Sick Cummins N14+ in Rexburg Idaho

[strawdog]

Heading out of Montrose Co on a Friday morning, en route to Montana & places in between, the Volvo started having issues. We stopped in Rifle (~100 miles from Montrose) in 100-degree temps. Decided to proceed, too hot to sit.

 

Stopped at a turnout, intake manifold temps in the 120’s. An approximate 6% uphill climb, 120+ degree intake temp, and the engine started bogging down, no operation over 1500 RPM.

 

Continued to have problems in the lower gears for the next 15 miles or so, with error codes & the caution light on the dash. Error codes were Cylinder 4 – Low Injector Current and Cylinder 4 – High Injector Current, OK which is it?

 

Spent the night in an abandoned weigh station & after discussing, decided to head for the closest diesel repair shop, which happened to be in Rawlins, WY. Engine ran fine, error codes inactive, intake temp never over the mid 80’s.

 

Appointment with Wyoming Diesel was less than productive. He suggested the problem may be an anomaly because of the high temperatures, & it may not ever happen again, plus some talking which ended with they just weren’t interested in working on it. Hmmm and a Cummins dealer at that.

 

Left Rawlins with an anticipated 270-mile travel day. All went well for the first 225 or so miles, then began climbing. Error codes & caution light came back on with intake temp climbing into the mid 90’s. Engine in derated mode again Rev limited, pulled over 4 miles from the Salt River Pass summit – about 5 hours of driving time.

 

Up at 5 AM, on the road at 6 AM headed for Rexburg, ID. Engine ran fine, cool of the day, running intake temps low to mid 80’s max. ONE 7% grade for 3 miles, one 6% for two miles, an endless stretch behind a lady who insisted on driving 15 miles under the speed limit (no matter what it was) double yellow lines curvy up and down with her brakes on at every curve.

 

Booked a week here to do research & look for another diesel shop because – of course – you can’t work on vehicles in this RV park.

 

Sooooo-

 

• Engine runs good early in the day as long as intake temps stay below the 90’s while driving.

• Once intake temps start going above 90’s ECM gives Low Injector Current Cylinder #4 and derates operation limiting RPM’s.

• All other engine parameters look good, coolant temp, oil temp, etc.

 

Dave and Renee

 

 

 

[Alie&Jim's Carrilite]

I'd start with the obvious, AIr filter clean or unclogged?  If you have the ability to look at the codes it threw and look up potential causes that create the issue, you might be able to track the cause.

[DesertMiner]

Fuel filters?  I know.... but they can cause some strange symptoms to appear that seem to have nothing in common. How are you monitoring your intake temp?

[porky69]

Try one of the truck dealers/shops on I-15 at exit 113. There is Freightliner, Peterbilt , Volvo, Schow's (general repair shop), etc.

May possibly be injector, injector harness or pass-thru connector issues but that is just a WAG.

You may find that some repair shops are reluctant to work on something that is hard to replicate in the shop. ie High ambient temperatures and engine loads. Especially for a non-commercial customer.

That being said if you find a shop with a Cummins guru in it they will have no issues fixing it. Years ago I had a Peterbilt 379 with an N-14 Select that would derate momentarily (just like you turned the key off and back on) under load, randomly.  The "Laptop Mechanics" at 5 other Cummins authorized service centers (including our local Cummins dealer) threw handfuls of sensors and wiring fixes at it as the computer kept saying faulty sensors and never got it. Issue was particularly bad one July day passing through Greeley, Co and decided to have the Peterbilt dealer there look at it. Described the issue to the service writer and he said sounds like you a job for our "Cummins Guru", he's kinda busy but I will go talk to him and see what kind of timeline he has. A few minutes later he comes back out of the shop with a tech right behind him and says take me to your truck. Out we go, he opens the hood reaches behind the frame beside the starter, fishes out a fuse holder, replaces a blown fuse and says heres a couple of extra fuses and have a good day! Turns out somebody thought it was wise to put a fuse in one of the engine grounds and when it blows (he said very rarely, but it does happen) it causes the ECM to think a sensor failed and logs a code and temporarily derates the engine. He had seen it before, that time he said took many hours of searching to diagnose, but had hunch with mine and got me fixed in 10minutes. I gladly paid the minimum charges (0.5hr labor plus associated charges) and went on my way.

