[Don]

I have seen lots of cavitation erosion, but never saw or heard that it would do what happened here. If what they say is true, it is another reason to change out anti-freeze often. It is like oil changes, lots cheaper than engines…..

[Archived]

cyetter it sounds like your engine building is doing it right. I’d feel confident about that type of rebuild.

John
the Ugly Fix works by adding a resistor to the altitude sensor circuit.
It changes the signal sent back to ECM so the program thinks the
engine is operating in a high altitude. It does stop the EGR from
functioning if the “High Altitude EGR Function” is set to “off” in the
ECM program. That’s why people report very different results using the
Ugly Fix. If the “High Altitude EGR Function” is set to “on” then the
Ugly Fix doesn’t work. It depends on the factory programming. It could be set way.

Ken

[Dorel]

John,

I started with the Ugly Fix and found the ECM was programmed to have the EGR function regardless of altitude negating the Ugly Fix initially.

That was changed in the ECM. Then I had the ECM program changed to turn on the EGR at 3200 and off at 3400 RPM. Since those RPMs are not attainable the EGR no longer functions. I then plugged the path between the EGR valve and the intake manifold to stop the small amount of leakage between the exhaust and intake manifold.

The total impact of those changes brought my mileage from 5.9 to 6.2. But………..as you all know I have been tracking fuel consumption for tens of thousands of miles on my coach so after making the last change my ECM was reprogrammed to make a slight adjustment in my fuel flow which appeared to give me more power and possibly a slight improvement in mileage.

Then at about 3000 to 4000 miles prior to the end of the current phase of the testing I saw an unexplained jump in mileage. Prior to the start of the current phase in which I am evaluating the fuel additive my mileage increased to 6.4 to 6.5 MPG. It appears to have stabilized at that level. I know from logging my fuel consumption on all my coaches that there are going to be tank to tank variations, but this latest change is not based on a single refueling but might be related to the engine “cleaning” itself of the EGR related soot. That is conjecture right now but I have had feedback indicating on teardown some EGR engines have issues with soot and particulate with the #6 cylinder most affected. I have no proof.

My coach had less than 100,000 miles when I blocked the EGR. It now has about 115,000 so it took 10,000 miles or thereabouts before I saw this unexplained jump in mileage. I am comfortable is saying that if you get the EGR shut off via programming, plug the exhaust path and do nothing else you are going to see an immediate small gain in mileage and possibly a greater gain as you continue to run without the exhaust gases being pushed through the engine.

The EGR process is intended to reduce the oxides of nitrogen. It does it by lowering the internal cylinder temp of combustion. Exhaust gas introduced into the engine isn’t going to burn so to compensate for that the ECM is programmed to add more fuel and at the same time increase turbo boost from the normal 30 PSI to 50 PSI. In effect the engine is running a fuel air mixture intended to offset the negative impact of the introduction of exhaust into the cylinder. I suspect the combination of exhaust gas plus a rich mixture may prevent the engine from burning as clean and efficiently as the pre-EGR engines.

An unmeasurable, but evident impact has been on my engine oil. It remains a clean golden color far longer than it did when the EGR was functioning. One of our members did the change to my ECM. I did the blocking of the exhaust gas. I recommend the change, not because I am in effect seeing the equivalent of a 5 to 10% savings on fuel but because I think in the long run my engine is going to be much healthier.

[Archived]

Sorry fot thread creep, but Jon said:

“That was changed in the ECM. Then I had the ECM program changed to turn on the EGR at 3200 and off at 3400 RPM. “

Can this be done via the Nexiq w DD-V card, or does it have to go to DD shop?

[Dick]

No DD shop is going to do what amounts to defeating the emissions controls.

[Chris]

I probably cannot live long enough to wear out our present bus. That being said….my thought process has been that if we ever do go with a newer bus is to go no further than one of the last non EGR series 60’s. Am I just being a scaredy cat or prudent ? Geo.

[Mike]

So Jon, do I understand correctly that the ugly fix is useless unless the ECM is reprogrammed with new parameters?

[AL]

EGR, DPF and DEF systems are adding a lot of operational cost and
aggravation to the trucking industry. Motorhome owners don’t have as
many problems simply because they don’t drive as many miles and are not
under as much load. EGR, DPF and DEF systems can be correctly defeated
on Detroit and Cummins engines (not available for Volvo yet). Once these
systems are eliminated the performance, fuel mileage and reliability is
increased. Should you do it? That opens up another discussion. It’s
done in the trucking business every day.

Ken

[Dale]

So I think this brings us back to adding additives to each tank of fuel. Some of the better products do advertise reducing soot, increase in performance do to more punch when the big bang happens.

This would keep everything in place on EGR system and maybe better performance.

[Chris]

I don’t think any additive will eliminate the abrasive particles
contained in diesel exhaust. Some percentage of the exhaust containing those particles will always be returned to the engine if the EGR
system is functioning. I think if there were a cost effective addivitive available that would eliminate the EGR problem truck owners would be using it instead of paying to have their ECM reprogramed.

Ken

[Darrell]

Al, I know one of our advertisers is vbery excited about additives, but with almost 3000 miles using additives so far I have no measurable improvement in mileage.

I never established a baseline measurement for performance so I cannot say that has increased due ot the use of the additive. My most significan improvemant as stated above is related to deleting the EGR function. The stuff is still on the engine, but it is not functioning because it will not come on until my engine is turning 3200 RPM.

Roger, If your ECM is programmed as mine was to not turn off the EGR above a certain altitude the Ugly Fix will not work. I do not know how yours is programmed. They are supposed to not allow the EGR to function above 11,000 or 12,000 feet, but that was not how mine was programmed

[Archived]

I don’t know what is different but my ugly fix works, went from 5.9- 7 mpg that is reading from the ddec reader might be the jake brake ecm over the brake retarder ecm, I can say but it works, no more black smoke. I did not reprogram the ecm, also the oil stays cleaner longer. Darrell

[Rudy]

Jon,

Is there an easy way to tell if the ugly fix is working when plugged in? When I get my coach back I want to stop the EGR function to keep as much crap out of the engine and oil as possible.

Chris

[Dale]

Aight, Jon’s oil is golden, mine looks black to me. I see black smoke when it drops a gear, only for a second. Are they related? Mine is pre-EGR.

[Richard]

Bonz,

My oil is black after just a few miles, it’s normal.