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 Post subject: Re: 06 CRD REPLACEMENT MAP SENSOR -CHEAP-
PostPosted: Wed Dec 17, 2014 5:17 pm 
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thermorex wrote:
I can try swapping them since I have both and see how much mileage change 845 gives me. I'll set a reminder for tomorrow since today is impossible.


I guess you'd need to run at least a tank or two to get meaningful numbers, but I'd be very interested in the result of this experiment. I didn't realize you had both. I assume you have a pretty consistent commute / driving conditions, and some good baseline numbers?

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 Post subject: Re: 06 CRD REPLACEMENT MAP SENSOR -CHEAP-
PostPosted: Wed Dec 17, 2014 5:27 pm 
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SFHLibertyCRD wrote:
A follow-up. I quickly googled the part number and came up with this from a tuning site:

0 281 002 437 3 bar (20 kPa @ 0.4V , 300 kPa @ 4.65V)
0 281 002 845 3 bar (11 kPa @ 0.25V , 307 kPa @ 4.75V) This one is used in GM Stage 2 Sky / Solstice GXP upgrade kits sold by GM, i got this one from a forum member very hard to find for sale
0 281 002 456 3.5 bar (50 kPa @ 0.5V , 350 kPa @ 4.5V)

http://www.versatune.net/forum/viewtopic.php?f=5&t=260

Can anyone make sense of what, if any, differences there are? I haven't figured out how to do the calculation yet.



This holds true below if the data above is valid. You can use the data from each sensor as points on a line and work out the slope for each sensor.

The 437 seems to have a slope of 65.88
The 845 seems to have a slope of 65.78

The sensors should perform almost identical in the CRD.

Example at 1volt

437 should read 59.5 kpa
845 should read 60.3 kpa

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 Post subject: Re: 06 CRD REPLACEMENT MAP SENSOR -CHEAP-
PostPosted: Wed Dec 17, 2014 6:04 pm 
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GreenDieselEngineering wrote:
SFHLibertyCRD wrote:
A follow-up. I quickly googled the part number and came up with this from a tuning site:

0 281 002 437 3 bar (20 kPa @ 0.4V , 300 kPa @ 4.65V)
0 281 002 845 3 bar (11 kPa @ 0.25V , 307 kPa @ 4.75V) This one is used in GM Stage 2 Sky / Solstice GXP upgrade kits sold by GM, i got this one from a forum member very hard to find for sale
0 281 002 456 3.5 bar (50 kPa @ 0.5V , 350 kPa @ 4.5V)

http://www.versatune.net/forum/viewtopic.php?f=5&t=260

Can anyone make sense of what, if any, differences there are? I haven't figured out how to do the calculation yet.



This holds true below if the data above is valid. You can use the data from each sensor as points on a line and work out the slope for each sensor.

The 437 seems to have a slope of 65.88
The 845 seems to have a slope of 65.78

The sensors should perform almost identical in the CRD.

Example at 1volt

437 should read 59.5 kpa
845 should read 60.3 kpa


Thanks, Keith.

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 Post subject: Re: 06 CRD REPLACEMENT MAP SENSOR -CHEAP-
PostPosted: Wed Dec 17, 2014 7:10 pm 
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SFHLibertyCRD wrote:
thermorex wrote:
I can try swapping them since I have both and see how much mileage change 845 gives me. I'll set a reminder for tomorrow since today is impossible.


I guess you'd need to run at least a tank or two to get meaningful numbers, but I'd be very interested in the result of this experiment. I didn't realize you had both. I assume you have a pretty consistent commute / driving conditions, and some good baseline numbers?


I will try it, but based on what Keith just replied you, I doubt there will be a difference. And yes, I do have a relatively consistent commute, I'll swap it tomorrow and leave it for few tanks.

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 Post subject: Re: 06 CRD REPLACEMENT MAP SENSOR -CHEAP-
PostPosted: Wed Dec 17, 2014 7:13 pm 
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thermorex wrote:
SFHLibertyCRD wrote:
thermorex wrote:
I can try swapping them since I have both and see how much mileage change 845 gives me. I'll set a reminder for tomorrow since today is impossible.


