Author Topic: Possible Map Sensor fault  (Read 29878 times)

Offline gunni

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Re: Possible Map Sensor fault
« Reply #15 on: March 08, 2010, 11:37:28 pm »
250kpa = 150kpa gauge = 1.5bar boost
Or about 20psi

Offline Tony C

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Re: Possible Map Sensor fault
« Reply #16 on: March 08, 2010, 11:48:03 pm »
thank you gunni,
thats fine then as not going over 8psi of boost on the engine due to the comp ratio,

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Offline dnb

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Re: Possible Map Sensor fault
« Reply #17 on: March 09, 2010, 12:53:21 am »
You should be able to sort the MAP sensor out yourself if you have a solder removing tool.
It will need setting up, but don't worry too much about that until you're aiming to do some proper tuning with the new engine.

It should handle 1 bar (14.7 PSI) of boost with a reasonable amount of headroom.

Offline Tony C

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Re: Possible Map Sensor fault
« Reply #18 on: March 09, 2010, 02:41:45 am »
cheers dave, going to un bolt the map from the board once i have removed the silicone sealer around the nuts etc,
will then desolder the sensor ready for the new one,
i flippin hope this cures it,

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Offline MWfire

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Re: Possible Map Sensor fault
« Reply #19 on: March 09, 2010, 03:38:48 am »
btw did you check if you have 5v on pin 3 of map sensor?

Offline Tony C

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Re: Possible Map Sensor fault
« Reply #20 on: March 09, 2010, 03:54:36 am »
errrrrrrr nope,
nobody said :D
which one is pin 3?
as can rig the ecu up in doors on a battery to test it,

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Offline Tony C

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Re: Possible Map Sensor fault
« Reply #21 on: March 09, 2010, 11:45:44 pm »
Right had a look with test meter tonight and this is the results
all pins have 0 volt reading except these two:


is that correct?
and is that the right pin for the 5volt?

does this confirm a dead map?

and reading on laptop


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Offline GintsK

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Re: Possible Map Sensor fault
« Reply #22 on: March 10, 2010, 02:00:50 am »


does this confirm a dead map?


Not fully.
You can get 100% when 0.06V pin is desoldered (or cut). Then map sensor readings will be foating.
Shorted to 0V MT should show offset value from basic settings (10). Shorted to 5V MT should show offset+range (10+250=260). Then it means MAP is dead, board is good.

Gints

Offline Tony C

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Re: Possible Map Sensor fault
« Reply #23 on: March 10, 2010, 02:03:50 am »
cut the 0.06v pin,
and conect it to one of the 0v pins?
then the 5.0 volt pin,
and read what it says in MT
or am i reading this wrong :D
« Last Edit: March 10, 2010, 02:13:25 am by Tony C »

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Offline GintsK

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Re: Possible Map Sensor fault
« Reply #24 on: March 10, 2010, 02:28:05 am »
cut the 0.06v pin,
and conect it to one of the 0v pins?
then the 5.0 volt pin,
and read what it says in MT
or am i reading this wrong :D
Almost right! :)
Not the leg of sensor, but pad of board. Leg at this time should be disconnected from board.

Offline Tony C

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Re: Possible Map Sensor fault
« Reply #25 on: March 10, 2010, 02:30:05 am »
Ok will do this in a moment,
thanks for the help,
will report back,

Vems Ecu, Twin Plenum efi and N2o
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Offline Tony C

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Re: Possible Map Sensor fault
« Reply #26 on: March 10, 2010, 03:30:53 am »
looking at this pic:


if you short the pad to either of these 3 pins on the left the kpa gauge jumps erraticly,
if you short it to the pin between the 5 volt and the cut pin the kpa gauge reads 12.3kpa,
when you short the pad to the 5volt pin the gauge reads 261.8kpa

Vems Ecu, Twin Plenum efi and N2o
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Vems Firmware: V1.1.74

Offline GintsK

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Re: Possible Map Sensor fault
« Reply #27 on: March 10, 2010, 04:12:54 am »
Left three pins are unused - erratic readings are expected.

Your board is OK, but Map - dead.

How about frozen moisture inside MAP? Could be?

Gints

Offline Tony C

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Re: Possible Map Sensor fault
« Reply #28 on: March 10, 2010, 04:16:44 am »
possible, but if so first time its happened in 5 yrs :-(
the map is now off the board, them solder suckers are a nifty bit of kit aint they :D
will let you all know how it goes once the new map arrives,

whats the best thing to use for sealing the bolts etc to the board,
i removed some hard type silicone stuff, will normal silicone sealer be ok?
or do i need something special????

Vems Ecu, Twin Plenum efi and N2o
13.314 @ 104.39 mph (10/06/07 3.9 v8)
Sponsored by: www.caprisport.com & www.interpart.biz
Web site: http://www.capriracing.co.uk

Vems Firmware: V1.1.74

Offline dnb

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Re: Possible Map Sensor fault
« Reply #29 on: March 10, 2010, 04:52:11 am »
Hot melt glue is my weapon of choice.

I'm inclined to believe the frozen water idea.  It's been pretty cold recently after all.