The 2 most common snesors that give incorrect readings...

[Rawze]

Here are the 2 sensors for the CM871, CM2250, and CM2350 engines that seem to have the biggest impact on fuel mileage. Sad part is, they will hardly ever throw a fault code.

[in2trux]

Average cost less than 1 hour at Cummins ($153)

[Rig Wrench]

I've had an issue with my 871, on its third imap sensor in 90k miles. It will be fine, then have no manifold pressure, then jump back to normal. It will do this back and forth until I replace the sensor. Mine is the only one in the fleet givin an issue. Anyone ever have similar problem? Maybe a fluke?
Thanks

[Pro Star Cummins]

Hello, Could it be a wiring issue, short or bad ground ?

I could be wrong , parts made in Mexico and such.

[1096]

I had 37 counts on my Exhaust Pressure. I pulled the tubing running to it first and found it completely plugged. I replaced the tubing and have not had a problem since. I have not changed the Sensor yet.

[Rawze]

(02-18-2016 )Rig Wrench Wrote:  I've had an issue with my 871, on its third imap sensor in 90k miles. It will be fine, then have no manifold pressure, then jump back to normal. It will do this back and forth until I replace the sensor. Mine is the only one in the fleet givin an issue. Anyone ever have similar problem? Maybe a fluke?
Thanks

I would examine one closely and see if it is getting contaminated with something.



The pressure part of the IMAP sensor is up inside the head of the unit (as shown in the pic). This means it will clog with soot long before the "cage-looking" part of it clogs up. The pressure sensor itself is also a capacitive sensor, and solvents will partially short it out, making it read incorrectly. I.E.> Cleaning one with solvents will usually make it read wrong. There is no way to properly clean it - It is better to simply replace it when it starts getting clogged up.

Tags:

imap sensor, imap pressure part, intake pressure sensor, imap capacitive sensor

[Kenworth2012]

(02-18-2016 )in2trux Wrote:  Average cost less than 1 hour at Cummins ($153)

For both or each??

[Rawze]

(02-19-2016 )Kenworth2012 Wrote:  For both or each??

that sounds like the price for both. The IMAP is usually only about $50 bucks give or take.

[in2trux]

Price was for both.