I guess you'd need to run at least a tank or two to get meaningful numbers, but I'd be very interested in the result of this experiment. I didn't realize you had both. I assume you have a pretty consistent commute / driving conditions, and some good baseline numbers?


I will try it, but based on what Keith just replied you, I doubt there will be a difference. And yes, I do have a relatively consistent commute, I'll swap it tomorrow and leave it for few tanks.


Yes, based on what Keith said I decided to cancel my order for a 437 for the time being. Nonetheless, will be watching to see what you find, if anything.

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 Post subject: Re: 06 CRD REPLACEMENT MAP SENSOR -CHEAP-
PostPosted: Thu Dec 18, 2014 1:48 am 
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GreenDieselEngineering wrote:
0 281 002 437 3 bar (20 kPa @ 0.4V , 300 kPa @ 4.65V)
0 281 002 845 3 bar (11 kPa @ 0.25V , 307 kPa @ 4.75V) This one is used in GM Stage 2 Sky / Solstice GXP upgrade kits sold by GM, i got this one from a forum member very hard to find for sale
0 281 002 456 3.5 bar (50 kPa @ 0.5V , 350 kPa @ 4.5V)quote]


This holds true below if the data above is valid. You can use the data from each sensor as points on a line and work out the slope for each sensor.

The 437 seems to have a slope of 65.88
The 845 seems to have a slope of 65.78

The sensors should perform almost identical in the CRD.

Example at 1volt

437 should read 59.5 kpa
845 should read 60.3 kpa


Good stuff, and as I suspected - this is what I started last nite on the way to factoring the slopes, using the WINDOWS Scientific Calculator - since I'm only good for single-digit numbers, I got lost and went to bed with a headache:

Factoring the scaling on the 437 MAP sensor against the 845 MAP sensor

437 MAP 20kpa = 2.90psi/0.40v ..... 300kpa = 42.50psi/4.65v
845 MAP 11kpa = 1.60psi/0.25v ..... 307kpa = 44.50psi/4.75v

(456 MAP 50kpa = 7.50psi/0.50v ..... 350kpa = 50.80psi/4.50v, for comparison)

437 MAP = 3bar x 15baro = 45psi max ..... low 2.90psi min output = 0.40v ..... hi 43.50psi max output = 4.65v

845 MAP = 3bar x 15baro = 45psi max ..... low 1.60psi min output = 0.25v ..... hi 44.50psi max output = 4.75v
so press and volts scaling has wider spread than 437 MAP

437 MAP sensor scaling 4.65v-0.40v = 4.25v span ..... 42.50psi-2.90psi = 39.60psi span ..... 39.60/4.25 = 9.3176 psi\volt ..... 1.0v/9.1376psi = 0.1073v/psi

845 MAP sensor scaling 4.75v-0.25v = 4.50v span ..... 44.50psi-1.60psi = 42.90psi span ..... 42.90/4.50 = 9.5333 psi\volt ..... 1.0v/9.5333psi = 0.1049v/psi

Alternately, figuring 0-45psi range and 0-5v scaling ..... 45psi/5.0v = 9 psi/volt ..... 1.0v/9psi = 0.1111v/psi

437 MAP 42.50x0.1111 = 4.72v max
845 MAP 44.50x0.1111 = 4.94v max

Not even the same, so the P/V scaling differs for each MAP sensor, which will offset ECM calculations for fuel\air ratio -
GDE indicates the 437 and 845 MAP sensor calibrations are close enuff to be compatible in the KJ system

IMO, it is safe to replace the oem 437 sensor with the revised 845 sensor, as per GDE's input

FYI, that GM part # 55206797 does show to be the BOSCH 845 MAP on eBay - BOSCH and 845 can be clearly seen on the label

The GM 845 sensor runs ~$30 on eBay, usually with free shipping

on EDIT:

Verify the BOSCH number B4 installing:

OE KJ 05140331AA - BOSCH # 0 281 002 437

Repl 68031593AA - BOSCH # 0 281 002 845 - GM part # 55206797

Thanks to all who contributed part numbers and info, allowing this excercise in provable reliable compatibility

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Last edited by gmctd on Thu Dec 18, 2014 2:05 pm, edited 4 times in total.

