Isx doc fault code

First you have to fix exhaust leak. You can buy and replace sensors by yourself. How many miles on the truck?

 

If you can tell me what the codes are, I can help you better, but my guess is you should fix any of your exhaust leaks, and regen the truck to see if it clears up. What engine do you have in your truck?

 

An exhaust leak will cause a fault code for the DOC face not coming up to the proper temperature for a regen. First remove your truck from that incompetent rip off shop. Next fix the leak and have a shop with the proper equipment clear the code causing the warn engine light since that is one that won't clear itself. Check for any other codes and have the shop do a forced regen. Drive to see if it sets any other codes.

What year and make truck is it and how many miles? If its an International you can push the cruise on and resume buttons at the same time to display SPN and FMI numbers that can be converted to fault codes.

 

DOC, DPF and doser injector need cleaning every year or two. If you have never had them off and cleaned, this is the one of the first steps. I agree, DOC replacement is a last resort.

 

Is there a safe way to clean sensors on the back of the DPF stack?? Thanks

 

The temperature sensors do not need cleaning. They are just a metal probe. The DPF differential pressure sensor and tubes can get carbon plugged. You just remove them and blow through them with shop air and make sure the hole is clear at the DPF too. This would also be a good time to disconnect the connectors at the sensors and make sure they are clean inside with no green.

 

Correct me if I am wrong but no chemicals correct?

I'm have to clean my exhaust inlet pressure sensor and I'll probably to the IMAP? sensor also.

The doser is $325. Not exactly breaking the bank if you do it yourself but you do have to
drain the coolant.

 

Cleaner sprays should not be used. The only thing I highly recommend is to apply lots and lots of anti-seize to the threads and in between the fitting and sensor or tube so the fitting spins out nice every time. If not, you will strip out the threads and/or ruin your sensor or tube. The carbon is just powdery anyway and should come right out with a small pick or screwdriver and shop air. If it is hard packed then that means it is mixing with excessive coolant or oil. I forget which engine we are talking about here, on MF engines, and I think some Cummins too, once the solid fuel line to the doser is removed, you can unbolt the injector with the coolant lines still attached. They are flexible and you can move it up out of the way enough to clean any carbon build up on the tip. A soft brass or nylon bristle brush or even just a shop rag does the trick. Always make sure you stick your finger down the bore hole in the pipe to make sure it is clear too. Carbon packing can be really hard here sometimes and you may need a small chisel. Sometimes all the carbon sticks to the pipe and not the injector. Make sure to use a new gasket. On Cummins with solid coolant lines, you can disconnect the turbo outlet pipe and clean the injector tip from inside the pipe by using a mirror. Only takes a few minutes.

 

Is the code something like "DOC face plugged - Root cause not known"?
If it's a Cummins or PACCAR with the Holset aftertreatment system, I would at least separate the DOC from the DPF, blow it out with compressed air, and inspect it to ensure that the DOC isn't cracked. You'll have to replace some gaskets, but it's a lot cheaper than replacing the DOC if it doesn't need replacing.
Is there, by chance, a corresponding code which reads something like "SCR Catalyst Conversion Efficiency - Data Valid But Below Normal Operating Range - (Least/Moderate/Most) Severe Level?