Community Forums

Mystery · 04-12-2013, 09:03 PM

I have a 2002 Newmar Dutchstar with a 330 cat 3126 e and the oil pressure guage started fluxuating from 40 down to 0. The dash engine protection lights came on and I pull over and shut down. I went back checked oil level which showed full as I had all pm done 2000 miles ago and inspected engine and showed no leaks. I restarted and the oil pressure came back up to 40 and it ran great and took to cat service center. I was told it was a bad oil pressure sensor. I had oil analyzed and it was clean. (no metal in it). The cat dealer said there was no problem in driving it so we took it back out to our cabin and the alarm went off again and I went through same procedure and now guage is reading 40 now. Could shutting it down and restarting reset the alarm or guage? I did pull off cover in master bed room and inspected sensor and as I am short I could cram myself down between head and ecm and felt the sensor and it was firmly attached. All thoughts would be appreciated!

Mystery · 04-12-2013, 09:06 PM

Cat dealer did order new sensor to be installed this week. I have 70,200 miles on the rig and it is running well except for this issue.

Skip426 · 04-13-2013, 12:07 AM

I'm still learning all the ins and outs of Cat engines myself, but from what I've read about the way these engines build fuel pressure , if they don't have oil pressure they don't get enough fuel pressure to work the injectors and quit running. Probably the reason the Cat dealer said it was ok to drive.

Mystery · 04-13-2013, 08:16 AM

That was my first concern and cat service said heui pump was working properly and oil pump was working. They hooked a mechanical guage to it to test.

R2Home · 04-13-2013, 08:47 AM

What about a bad ground? Had that issue with a different Cat engine a while back. It was not in a MH but.....

Mystery · 04-13-2013, 07:17 PM

That is a good suggestion because it acted up after going over a series of railroad tracks. Thank you!

lilblueduce · 04-14-2013, 08:21 AM

First thing to check is the oil. Is it over full? 3116 and 3126 are prone to injector cup problems. The oil will smell like fuel and it will be real thin. Problly a ground or a gauge problem.

Mystery · 04-14-2013, 08:32 AM

Oil level is normal with no fluxuating between checks which have been frequent of late. Oil was tested and was in good condition. The oil pressure sensor looks to be a brass or bronze fitting with a plug on exterior end. I was surprised that the cat service center did not have one on hand and had to order as they are a busy center and it is a common engine. The alarm is just unnerving.

Mystery · 04-14-2013, 06:25 PM

Just arrived home from our cabin about 206 miles driven and guage worked perfectly! I got 8.5 mpg running the genny the entire way. Just dropped it back at cat service center for sensor? Gotta be a ground or wiring issue bc it acted up on Thursday night after going over a double set of rough railroad tracks.

swampdog2 · 04-18-2013, 05:28 PM

I had the same problem several years back ! I was sure the motor was going south on me but! it was a bad sending unit. put new one in and 70 thousand miles later it's just fine.