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 Post subject: Re: 06 CRD REPLACEMENT MAP SENSOR -CHEAP-
PostPosted: Thu Dec 18, 2014 9:18 am 
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Ordered one today

http://www.ebay.com/itm/GM-OEM-SENSOR-5 ... 98&vxp=mtr

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 Post subject: Re: 06 CRD REPLACEMENT MAP SENSOR -CHEAP-
PostPosted: Thu Dec 18, 2014 11:53 am 
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Now people are ONLY ordering one for what reasons?

Is their current one skewed or failed?

"Maintenance" purposes?

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 Post subject: Re: 06 CRD REPLACEMENT MAP SENSOR -CHEAP-
PostPosted: Thu Dec 18, 2014 1:02 pm 
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ArmyChief wrote:
Now people are ONLY ordering one for what reasons?

Is their current one skewed or failed?

"Maintenance" purposes?


One reason could be, the MAP sensor housing is thermoplastic, as are all the other sensor modules - at 10yrs of age, having been subjected to repeated cycles of heat\cooling, the plastic is becoming non-compliant, brittle - which means that the simple act of removing the sensor for cleaning can crack\break the module - even a crack across the body can render it non-functional, useless

At only 30bucks, it might not be a bad idea to have one available on-hand at incidence of removal\cleaning, 'n'est ci pa?

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'05 CRD Limited
Pricol EGT, Boost
GDE Hot '11; EDGE Trail switched
SEGR; Provent; Magnaflow;
Suncoast T\C, Transgo Tow'n'Go switch;
Cummins LP module, Fleetguard filter, Filterminder
2.5" Daystar f, OME r; Ranchos; K80767's, Al's lifted uppers
Rubicons, 2.55 Goodyears
Four in a row really makes it go


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 Post subject: Re: 06 CRD REPLACEMENT MAP SENSOR -CHEAP-
PostPosted: Thu Dec 18, 2014 1:05 pm 
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gmctd wrote:
ArmyChief wrote:
Now people are ONLY ordering one for what reasons?

Is their current one skewed or failed?

"Maintenance" purposes?


One reason could be, the MAP sensor housing is thermoplastic, as are all the other sensor modules - at 10yrs of age, having been subjected to repeated cycles of heat\cooling, the plastic is becoming non-compliant, brittle - which means that the simple act of removing the sensor for cleaning can crack\break the module - even a crack across the body can render it non-functional, useless

At only 30bucks, it might not be a bad idea to have one available on-hand at incidence of removal\cleaning, 'n'est ci pa?


Yes, I guess it could be so.... :)

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 Post subject: Re: 06 CRD REPLACEMENT MAP SENSOR -CHEAP-
PostPosted: Sat Dec 20, 2014 2:14 pm 
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Wow interesting to read all this tech stuff. But it is funny That our Liberty had the 845 in it. and the paper work showed the previous owners had all the work done at a dealership. So I do not think anybody ele had changed it before and as nasty as it looked I doubt if anyone ever pulled it and cleaned it.

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 Post subject: Re: 06 CRD REPLACEMENT MAP SENSOR -CHEAP-
PostPosted: Sat Dec 20, 2014 6:01 pm 
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canonoch1 wrote:
Wow interesting to read all this tech stuff. But it is funny That our Liberty had the 845 in it. and the paper work showed the previous owners had all the work done at a dealership. So I do not think anybody ele had changed it before and as nasty as it looked I doubt if anyone ever pulled it and cleaned it.

Without in-depth responses from everyone that has ever cleaned or replaced the MAP in the '05-'06 KJ, I would have assumed that all are like my '05, 437 - at the first mention of the 845, I would then need to research the 845 for any compatiblilty with mine, which would also require research for 437 base comparison - it's how we prevent creating more troubles than those we are endeavoring to resolve - numbers usually do not lie

And, thanks again to all who contributed

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SEGR; Provent; Magnaflow;
Suncoast T\C, Transgo Tow'n'Go switch;
Cummins LP module, Fleetguard filter, Filterminder
2.5" Daystar f, OME r; Ranchos; K80767's, Al's lifted uppers
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 Post subject: Re: 06 CRD REPLACEMENT MAP SENSOR -CHEAP-
PostPosted: Sun Dec 21, 2014 12:13 pm 
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Have had an 845 sitting on the shelf for over a year now for our '05. Will look forward to hearing if it proves to be an upgrade over the 437.

