Nonstop codes in limp mode, codes P0122, P0222 andP0443

FNNLT

MEMBER
2008 CHEVROLET TAHOE
5.3L
V8
4WD
AUTOMATIC
419,000 MILES

The car is stuck in what I think limp mode.

First round: tried to switch the engine on but it didn’t, and suddenly the following messages appeared:
Engine is hot
A/C turned off
Engine power reduced
When scanned, these codes found at once:
P0122 - P0222 - P0443

fix attempts:
cleaned TB;
inspected wiring of TB, Purge valve, ECU, Grounds, Accelerator pedal.
Disconnected batt for an hour, removed ECM fuse, inspected relays and fans connectors...

Results so far:
Nil, still limp mode for around 18 hours.

1 Reply

KASEKENNY

MECHANIC
18,907 POSTS

These issues could be related but the first two are for the throttle position and the last is for the EVAP system. So that means we need to start with the throttle codes and if that fixes all three then that is great.

If not, we can move onto that one.

Basically, these could be related if the 5-volt reference circuit, but we need to confirm this first by following the testing below.

https://www.2carpros.com/articles/how-to-check-wiring

I suspect we have a wiring issue or a PCM issue since you have codes for both TP 1 and 2 so let's start with this testing and see what turns up.

Let me know if you have questions on this.

Thanks

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