2011 RC Colorado 3L TD Check Engine Light

Post Reply
KA74
Posts: 9
Joined: Mon Oct 11, 2021 11:33 pm

2011 RC Colorado 3L TD Check Engine Light

Post by KA74 »

My 2011 RC Colorado 3L TD check engine light has just come on, no obvious issues when driving.

Starting the process of getting mechanic to look at it. I assume they will put a computer on it to look for fault codes.

Are there any common reasons for the check engine light to come on?
mydmax
Posts: 1856
Joined: Sat Oct 12, 2013 8:36 pm

Re: 2011 RC Colorado 3L TD Check Engine Light

Post by mydmax »

KA74
There are many reasons why a check light will happen, the issue is, which anomaly/fault is causing it. A mechanic may not have a "computer" as such, but will most likely have a code reader to read codes, if any are registered. For the price of a code reader in todays world, around $!00 for a decent one, they are worth having and carrying with you. If you do a google search for Isuzu/GM for 4jj1 fault codes and print them out, then you can read/reference the code, ID it with the list and see the area of fault. It may be a simple fix.

If the EGR valve is choked up and restricting EGR flow into the inlet manifold, that flow imbalance will register a code. Even so, it f is that, ONLY cleaning the EGR valve, will restore it.
The issue could be wiring, a loose plug to some component, or sensor somewhere. The code reader narrows it down. so items can be checked. This is exactly what the mechanic will also do. With a code reader you can check and possibly rectify and only see mechanic is need be.

If your vehicle has lost power at same time, check the little hose on the turbo boost chamber, mine dropped off and NO BOOST and limp mode. Secured it back on the chamber, erased code with code reader and drove on.
Hope you find it.
KA74
Posts: 9
Joined: Mon Oct 11, 2021 11:33 pm

Re: 2011 RC Colorado 3L TD Check Engine Light

Post by KA74 »

Thanks Mydmax,

Yep, the EGR came up as a fault on the code reader. But it has also gone away after the car cooled down (but likely will come back).

Mechanic said leave it till it comes on again, deal with it then.

Sounds like it needs to be cleaned.

Assume these are cleanable with carby cleaner or similar. Never had a diesel vehicle with EGR before. Haven't gone through the service manual yet, still at work.

Another project....
mydmax
Posts: 1856
Joined: Sat Oct 12, 2013 8:36 pm

Re: 2011 RC Colorado 3L TD Check Engine Light

Post by mydmax »

KA 74
The EGR is controlled by a stepper motor which has the wires running to it. It may be heat affected and becomes faulty when hot and unable to operate and control the EGR flows as normal, ie, stops in one place instead of regulating as the ECU wants to see/detect. The other issue is it may simply be dirty/gummed up with carbon and sticks and the stepper control is ok. Check the wiring plug for CLEAN first. If handy you can remove the EGR valve and clean it. If no aluminium parts, oven cleaner may do it ok as it dissolves the carbon.
Do you have a Catch Can fitted to minimise the amount of oil fumes laden blowby gas? That oily blowby which allows the hot EGR flow to cook and bind up the EGR and eventually fills most of the inlet manifold with oily goo and restricts air intake to cylinders. A good thing to have.
Post Reply