Thanks to everyone, as always, for all the effort.

DOC

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 Post subject: Re: 06 CRD REPLACEMENT MAP SENSOR -CHEAP-
PostPosted: Sun Dec 21, 2014 4:22 pm 
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From my notes, the numbers, as gmctd so eloquently put: "Numbers do not lie"!
If they are flawed, let me know, Excel made a mistake. :ROTFL:

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)

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

using the above numbers for 845 unit: kPa/mv/psi
bottom of sensor range
11.00 kPa 0.25mv 1.595415115psi
100.00kPa 1.603040541mv 14.50377377psi
175.00kPa 2.743243243mv 25.3816041psi
200.00kPa 3.123310811mv 29.00754755psi
250.00kPa 3.883445946mv 36.25943443psi
300.00kPa 4.643581081mv 43.51132132psi
307.00kPa 4.75mv 44.52658548psi
top of sensor range

whole lot of numbers between these, but you get the point
the difference between 4.65mv & 4.75mv is ~60kPa or 8.75psi at the very top of the range which I do not think one would ever get there. The difference in curves would be slightly in the 845's units favor as the millivolt signal going to the OBC would be at a slightly higher value at any given point across the entire operating range of the sensor. The higher the boost, the slightly higher mv signal the OBC would see.... How this offset affects fuel injection rate and other things I am not sure....
:roll:

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 Post subject: Re: 06 CRD REPLACEMENT MAP SENSOR -CHEAP-
PostPosted: Sun Dec 21, 2014 4:58 pm 
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Realizing that numbers always been bery bery bad to me, still, something glares out at me:

GDE indicates:
The 437 seems to have a slope of 65.88 (which your calcs seem to verify, if this is same as Scalar A)

The 845 seems to have a slope of 65.78 (which your calcs give as 279.5555528, assuming Scalar A, again)

I'm likely unaware\missing something, but it does beg for explanation B4 I get a headache...........

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'05 CRD Limited
Pricol EGT, Boost
GDE Hot '11; EDGE Trail switched
SEGR; Provent; Magnaflow;
Suncoast T\C, Transgo Tow'n'Go switch;
Cummins LP module, Fleetguard filter, Filterminder
2.5" Daystar f, OME r; Ranchos; K80767's, Al's lifted uppers
Rubicons, 2.55 Goodyears
Four in a row really makes it go


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 Post subject: Re: 06 CRD REPLACEMENT MAP SENSOR -CHEAP-
PostPosted: Sun Dec 21, 2014 8:27 pm 
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WWDiesel wrote:
From my notes, the numbers, as gmctd so eloquently put: "Numbers do not lie"!
If they are flawed, let me know, Excel made a mistake. :ROTFL:

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)

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

using the above numbers for 845 unit: kPa/mv/psi
bottom of sensor range
11.00 kPa 0.25mv 1.595415115psi
100.00kPa 1.603040541mv 14.50377377psi
175.00kPa 2.743243243mv 25.3816041psi
200.00kPa 3.123310811mv 29.00754755psi
250.00kPa 3.883445946mv 36.25943443psi
300.00kPa 4.643581081mv 43.51132132psi
307.00kPa 4.75mv 44.52658548psi
top of sensor range

whole lot of numbers between these, but you get the point
the difference between 4.65mv & 4.75mv is ~60kPa or 8.75psi at the very top of the range which I do not think one would ever get there. The difference in curves would be slightly in the 845's units favor as the millivolt signal going to the OBC would be at a slightly higher value at any given point across the entire operating range of the sensor. The higher the boost, the slightly higher mv signal the OBC would see.... How this offset affects fuel injection rate and other things I am not sure....
:roll:


While I can't explain it mathematically, my "gut" tells me the first line of the following is correct, but the other lines are way off. Keep in mind this was stuff I pulled from a website, and the scalars and offset do not seem to make sense with the specifications as listed in the top line. I would trust Keith @ GDE on this one as opposed to the numbers below the first line below:

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)

