Check engine = no overdrive?

I had a check engine light come on and the transmission has stopped shifting into 5th
( overdrive) now.
Can these 2 issues be related or just a coincidence?

Thanks

 

yes, they could be related.
Get the truck scanned for codes, then report back.
When can better help you then

 

OK, Interesting.
I actually put a scanner in it tonight, and the code P0037 came up. so faulty 02 sensor most likely.

If that is really causing the transmission to go into some type of "safe mode" that is very interesting. I have never experienced such in any vehicle before that has had check light on.

 

‘Limp Mode’

very unlikely to be related to your issue. I had a knock sensor code and it did the same thing.

 

I should add: not only will your truck not go to 5th gear, it will also use more fuel and slow the timing of all your gear changes…. As you have noticed no doubt

 

All because of bad 02 sensor!?

 

Is it possible it won't go into OD if it's constantly in open loop fuel control?

 

I wouldn't expect an O2 heater to cause any sort of failsafe (limp) mode.

What year is your truck?

Are you sure that's the only code and you didn't misread the code?

 

It is a 2008.
It is not in limp mode. It just stopped shift into overdrive after the check engine light came on. And hasn't fixed itself. So I naturally start to assume these 2 issues must be related.

And when someone stated here prior the timing of all gear changes would become slower as well. Was he referring to 02 sensor issue or some type of issue with knock sensor ( detonation caused by bad fuel? )

 

No I was just referring to the information I have read about limp mode or a fail safe mode. I recall it’s a protection against pre-detonation.