After slowly picking off some codes I've been getting, I'm finally down to just this one - P0234 (turbo overboost).

I've done some searching around and it looks like I might need a MAP sensor? I'm not familiar with exactly where this is but it looks like a plug and play sensor. Do you think this is it or are there other things I should check first?

Truck seems to be running fine - no check engine light, I only pull the code when using the key on/off trick. Truck is stock/no performance mods (I did recently get rid of my AFE intake for a stock setup).

Thanks

 

I have the same code, same situation... truck [I]seems[I] to run ok, no check engine lights, etc. but I'd love to know what causes this and what I can do to fix it.

 

Sticky or stuck open wastegate. If it were the sensor, it would cause limp mode.

 

What's involved in fixing the wastegate?

 

I'd love to know this too. How freely should it move? By hand or with pliers? Best way to test operations?

If it is throwing a P0234 code, does this mean that until the problem is fixed, boost is limited? Chime in guys!

 

Try stuck CLOSED for overboost code --- if it was open you would have a big boost leak and the truck would be smoking black.

 

Guy's try checking the map sensor connections and then clear the code to see if it returns.

If you have larger injectors without a programer or a boost fooler you can cause overboost and get this code.

Normally their is a heavy spring in the wasegate actuator housing that holds it shut until it is overcome by boost pressure that will then push it open as needed. It should move freely and not bind but could be stuck if it has not opened before or in a long time.

 

Other dtc’s
wastegate stuck
turbocharger and/or wastegate damage
wastegate
turbocharger
wastegate control valve

 

OK i have a bully Dog PMT and a boost fooler i just purchased cause i have been throwing over boost codes for years, so now bf is installed so no more codes but only making 27 Lbs of boost floored in extreme mode, I can not seem to move the actuator by hand does this mean its stuck ? and how to make it unstuck ? also if it does break free should it move like an inch?

 

genosgarage.com has a manifold boost bolt for about $5, get a oil pressure gauge instillation kit for $10 and a glycerin filled 60 psi full scale gauge from ww granger for $18 and see what is happening. I was having a problem and built my own bolt in about 5 minutes.

 

I could be wrong but because the Boostfooler is fibbing to the ecm my bullydog is fibbing to me after all it is plugged into the computer. I am going to have to put actuall gauges in to see whats going on thanks for the response those pics will help me alot.