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Purchased 68k 09/13 | Build 01/05
GDE FT Eco Tune | Blue Samcos | Bosch 5v GPs | 2nd Gen Fuel Head | New Bosch MAP | Hayden Fanclutch | New TB kit ~74.2k (Geordi)
Tow Package | Engine/Tranny/TC Skids | Fumoto F102S | Roof Rack | USA Spec PA-11CHR | EVIC | auto dimming mirror | Yoko Geolander A/T-S LT225/75R16


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 Post subject: Re: 06 CRD REPLACEMENT MAP SENSOR -CHEAP-
PostPosted: Mon Dec 22, 2014 1:30 pm 
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SFHLibertyCRD wrote:
WWDiesel wrote:
From my notes, the numbers, as gmctd so eloquently put: "Numbers do not lie"!
If they are flawed, let me know, Excel made a mistake. :ROTFL:

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)

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

using the above numbers for 845 unit: kPa/mv/psi
bottom of sensor range
11.00 kPa 0.25mv 1.595415115psi
100.00kPa 1.603040541mv 14.50377377psi
175.00kPa 2.743243243mv 25.3816041psi
200.00kPa 3.123310811mv 29.00754755psi
250.00kPa 3.883445946mv 36.25943443psi
300.00kPa 4.643581081mv 43.51132132psi
307.00kPa 4.75mv 44.52658548psi
top of sensor range

whole lot of numbers between these, but you get the point
the difference between 4.65mv & 4.75mv is ~60kPa or 8.75psi at the very top of the range which I do not think one would ever get there. The difference in curves would be slightly in the 845's units favor as the millivolt signal going to the OBC would be at a slightly higher value at any given point across the entire operating range of the sensor. The higher the boost, the slightly higher mv signal the OBC would see.... How this offset affects fuel injection rate and other things I am not sure....
:roll:


While I can't explain it mathematically, my "gut" tells me the first line of the following is correct, but the other lines are way off. Keep in mind this was stuff I pulled from a website, and the scalars and offset do not seem to make sense with the specifications as listed in the top line. I would trust Keith @ GDE on this one as opposed to the numbers below the first line below:

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)


Yep - I just been Wikipedia'ed, so scalar now has meaning, intent, purpose, and scope - the 'official' 845 numbers appear unreliable at this admittedly limited educational juncture - I'll therefore go with accepting GDE's input and WWDiesel's scalar slope (which I attempted but got lost, with a headache), which has by now become a vector by defining the psi vertical and mv horizontal |/

Also, those scalar numbers are not in millivolts, but are in volts
0.25mv would be 0.00025v, actually is 250mv, 0.250 volts
4.75mv would be 0.00475v, actually is 4750mv, 4.750 volts

These BOSCH map sensors are scaled 0.000-5000mv, zero to full-scale
BOSCH ECM input circuitry is scaled for 0.000-5000mv

Ain't edumacashun wunnerful???

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'05 CRD Limited
Pricol EGT, Boost
GDE Hot '11; EDGE Trail switched
SEGR; Provent; Magnaflow;
Suncoast T\C, Transgo Tow'n'Go switch;
Cummins LP module, Fleetguard filter, Filterminder
2.5" Daystar f, OME r; Ranchos; K80767's, Al's lifted uppers
Rubicons, 2.55 Goodyears
Four in a row really makes it go


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 Post subject: Re: 06 CRD REPLACEMENT MAP SENSOR -CHEAP-
PostPosted: Wed Feb 04, 2015 11:22 pm 
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Posts: 19
I just read this whole thread.... and my head hurts now

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05 Jeep Liberty CRD

2" OME lift
30x10.5-15 Goodyear Wrangler MT/R tires
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Green Diesel Engineering ‘Hot’ tune
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and so much more


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 Post subject: Re: 06 CRD REPLACEMENT MAP SENSOR -CHEAP-
PostPosted: Wed Jul 29, 2015 8:58 am 
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Location: Green Cove Springs FL
gmctd wrote:
papaindigo wrote:
Just to rain on the debate a bit per my previous post "the factory MAP senor on my 05 and my son's 06 are both the Bosch 0 281 002 437 which can be found online for about $70-$90 based on the Bosch PN" and MrMopar64 originally said that DCJ used the 845 on "newer" engines but did not specify what that meant. Could be the 07 and later VM 2.8 but I'm just guessing.