[Wrknrvr]

 Now Dave I see you are hugging your N14 also.

 

 Several years ago I had a rather frustrating trip with mine overheating and detrating  the engine. No codes showing. We made it to a small truckstop in northeast Utah.

 

 Ok now what ??? got up in the am and started the truck. Only 10 psi in the air system. Stuck a air governor on the truck. Fixed it.

 

 The Cummins shop in Kalispell did not understand why the air problem acted as it did. Air pressure was just a little low as compared to what the new governor was controlling. My fan came on at a higher temperature that it should,

 Now last fall my fan stuck on on our trip south. So installed a new air valve for the fan. Heck now it comes on sooner than it did before and keeps the temperature lower.

 

 Several years ago I install a new throttle position sensor while sitting in the North Ranch. Truck runs better with better throttle response. Since we bought the truck back in 2007 the cruise was always behind in staying up with speed then it would really pull the throttle down to get up to speed. Now the cruise works as it should.

 

 I will think about your situation,.  Vern

 

  look up Terry Chron on YouTube .  Very interesting person.http://www.heavydutypowertrain.com/

[Wrknrvr]

    Call if needed as I hugged my N14 a few times on the road.

 

 Terry Chron will talk to you if needed. His number is on his website.

   Safe Travels,.   Vern

[Wrknrvr]

 Is your fan kicking In as it should. Also something I have learned is to replace the fuel seliniod if you have 500000 miles on the seliniod.

 

 Maybe find a place where you could drive the truck to work on it.

 That is from Terry Chron on YouTube .

 

  Safe Travel,.   Vern

[strawdog]

First off a simple question… How does cummins number the cylinders? Is #1 at the front of the truck or the back? I’ve looked at every page of the service manual and couldn’t find it, firing order yes but numbering no.

 

Another input – looks also like I may be chasing a bad ground, a couple of times while driving the low air alarm beeper would start beeping even though air gauges were showing good pressure. Walked outside a few minutes ago and the damn thing was beeping WTH truck turned off, key not even in the ignition!!!!

 

Vern – talked to Terry Chron on the phone a couple of days ago, his first sugestion was pull valve cover and check injector wiring so that will require a place that will allow me to work on the truck.

 

Thanks everyone for the inputs, keep them coming. Will be pushing toward some simple stuff, until someone comes around and tells me I can’t have the hood up. This is an ideal place if I can pull it off, truck is in the shade almost all day!

Dave

[strawdog]

With the tension of the problem I didn't think of logging the engine parameters while driving so I could get a better feel of what was going on when the error code shows up. Will be logging every minute while engine is running now!

Edit: one of those crappy problems where the thing will run fine for maybe 5 or so hours then derate until it cools down, once it starts throwing the code it stays until the block cools.

Dave

 

[Darryl&Rita]

Check battery voltage. This latest symptom sounds like ours, last fall. 1 battery failed, and caused all kinds of random fault codes, until the low air alarm went off while sitting. Replaced batteries, and had an uneventful return trip. 

[Wrknrvr]

 As Darrlt said ,,,,, clean all battery connections. Grounds and even on alternator

 

 and test batteries 

 

 Vern

[strawdog]

1 hour ago, Darryl&Rita said:

Check battery voltage. This latest symptom sounds like ours, last fall. 1 battery failed, and caused all kinds of random fault codes, until the low air alarm went off while sitting. Replaced batteries, and had an uneventful return trip. 

Hmmmm... working on that now, all are a little low, 12.41,12.41, 12.42, and 12.41. going to charge them up one at and a time and check after sitting for awhile...

Dave

[Twotoes]

My brother lives in Rexburg. Its a small town. You may find a shop in Idaho Falls just south of Rexburg.

[strawdog]

2 minutes ago, Twotoes said:

My brother lives in Rexburg. Its a small town. You may find a shop in Idaho Falls just south of Rexburg.

Thanks, looking them over while doing what I can here, hard to get a shop interested when it might take several hours of driving for the codes to show up.

