Just replaced vp44 because I install quadzilla adrenaline and 2 days later I started truck and no power. Truck wouldn't make more than 5 psi boost. Everyone said it was vp44. But now truck is still the same. I was making 25psi without tuner. I have newer map sensor and I reset apps. Please help...... I am well versed with a voltage meter.

Boost leaks in the intake system or a stuck open waste gate maybe. 

36 minutes ago, dripley said:

Boost leaks in the intake system or a stuck open waste gate maybe. 

Thought that also. Checked that before I bought new vp44. The turbo is not spooling . I will post codes tomorrow after I get them. I feel like the quadzilla boost fooler isn't working. Or maybe map sensor went bad again. 

How about some more info on your truck. Go to your profile and fill in your signature with your truck info. It will appear on every post you make and help with diagnosing issues. By all means if you have codes post them. The only thing the trubo needs to spool is for the engine to burn fuel and plenty of air.  

Check for the error codes and list the code numbers here and we'll get you lined out with diagnostic stuff. How about fuel pressure is the fuel pressure 14-20 PSI from idle to WOT?

17 minutes ago, Mopar1973Man said:

Check for the error codes and list the code numbers here and we'll get you lined out with diagnostic stuff. How about fuel pressure is the fuel pressure 14-20 PSI from idle to WOT?

I am sitting at 19 idle and wot 17. I am gonna go buy a scan tool now. Brb

@Raffron do you have an exhaust brake?

1 hour ago, trreed said:

@Raffron do you have an exhaust brake?

I do. But it is not hooked up.

 

2 hours ago, Mopar1973Man said:

Check for the error codes and list the code numbers here and we'll get you lined out with diagnostic stuff. How about fuel pressure is the fuel pressure 14-20 PSI from idle to WOT?

I am sitting at 19 idle and wot 17. I am gonna go buy a scan tool now. Brb

Just now, Raffron said:

I do. But it is not hooked up.

 

I am sitting at 19 idle and wot 17. I am gonna go buy a scan tool now. Brb

I read codes. P0237. That's it.  Will not erase.

I've seen it where the buttefly valve in there is either closed or partially closed, and causes this exact scenario.

But that map sensor code could point to a false reading and that's messing with the fueling table. 

Edited April 7, 20187 yr by trreed

Is your acceleration quite slow like 50% power or less?  I have been struggling with a similar issue, though not constant but the same 237 code.

When I did my vp and was not going to retap the pump I coiled up the wires (including the ground wire for the edge comp) truck would run and drive, but it would fall on its face at 3-5 psi. I don’t know the wiring of the quadzilla but I felt like an idiot when I figured it out.

 

good luck hope you find it soon

Edited April 7, 20187 yr by portlandareae28
Spelling error

1 hour ago, portlandareae28 said:

When I did my vp and was not going to retap the pump I coiled up the wires (including the ground wire for the edge comp) truck would run and drive, but it would fall on its face at 3-5 psi. I don’t know the wiring of the quadzilla but I felt like an idiot when I figured it out.

 

good luck hope you find it soon

I am not retapping this pump.. but I am gonna Check wiring again. I do the that the quadzilla is on at least. Thank you for the advice.

It drove me crazy, everything was right , “should be fine with the edge off” but even with it turned off it would not get out of its own way.

Yay! I got it figured out. The map sensor was bench testing at 5v in and 5 v out. Toast! New one in and boost back. Now I just need a good tune for it. Thank you everyone for all the time and input. Now where is that button to donate?

Odd thought... What if the ground line of the MAP sensor and APPS sensor are floating some voltage? It would impact your range of throttle. This might throw off the MAP and APPS signal as well. Remember one thing sensor grounds are NOT body grounds! This brings me back to the passenger battery terminals and good ground over there. 

 

I know the APPS sensor is share between the PCM and ECM computers. ECM for the fueling but the PCM for automatic shift functions. 

 

If you are feeling really bold...

 

Edited April 8, 20187 yr by Mopar1973Man

I know in my instance I believe the problem lies in the sensor ground splice buried in the engine wiring harness, though it could be both. I was able to stop the 237 code and then eventually stop the low power issue completely, though not permanently, by manipulating that part of the engine wiring harness mostly by just having my hands in there. But this last time I did it purposely and it all stopped. The truck runs fine again. I am going to do the main computer grounds tomorrow weather permitting. I will tackle the sensor grounds soon I hope. 

 

This sure sounds like the OP issue.

Edited April 8, 20187 yr by dripley

Good luck. Are you just grounding each to a battery?

I am to use the article by @W-T posted 2 posts back to for the main computer grounds. It is definitely worth the read. Then I will open up the splice for the sensor grounds, see what it looks like and repair as necessary. Our issues are very much alike.