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Truck in limp mode! Help! - Printable Version

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Truck in limp mode! Help! - Silverwolf - 05-15-2021

My truck went into limp mode. Won't go over 60kmh. Computer says its a MID128 PID94 FMI1 . Says low fuel pressure. Does that mean the fuel pump packed it in? Had a similar code before but it was too much pressure, and a fuel pressure sensor repaired that. This is low pressure, could it be the same sensor or is it likely the mechanical lift pump failed. Still starts so the electric pre pump seems to work. Any help would be appreciated, Im stranded, or at least not going anywhere quick. Trying to limp to nearest city for help


RE: Truck in limp mode! Help! - Silverwolf - 05-15-2021

Sorry guess I should add its a volvo truck with a cummins isx 400 in it. Thanks


RE: Truck in limp mode! Help! - Rawze - 05-15-2021

year, make, model engine? ... truck?

is it de-mandated or not?.. and if so, by who?

some detail on background / history?


RE: Truck in limp mode! Help! - Squish099 - 05-15-2021

Oh man.. I'm scared to find out its a common rail..


RE: Truck in limp mode! Help! - Chamberpains - 05-15-2021

That's quite the generic code. But it's the one that pops up on my international 9400i when the fuel filter is restricted. Of course give us more info on the truck. But have you tried changing the fuel filters?


RE: Truck in limp mode! Help! - Silverwolf - 05-15-2021

Ok, Its a 2006 Volvo Vnl single axle. Has a 2008 Cummins ISX 400St motor, Eaton 10spd lightning shifter. Don't know what de mandated means. But its totally stock, has egr but no def. Never had an issue other than the fuel pressure sensor that set a too high fuel pressure code and limp mode. New sensor fixed that. Previous owner had a new egr valve installed at a hefty price. Doesn't get much mileage as its a personal vehicle used for personal use only. But it does have tons of mileage on it. 1.9million km. Very clean, regularly maintained as in oil changes and regular maintenance. Been very reliable.


RE: Truck in limp mode! Help! - Rawze - 05-15-2021

(05-15-2021 )Silverwolf Wrote:  Ok, Its a 2006 Volvo Vnl single axle. Has a 2008 Cummins ISX 400St motor, Eaton 10spd lightning shifter. Don't know what de mandated means. But its totally stock, has egr but no def. Never had an issue other than the fuel pressure sensor that set a too high fuel pressure code and limp mode. New sensor fixed that. Previous owner had a new egr valve installed at a hefty price. Doesn't get much mileage as its a personal vehicle used for personal use only. But it does have tons of mileage on it. 1.9million km. Very clean, regularly maintained as in oil changes and regular maintenance. Been very reliable.

Those CM870's and CM871's At 1.1 million miles without an inframe on them are a ticking time bomb... it needs an inframe at this point. One day, your going to get in it to take it somewhere and a piston is going to go through the block, complete engine destruction, and without any warning whatsoever ... and then your looking at a $40,0000 replacement engine. Those engines do not last forever and the more past a million that you drive it.. the higher this risk gets exponentially. You will swear it runs just fine and smooth and one day... BAM! out of nowhere it comes... that is what happens to ISX engines that "seem to otherwise run good" and have more than a million+ on them without an inframe.

Get that thing somewhere to have it properly inframed and go from there.


As far as the fuel pressure code(s).. you need the Insite software to troubleshoot it. What is the cummins code? and not the stupid code that comes up in the Volvo dash?.. What is the fuel pressure doing?..

* Anyone bother to replace the electric fuel pump intake screen-filter on it ... ever?

* anyone bother to replace the fuel filter a second time to see if the fuel pressure comes back?... What about the fuel water separator filter?.

* Anyone bother to replace the fuel shut-off solenoid?. It is a very common issue for those model engines for the fuel shutoff solenoid to restrict fuel.. or cause engine not to run at all after they start going bad.

* Anyone bothered to pressurize the fuel tanks to 15 psi and see if you have a fuel line or leak somewhere after an hour or so? (CAUTION: NEVER remove the fuel tank caps while the tanks are under pressure during that test).

An old vehicle like that with more than a million miles on it.. it could be a hundred different things.