Check engine code P026A Charge air cooler

I have thrown this code a few times already and have not found much info on it for our cars. If anyone has an idea on why it gets tripped or what I need to fix it please let me know.

000618 - Charge Air Cooler
P026A - 000 - Efficiency Below Threshold - MIL ON

This only has happened when when I run my idi cold weather front.

Happened to me on the Passat with cold weather front on. Removed it and cleared the code and all okay. Only the lower needs to be removed.

Lightflyer1 said:

Happened to me on the Passat with cold weather front on. Removed it and cleared the code and all okay. Only the lower needs to be removed.

Click to expand...

Yep, same here. I only saw this when the temps were above freezing (~35F+) and heavy driving (lot of stop & go, low velocity airflow)

Mine was highway on cruise at 65 mph. I just don't use the lower any more after reading here some.

I've had the full IDparts grill block on for about 2 weeks now. Today it was about 35*F with lots of moisture. Driving along for about an hour and the CEL came on solid. Thought she went into limp mode for about 10 seconds. Then ran good. Responsive to the throttle with normal boost and power. As the CEL was not flashing continued to my destination. The DTC was charge air temp high. Before the CEL came on I also noticed my charging voltage was lower than normal. About 13.4VDC showing on my Scangauge. So thought engine compartment heat was lowering my charging voltage along with the charge air temp high and so removed lower grill block. I cleared the CEL and drove the rest of the day without it coming back on. The charging voltage on my SGII was back up to 14.2-14.5VDC with the block off.

The above is what I posted in another thread. If I'd paid attention to what my Scangauge was telling me I would have removed the lower block and never gotten the CEL. With too high an ambient temperature the IC will run too hot and throw a DTC. I now also have an XGauge on my SGII for Intercooler Charge Air Temperature.(ICA*F)

Good that you mentioned the grill block in your post.

I've had my lower grill block on since temps have been below 42°F. That's been a solid month or so now. I only put the top cover on when temps are below 20°F.

I'm thinking that cutting holes in the bottom cover may eliminate the intake temp too high.

I have a question for you guys having this problem... Do you have the tsb intercooler installed or the one straight from the factory?

ATR said:

I've had my lower grill block on since temps have been below 42°F. That's been a solid month or so now. I only put the top cover on when temps are below 20°F.

I'm thinking that cutting holes in the bottom cover may eliminate the intake temp too high.

I have a question for you guys having this problem... Do you have the tsb intercooler installed or the one straight from the factory?

Click to expand...

My intercooler is factory.

scow1 said:

I have thrown this code a few times already and have not found much info on it for our cars. If anyone has an idea on why it gets tripped or what I need to fix it please let me know.

000618 - Charge Air Cooler
P026A - 000 - Efficiency Below Threshold - MIL ON

This only has happened when when I run my idi cold weather front.

Click to expand...

You blocked the intercooler with a cover and now it's throwing codes for the intercooler not performing to specification. Remove the upper cover and you should be okay.

I had the same thing happen over the last few days.. Didn't notice this thread. Posted one of my own a few above this. I am pulling the uppers off of both my vehicles. ID parts should sell the separately. I will probably not put the uppers back on. Funny thing is that mine only started throwing CELs when temps got down into the teens. Have been running uppers and lowers since before Christmas even in 40 degree temps with no issues. So much for my $200.00 investment! (2 sets).

Generally the uppers should only be used below 25*f (my experience). My lower is on when it's below 40*f. I haven't had codes or issues, and I do have a TSB kit on my car. This is a really puzzling phenomenon... any chance the people who are getting codes are drawing intake air directly from the engine bay (i.e. bypassing the intake snorkel) Check that your intake snorkel isn't removed, as the dealer removed it as a 'bandaid' if your car presented IC condensation/icing issues. It attempts to increase intake air temps by drawing warm engine bay air in, instead of colder air from the intake slits right at the tip of the hood.

Just a random thought that popped through my head.