Regardless if PN68031593aa is the most recent DCJ PN for the 05/06 KJ CRD then that part appears to be the 845 and idParts has them for ca. $25.

In any case even if the "electronic" debate, which I don't pretend to understand, is valid (I presume it is) and there is some upper end boost limit (could be) as a practical matter those owners using the 845 have not reported any issues.


845 would have increased upper limit in the '05s, maybe matching the '06s

Could be important that some have reported fuel mileage increase after replacement - if proven, that would be reason enuff to rush rite out and replace the 437, no matter what condition it is\was in - even if the original was crudded up, as noone reported substantial gains after cleaning\reinserting


I may have uncovered a problem with using the 845 sensor.

For the last couple months I have been using a Yeti Stage 2(free) tune and the Bosch 845 MAP sensor. Power and boost have been great but have noticed a significant drop in MPG and heavy amounts of black smoke when accelerating from a dead stop.
It was the heavy black smoke that concerned me.
It didn't take much to create that smoke either, just light to moderate acceleration from a dead stop or just rolling at 5 mph.
The only way to keep the black smoke from happening was to just ever so lightly press on the accelerator pedal.
Boost pressure, as read using TorquePro, would max out at 22.3 psi under moderate acceleration at any speed.
Once moving at a good rate, I could accelerate with no heavy black smoke.

I checked the turbo actuator and vacuum lines and solenoids and all are functioning normally.
Boost hoses and intercooler are tight with no leaks.
It just seemed that the ECU was dumping too much fuel without adequate boost and therefore producing a heavy thick cloud of black smoke.

So I switched back to the OEM 437 MAP sensor and the black smoke has been significantly reduced. Max boost, as read using TorquePro, is now 21.3 psi and I have to push the accelerator pedal a little bit harder to get it there.

It seems that, with this tune at least, the difference in the two sensor calibrations is enough to fool the ECU into thinking that the turbo is producing more boost than it actually is.
Stock tunes may not have any noticeable effect.
Or maybe this was just a fluke and the 845 sensor I was using had some weird problem.
All I know is that the difference is significant.

I dont know if this MAP sensor change will effect my MPGs. I have worked through multiple engine issues lately so only time will tell.

_________________
Bought my '05 CRD on June 2nd '07, used with 29,000 miles.
intake elbow and EGR delete. 5 volt bosch glow plugs
Yeti stage 2 ECU tune. Straight pipe exhaust. DIY intercooler hoses
Provent and modified factory 180F thermostat
Replaced cylinder head (cracked) at 160,000 miles + ARP studs
2.5 inch lift, JBA upper arms, 235-85-16 tires.
Still love it.


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 Post subject: Re: 06 CRD REPLACEMENT MAP SENSOR -CHEAP-
PostPosted: Wed Aug 26, 2015 4:02 pm 
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Joined: Sat Sep 13, 2008 7:34 am
Posts: 200
Location: Rochester, NY
gmctd wrote:
papaindigo wrote:
Just to rain on the debate a bit per my previous post "the factory MAP senor on my 05 and my son's 06 are both the Bosch 0 281 002 437 which can be found online for about $70-$90 based on the Bosch PN" and MrMopar64 originally said that DCJ used the 845 on "newer" engines but did not specify what that meant. Could be the 07 and later VM 2.8 but I'm just guessing.

Regardless if PN68031593aa is the most recent DCJ PN for the 05/06 KJ CRD then that part appears to be the 845 and idParts has them for ca. $25.

In any case even if the "electronic" debate, which I don't pretend to understand, is valid (I presume it is) and there is some upper end boost limit (could be) as a practical matter those owners using the 845 have not reported any issues.


845 would have increased upper limit in the '05s, maybe matching the '06s

Could be important that some have reported fuel mileage increase after replacement - if proven, that would be reason enuff to rush rite out and replace the 437, no matter what condition it is\was in - even if the original was crudded up, as noone reported substantial gains after cleaning\reinserting


I have searched online and cannot find a supplier as yet. Everything I find is overseas.... Anyone know a current supplier?
Thanks,
Jim

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Jim

2005 Liberty Sport Stone White
SAMCO Hoses
Provent
HHO System
In-line thermo
'95 Moto Guzzi California 1100

I learn more from my struggles than that which comes easy......
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