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Can a failed or failing MAP sensor cause my truck to be very sluggish down low and continuously the P0234 code? 

 

I once upon a time had an edge ez but it’s gone now. The boost elbow that came with it is still installed though. I have a fass lift pump and a FP gauge. Otherwise all stock. Truck feels like a total pig off the line and doesn’t feel like it starts making any power until 1800 rpm or so. Also has trouble holding highway speed in OD on any hills even empty. 

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    Mopar1973Man

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  • Author
27 minutes ago, Me78569 said:

5 to 4.5v steady

Got 4.94v key on/engine off and engine running 

  • Author
1 hour ago, Me78569 said:

Map is toast then.  

Thank you. Guess I’m heading to the parts store for a MAP and a wastegate actuator. It never seems to end. 

  • Author
34 minutes ago, Mopar1973Man said:

Even with the boost hose and bolt missing out of the manifold didn't change boost much maybe lost 5 PSI.20190529_112624.jpg20190529_112612.jpg

So what your saying is a small leak isn’t going to make much difference? The leak in the wastegate actuator bleeds off pressure almost as fast as my compressor can get air in. I assume it’s not supposed to do that? It’s the only leak left as far as I can tell. 

 

Also the boost elbow I have is from an edge ez and it just has a hole right in the side that leaks air out is that supposed to be there? I looked through old parts but couldn’t find the original elbow. 

Edited by skyhigh4by

A small leak will make a small difference. The bigger the leak the bigger the difference. While your air compresor can compress are 150 psi or whatever yours is capable of, it most likely cannot produce the volume of air that the turbo can. My little compressor will get to150 psi but only produces maybe 3 cfm at 90 psi, could be less. The turbo is capable of many times the cfm of my compressor. A quick, and I mean quick google check said the HX35 is capable of 600 cfm. Others would know better than I. I hope can see what I am saying.

 

The boost elbow that came with my Comp has an adjustment screw in it. It lets pressure of of the actuator so you can build more boost than stock. If yours is missing the screw it is just letting the waste stay closed longer. Do you have a boost gauge? Are you still running the EZ?

 

Dont get me wrong if you have boost leaks, fix them. Your truck will be happier. But for now a MAP sensor is what you need. Fix that then take care of the other stuff.

Just my :2cents: worth.

  • Author

Okay thanks. I get what your trying to say about the compressor. I’ll start with the map sensor and go from there. 

 

No the edge is no longer on the truck. It started working intermittently and I ended up throwing it in the trash. With what I know now it could have likely been the map sensor that was the problem and not the edge. I wanted to get a quad anyways but not until I’ve got the truck running right in stock form. 

 

No boost gauge and I would bet the adjustment screw is missing from the elbow. It looks like there could have been threads in there but they’re all buggered up.

 

I cant figure out whether or not the wastegate actuator should leak past the diaphragm or not. I put 25psi into the boost hose and the air just leaks through and out past the rod and the rod doesn’t move. I don’t think that’s supposed to happen?? 

Edited by skyhigh4by

  • Owner
13 minutes ago, skyhigh4by said:

I put 25psi into the boost hose and the air just leaks through and out past the rod and the rod doesn’t move. I don’t think that’s supposed to happen?? 

 

No. Sounds like the wastegate motor is shot.

If you took the EZ off thats why you got the 234 code. The EZ did boost fooling so you can build more pressure. With out it the ECM will defuel the engine once you pass 20 or so psi of boost. I would replace the actuator too. But do the MAP and see how that does and then tackle you other issues.