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cumminsdr
cumminsdr, Mechanic
Category: Medium and Heavy Trucks
Satisfied Customers: 3541
Experience:  All types of Cummins applications
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Having trouble with a ISL running rough. no codes

Customer Question

Having trouble with a ISL running rough . no codes
Submitted: 1 year ago.
Category: Medium and Heavy Trucks
Expert:  spankyjr1 replied 1 year ago.
Hi, my name is ***** ***** you for your question.
Sorry for delay.
How many miles on engine?
So now it runs but runs real rough?
Has fuel pressure been verified?
Does it start up now without either?
Let me know
Customer: replied 1 year ago.
Trash truck unknown mileage. Good fuel pressure. And no either needed as stated in my question.
Customer: replied 1 year ago.
Also why us insite not seeing engine rpm ,
Expert:  spankyjr1 replied 1 year ago.
You said it ran fine for a month after injector replacement but did not say if ether was used or not to start.I needed to be sure.
Since it was running fine after first injector repair your issue showed up after second injector repair so I think you got a bad injector!
I have got bad ones out of the box new or rebuilt it does happen more than you think.
Since you are not getting codes it's not a electrical issue and fuel pressure is good it only leaves bad injector.
Also injectors should be changed as a set if mileage is unknown or over 500K,since this is a garbage truck it would be by hours on engine.
Anyway when you replace just one or two injectors it throws of the balance of engine and the ecm is trying to compensate for the injectors being different in the amount of fuel being delivered.
If it was me I would replace the one that caused this (#3) and the rest of the old ones.
If timing was off it would throw a code.
Thanks
Customer: replied 1 year ago.
At $800 an injector the customer won't pay for that. And Cummins won't warranty the injector after installation. And again why will insite not see engine rpm so I can run a cut out test or cylinder contribution
Expert:  spankyjr1 replied 1 year ago.
You said Insite did see RPM, Quote:But i can see rpm in insite.
I don't have time for this now so I'm going to opt out and put question back on open board,please don't reply to me or question will come off open board and no one else can see it.
I don't know how long it will take for another expert to reply
Good luck
Expert:  cumminsdr replied 1 year ago.

Hi so what repairs have been done so far on this unit?

Expert:  cumminsdr replied 1 year ago.

What is the current ecm calibration shown in Insite?

Customer: replied 1 year ago.
Number three injector replaced , ohm's were very high. After replacement code for that cylinder was clear. But unit still running rough but not like a dead cylinder . swapped # ***** and #3 injector problem stayed in number three . had to change timing sensor so insite would run cylinder cut out and contribution. Going to do a leak down test and compressions test to see if there is internal damage. Also ECM is clear no codes. Don't know the calibration unit is 2 hrs away
Expert:  cumminsdr replied 1 year ago.
Do you have the engine serial number?
Customer: replied 1 year ago.
Unit is two hours away , going up there in the morning. I can get it then. And the calibration
Expert:  cumminsdr replied 1 year ago.

Do you need more assistance? Please don't forget to rate my service.

Expert:  cumminsdr replied 1 year ago.

Hi just following up. Do you need more assistance? Please don't forget to rate my service. Thank you for allowing Just Answer to assist

Expert:  cumminsdr replied 1 year ago.

HI do you need more assistance? Please don't forget to rate my service