

0 281 002 845 3 bar (11 kPa @ 0.25V , 307 kPa @ 4.75V)
Bosch 3.0 Bar T-Map Sensor / 0 281 002 845
Scalar A - 279.5555528
Scalar B - 0.23529412
Offset - 5.44444 (repeating)
using 65.7777 as the first multiplier, 1 as the second multiplier, and 5.4444 as the offset/additive.
= 11.0 kPa at 0.25v, 300.4219 kPa at 4.65v, and 306.9997 kPa at 4.75v

0 281 002 437 3 bar (20 kPa @ 0.4V , 300 kPa @ 4.65V)
Bosch 3.0 Bar T-Map Sensor / 0 281 002 437
Scalar A - 65.88
Scalar B - 1
Offset - 6.353
Author:  mrhemi [ Tue Apr 17, 2018 11:50 am ]
Post subject:  Re: 06 CRD REPLACEMENT MAP SENSOR -CHEAP-
I am an I&C Commissioning Engineer, so yes to the instrument testing background. The difference in the temperature curves between a 437 and 845 sensor is significant, specifically at lower temperature ranges, however, I do not know what the ECM is actually using the temperature signal for. My ambient measurements were taken with test equipment, not the weather channel. I did not have the means to run up the barometric pressure at the time. If I had the fitting used to pressure test the CAC and hoses, I could utilize that to run up the manifold pressure and record the pressure readings. As I stated earlier, I suspected the original 437 sensor was faulty as it read 2"Hg + high, that is why I replaced it with a 485 sensor, not realizing the difference in temperature curves. I now have two new 437 sensors, each installed in one of my CRDs. The pressure and temperature readings were identical at ambient. I complete the same 300 mile trip twice each week, so I will get additional mileage numbers with the new sensors.

I should add that the pressure curves 437 & 485 sensors posted by WW Diesel are vary similar, probably not enough to make much difference, but the temperature curves posted somewhere else in the thread, or available online, are quite different in the lower temperature range.
Author:  WWDiesel [ Tue Apr 17, 2018 2:02 pm ]
Post subject:  Re: 06 CRD REPLACEMENT MAP SENSOR -CHEAP-
mrhemi wrote:
however, I do not know what the ECM is actually using the temperature signal for.

I believe your statement is very important and most likely key to understanding how the differences in the temperature curves could impact the performance of the two sensors and just how much?
I wonder if GDE could provide any insight into how the temperature input impacts the fuel curves, boost, or anything else it might be used for? :roll:
Author:  wetherellak [ Tue Apr 17, 2018 9:57 pm ]
Post subject:  06 CRD REPLACEMENT MAP SENSOR -CHEAP-
jmoomaw wrote:
http://www.crateenginedepot.com/3-Bar-MAP-Sensor-55206797-P10930.aspx

Just ordered two sensors and two O-rings....$53.00 including shipping from the mid-west to NY...


I wish i could do the same, $34 to ship $45 worth of parts to AK. Post Office Flat Rate Shipping would only be $10. Oh well, keep looking...the trouble with living in a foreign country.


Sent from my iPhone using Tapatalk
Author:  mrhemi [ Wed Apr 18, 2018 8:15 am ]
Post subject:  Re: 06 CRD REPLACEMENT MAP SENSOR -CHEAP-
I contacted Keith regarding the pressure discrepancy I initially was concerned about, asking for an explanation of the control philosophy. Didn't get into the temperature question at the time. Regarding the pressure discrepancy he told me if it is not out enough to through a code the ECM is happy. I did not actually get into an explanation of the control philosophy.
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