Need some help folks. My son is several hundred miles from home with a load on the trailer and no power. He has called and said the truck will only get about 35 mph 8 lb boost max and just has no power. The problem started a few trips ago with a JD tractor loaded. He was pulling a hill and the truck fell on its face. We thought the problem might have been an overboost code so we installed a BD boost fooler on the truck before he left yesterday. The truck will run fine with an empty trailer, but has no power when loaded. FP is 12 @ idle and 7 lb @ WOT.

 

With no power and low boost it sounds like a turbo boot has blown off

 

Doesn't sound like a blown boot. He stopped for dinner and pulled the battery cables. cleared the check engine light from where he disconnected the boost sensor yesterday to install the fooler and now he can get up to 60 mph in either 4th or 5th. As soon as boost reaches 20 lb, it immediately drops with a corresponding loss of power. feather the throttle and speed comes back to 60 and the cycle repeats itself. The turbo was off a couple of weeks ago when the Jake brake was installed and the waste gate was working. Would a bad canister act like this? Why only under a load?

 

As I continue to search forums for low power, the subject of "limp Mode" continues to pop up but seems to be related to automatic transmissions. Is Limp Mode applicable to manual transmissions and what codes throw the ecm into limp mode?

 

No, there is no limp mode for manual transmissions.


phox

 

Sounds to me like the waste gate is just hangin up. Each time it opens up just takes it's time closing again. I am probably wrong on this but isn't there a vaccume hose on that turbo somewhere that might be the cause on this also.

 

Could the MAP sensor be bad it's the one that controls the boost. Or the waste gate actuator be sticking on the turbo.

 

Sounds like a sticking wastegate to me. Can you just disconnect the wastegate line and see if that works? I dont know a whole lot about these new trucks, but I think that would work if you had a boost fooler.

 

Well I think we can rule out the wastegate. Seems the boy plugged the line from the turbo to the wastegate and the truck surged real bad. Had to work the pedal back and forth to keep it above 45 mph. I'm beginning to dread a 0216 when we get the codes read. Either the VP or the throttle position sensor it seems. We did a APPS reset less than two months ago. Will having the batteries disconnected for a week or so cause the APPS to go squirrelly? Since this only shows up under a load, I'm beginning to fear its the VP (again)

 

If I understand your post, the truck would hit 60 until the manifold pressure came up and it got good and hot. That can be either the VP44 or may be the MAP sensor. The MAP could be grounding out when your manifold pressure gets above 20. That will shut down your fueling under load, and if it is bad the boost fooler will not compensate the signal either. Also, check your IAT sensor, and make sure it is clean and functional. Check the values of both sensors with the engine at operating temperature.

Your input fuel pressure is low, but within Dodge specifications. The problem with running anything under 14 at WOT in hot weather is that the VP44 will not properly lubricate and chews its delivery valve into small bits. On a Saturday driver that hauls plywood from Lowes, or on a daily commuter that runs mostly empty, that fuel pressure will never cause a problem, but load one up and you are begging for trouble.

 

I know this probly isn't it, but my truck would also loose power. It seemed like someone just reached over and flipped a switch. At least have a look. It would be amazing if this is all it was.

https://www.dieseltruckresource.com/...ad.php?t=81936

 

I had the IAT sensor out a couple of weeks ago and cleaned it with carb cleaner. I THINK it is working OK. Can you tell me how to check the MAP sensor and IAT output?