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J.R., Technician
Category: Heavy Equipment
Satisfied Customers: 7445
Experience:  13 years as warranty technician for Detroit Diesel
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Mirage: 60 series detroit motor..knocking noise..sensors..vibration

Customer Question

codes shooting 78 and 55 on 60 series detroit motor, getting hard knocking noise in motor, but what could cause poor fuel milage with no internal sensors to cause this, also alot of vibration
Submitted: 8 years ago.
Category: Heavy Equipment
Expert:  J.R. replied 8 years ago.

Section 55.3
Troubleshooting Flash Code 55

The following procedure will troubleshoot Flash Code 55.?

Section 55.3.1
Check J1939 Data Link

Perform the following steps to check for J1939 data link fault.?

Is this a J1939 transmission/engine application?

If yes, contact Detroit Diesel Technical Service.

If no, use programming station and go to "update customer calibration" and select transmission to manual, or correct transmission. Save changes. Refer to "55.3.3 Verify Repairs" .

Section 55.3.2
ECU Code Check

Perform the following steps if code 216/14, missing other ECU displays. This indicates DDEC ECM has lost its connection with other ECU devices and a lost or shorted J1939 data link. ?

If code 86/14 displays also, there is a fault with the smart cruise. Contact OEM for instructions.

If code 84/12 displays, the fault is with the programming of the ECM, or a short exists to the J1939 data link. Contact OEM for VSS (Vehicle Speed Sensor) troubleshooting.

Section 55.3.3
Verify Repairs

Perform the following steps to verify repairs.?

Start engine.

Plug in DDR.

Read codes.

If active codes 216/14 or 231/12 are not logged, troubleshooting is complete.

If active codes 216/14 or 231/12 are logged, contact Detroit Diesel Technical Service. Check DDR software level. Update DDR software if current level is 1.2.



Section 78.3
Troubleshooting Flash Code 78

For troubleshooting Flash Code 78, follow these procedures:?

For intermittent fault code 86/14, ensure ECM programming is updated to level 32.00 or higher.

If code 86/14 is logged with 216/14, for troubleshooting refer to "55 Flash Code 55 - J1939 Data Link Fault" .


Customer: replied 8 years ago.
what about knocking and vibration and i turn motor off and shuts off hard
Expert:  Diesel Pro replied 8 years ago.



A hard engine knock and vibration is sometimes caused by too much fuel from injector or internal engine damage. Check your oil and smell it, to check for fuel in the oil (bad injector) or check for water in oil (internal engine damage). If every thing is good, have your technician check your engine computer and harness for defects since you have a code 55.


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Diesel Pro

Expert:  J.R. replied 8 years ago.
The knocking etc can be caused by the ecm not performcorrectly if it is not sending the correct readings to injectors etc. I would suggest that you take it in to a dealer to have the ecm checked out.
Customer: replied 8 years ago.
i did 2 o.a.'s waiting on one to come back 1st one said had coolant in it, they said level in it was fine, not a concern
Expert:  J.R. replied 8 years ago.
Who did you have do the oil analysis? Do you remember what the level was at? You may have some cavitation to the injector tubes.
Customer: replied 8 years ago.
.03% coolant in oil and fl of utah
Expert:  Diesel Pro replied 8 years ago.



I forgot to mention, did you have a cylinder cut out test done? This would pin point your bad cylinder if any? some water in the oil would be a concern. I would have engine pressure checked to verify.


Let me know if this info helped. Thanks.


Diesel Pro

Expert:  J.R. replied 8 years ago.
The .03% is nothing to worry about. Levels that are that low could be caused by condensation. I would take in and have it checked out by your local f/l or detroit diesel dealer and they will get you taken care of.