0

Score

Avatar
Daniel Joy
1

Asked

2010 ISX has vibration under power is worse at 1250 to1350 rpm.

History

Vibration is much worse when loaded and pulling harder

don't think it's fuel filter as it doesn't change after a service. one mechanic thinks it's normal . Not happy with that thought. thanks for your input guys.

Daniel Joy,

Add Comment Cancel

Post Answer

1

Score

Avatar
Allan Wilson
185

Answered

PermalinkHistory

One possibility is fuel starvation. My truck will do that when the fuel filter starts to clog up.

Add Comment Cancel

0

Score

Avatar
Anthony Vine
1

Answered

PermalinkHistory

I have the same problem, but my vibration starts at 1150rpm. If you back off the accelerator to less than 50%, the vibration goes away. Does sound like a starvation problem, but have a Cummins shop run diagnostics that center on the injectors, and check the connections.

Changed the low-pressure filter, but found out it did little to change the vibration.

Add Comment Cancel

0

Score

Avatar
dynamo440
43

Answered

PermalinkHistory

I have been living with a similar problem for two years with my 06 ISX450.

On my truck the “choppy” running condition is very noticeable above 1000 RPM but feels worse between 1200-1300 RPM. I feel it when the truck is parked or anytime the throttle is applied while driving down the road. If you back off the pedal it goes away. It is also worse with heavier loads or in hard pulls.

I have taken the truck to Cummins many times to fix this and It always turns out to be a bad metering or timing actuator. These actuators are paired together on each side of the shut off solenoid located on the IFSM (integrated fuel system module) which is bolted to the driver's side of the engine where the fuel filter screws on. There are two metering and two timing actuators in total. These electronically controlled actuators allow the ECM to advance timing and fuel to the injectors. The front pair controls the front injectors (#1,#2,#3) and the rear pair (#4,#5,#6.)

Here’s the bad part: The dealer will replace the bad actuator and the truck will run smooth for a month or two then it will start running bad again. After the 4th stay in the shop for the same problem I decided to invest in the Cummins software (Insite) so I could diagnose the problem myself and bypass the dealer. I am convinced now that the bad actuator is not the problem but the symptom of something else. I have replaced the ECM and soon will replace the wiring harness because I have gone through 11 metering actuators and 6 timing actuators to date.

I’m not saying that this is what is wrong with your truck but I think mine might not be the only one doing this. Unfortunately If this turns out to be the same problem for you, I don’t have a fix yet and neither does Cummins. I have been in contact with the senior customer advocate with Cummins corp. and they have had several experts look at my truck and they can’t figure it out either. I was also told that they will not invest a lot of time on this problem because this is an obsolete system as the new 2012+ ISXs have abandoned the IFSM for a common rail system.

Here are some additional things thoughts:

These “NEW” actuators are actually re-manufactured by Cummins. They call it a “recon”

Problem gets worse in warmer temps(75F+)

Actuators usually go bad in pairs (metering+timing on same bank)

Actuators never fail outright so no codes are ever generated.

4 new(recon) actuators have leaked fuel from the connector when new.

sounds exactly what mine is doing. I have the PDI delete kit. Cummins is giving me a hard time about diagnosing anything, saying take it to the shop that installed the delete kit. Of course he doesn't have the equipment to diagnose or test most parts. PDI went through the ECM everything is as should be. I'm getting 7.6mpg. Happy with that, the vibration/stuttering is irratating more than anything. You know it's not normal, and is it symptom leading to something more serious.

Daniel Joy,

Add Comment Cancel

0

Score

Avatar
Travis McCauley
1

Answered

PermalinkHistory

Unplug ur fuel temp sensor check engine light comes on but vibration goes away tried changing sensor didn't help nobody can tell me wats wrong

Add Comment Cancel

0

Score

Avatar
Your
1

Answered

PermalinkHistory

I also have the PDI delete !%% well with the same problem. Unpluged the

fuel temp sensor and smoothed the engine right out. Runs much better. Check engine light is on but doesnt seem to be derating engine.

Add Comment Cancel

Add Your Answer

View Statistics:

Today: 9

This Week: 24

This Month: 138

All Time: 3,157