Pacar MX Engine fuel mileage

Have you done the E053 and E056 updates for that engine?

 

I'll check with the shop as soon as I'm there but according the comouter there's no new updates waiting. Have always been one of the first to update...

Thanks

 

All updates have been done.

Mechanic changed the fuel lift pump which had the result that fuel pressure became steady at all rpms. No lights came on while testdriving, he was convinced to have solved the problem.

But problem is back. Have to hook on all the test equipment again and see what fuel pressure looks like now...

 

Problem solved..!!

Problem was the fuel pressure regulator. Sounds logical when you think about it.

Fuel pressure seemed okay but after running the engine for a while at 1300 rpm pressure started bouncing around getting below 40 psi evry now and then. When running steady on the highway on cruise at 1300 rpm check engine light came on because of the low pressure. There's no real explanation why it didn't happen when driving loaded. perhaps engine needed to work more then causing different pressure. When loaded and engine had to work hard passing 1300 rpm fuel pressure became so low that red light got activated. It remains strange however that the red light never showed up in history of codes...

But everything should be fine now, leaving Sunday early for Toronto. Hope fuel mileage and performance are still in the new mode. Two weeks ago suddenly everything started working better. Fuel mileage went up 10 - 20 percent, I had more boost, more power...

 

I hope all is good now for you.

Keep us updated how this story evolves.

Who knows,you mind end up loving your MX.

 

Hope it solves the problem. I understand you like this shop ,but they never looked at the regulator before ? What's up with that.

 

Please keep us updated as to how she performs and economy wise.

 

First fuel pressure seemed okay and then you start thinking on sensors not working well. When they hooked it on to the gauges the service desk advised to change the fuel pump. That seemed to have solved the problem but did not...

I'm not a very technical guy but it seems to me that when you have fuel pressure not working well, you first check the pressure regulator.

I think the red light coming on wihout a code was some sort of a disturbing factor. It wasn't clear whether they dealt with one or two problems...

 

Driving a 2011 T700
I'm not sure exactly how the truck is speced but very happy with fuel mileage. Just seems to keep getting better Truck has 120000 miles now. Always over 7 mpg loaded
pulled out of LA going to Denver at 69000 and still avged 7.3 going across 70. Came out of Fort Collins at 79820 and avg 7.6 going to Waco. Auburndale Fla to Tomah Wi 7.4 @78600
Paw Paw Mich to Breese Il 8.8 but only 10000 in the box Breese to KC was down to 8.2 a lil hillier but a head wind of 15.
I am sure as we see more weather my numbers will go down a bit been perfect driving weather for months

 

I was startin to loose faith but always have said that the engine could perform much better then it did, for performance and fuel mileage. In fact it was me trying to convince Paccar engineers that 5.5 mpg is not good...

It's still different worlds, Europe and Canada/US. They think big here, the MX is a small engine, you can't get that out of there heads. I think the European way, leaning towards smaller engines. When I tell them IVECO and Renault do lang haul 90,000 gross weight with 11 liter engines up to 475 hp they think I make it up. When you tell International mechanics that the 13 liter is the big engine in Europe and they mostly use the 11 liter because it gives better fuel mileage it's the same story... When you do 100,000 gross you need a big engine, an ISX 15 and not a Paccar MX...

I hope I'm able now to prove them wrong. Last trips I did over 6 mpg and could almost keep up with the big engine guys.

Hope mr Scania man isn't right and my engine will not blow up or otherwise break down... So far not using oil, no other major problems.