Dave

 

[lockmup68]

Turney Truck Repair in Dillon, MT, they saved my bacon on Saturday. Super honest and helpful. Wouldn't even charge me extra for opening up on a Saturday to get me back on the road. And Mr. Bob at the KOA made room for the trailer and even came and hooked up to it on side of road and towed it back to the campground. Wouldn't even let me buy dinner for him. 

[strawdog]

Well at least I found the cylinder numbering.... Page 125 of the shop manual.... "The cylinders are numbered from the front end of the engine".

Dave

[JPL]

Strawdog    I am following you close cause I've got a 98 610 w/n14. 580k. Hope you can get it fixed without spending an arm and a leg. Good luck and God Bless.     Pat

 

 

The Old Sailor

[noteven]

I’m very rusty on N14 mystery issues from when they were first in service  .... but I do remember they very much like healthy, well grounded DC volts supplied. 

Good advice being given to do some simple power supply csi...

I had a repair done at Kenworth Sales in Idaho Falls. They are just off the highway from Rexburg. Made a mistake doing a valve set and caused myself an oil leak. They got me in promptly etc. 

For “some reason” there are lots of old Kenworths working in the area. They may have a N14 person or two around...

They aren’t $41 an hour....  but work was done for less than estimated and promptly. 

[strawdog]

So took the truck to Bitter Creek Diesel Repair LLC Idaho Falls (was told by another shop that this was the best N14 guy around).

 

Work done -

Pull #4 injector communication loss pulled plug from ECM and troubleshoot harness, no short circuit in injector harness.

 

Load test harness to injector pass through, still no faulty wiring found.

 

Pull valve cover and found inside pass through connector was a little loose, installed new pass through to number 4 injector.

 

Checked injector 4 wiring no chafes or shorts injector wiring, checked injector 4 resistance, injector passed with .7 ohms.

 

Reassembled and started truck, no active faults, cleared inactive faults.

 

Hooked the jeep to back of truck as a small load and drove to West Yellowstone during the heat of day. Truck ran good to West Yellowstone, stoped at pullout and had lunch no problems. Started back to Rexburg, truck running good.

 

Stopped at pullout about 70 mi later for a few minutes and walked around, left truck running-

 

OhOh – engine showing same code as before -

 

ENG SID 4 5 Injector cylinder #4 Low Current

 

Engine derated, drove a bit and code inactive, a bit later (22 minutes) code returns., then goes inactive, then returns 12 minutes later.

 

Get back to Rexburg with code inactive, Problem not solved…..

 

Dave

 

[porky69]

Make sure they check/clean all of the grounds...that is what mine did, threw a bunch of parts at it (most of which didn't probably need replacing) when the computer says, multiple times, then fix the ground issue and no more problems..

[strawdog]

So pulled ECM and after a couple of dead end streets, got it sent in for testing. Result - #4 injector driver fails under high heat conditions then recovers when cooled down.

Installed replacement ECM and everything working fine so far.

That being said the ambient temps for test driving have been considerably lower than previosly so.....

Dave

[Ronbo]

Who did the testing. Other N14 owners may benefit from this info later.

[JPL]

Dave   I had a issue with the fan and took the ECM off and sent it out to Colorado and had it rebuilt. Been back on the engine for a year and a half and "knock on wood" no problems. I have a 98 610 w/n14. so I'm following  you with keen interest.   Pat

 

 

The Old Sailor

[strawdog]

15 hours ago, Ronbo said:

Who did the testing. Other N14 owners may benefit from this info later.

My intention was to get a little more drive time on the replacement ECM then post the information.

 

9 hours ago, JPL said:

Dave   I had a issue with the fan and took the ECM off and sent it out to Colorado and had it rebuilt. Been back on the engine for a year and a half and "knock on wood" no problems. I have a 98 610 w/n14. so I'm following  you with keen interest.   Pat

 

 

The Old Sailor

Sounds like the same place.....

I sent the old ECM to - DSO Industrial, LLC . Communications with them over the phone were excellent, service was fast. They tested and responded with testing results the same day they received the ECM and had the replacement shipped the next day. All programming information was sent along with the replacement.

All in all at this time I would rate them A+.

Dave

[HERO Maker]

So Dave, as you said, " Result - #4 injector driver fails under high heat conditions then recovers when cooled down. "   Is that driver inside the ECM?  And is it more of a programming issue, not hardware?