I believe this is related to my low power and P0237 issues but last evening I went and picked up a new boat 20 miles away. Idk when it started but i started hearing a lot of what sounds like valve chatter. Something tells me it has nothing to do with the valves but that it’s related to a timing issue. I’m also having rough idle symptoms again although a bit different from when I had air in fuel. What I’m thinking is since I have turbo play and all that i may have low boost which flipped the code and is causing low power. I also read somewhere here that low boost will create more timing and make a knocking noise and higher boost will retard timing. 

 

This boat I bought is a 16foot aluminum boat. It don’t weigh much at all but o the way home going up a 5% grade the truck was very sluggish and I kept loosing speed in 6th gear going 65 up the hill. Also the turbo instead of making a whistle when I stabbed the throttle going up the hill it made more of a lower pitched whine. Any one else think my issues are related to the turbo? 

Also would a boost leak tester provide the results needed to condemn the turbo?

 

Possible Causes

• Other DTCs
• Boost Pressure Sensor
• 5-volt Supply Circuit
• MAP Signal Circuit Short To Ground
• MAP Signal Circuit Short To Sensor Ground
• MAP Sensor
• Intermittent Wiring Problem
• ECM

No listing of a turbo there. So you need to go over the P0237 code diagnostic carefully. Basically if the MAP sensor is throwing the P0237 its in LIMP MODE. The ECM can no longer detect boost pressure so the turbo will not spool.

Edited April 13, 20187 yr by Mopar1973Man

Just now, Mopar1973Man said:

 

Possible Causes

• Other DTCs
• Boost Pressure Sensor
• 5-volt Supply Circuit
• MAP Signal Circuit Short To Ground
• MAP Signal Circuit Short To Sensor Ground
• MAP Sensor
• Intermittent Wiring Problem
• ECM

No listing of a turbo there. So you need to go over the P0237 code diagnostic carefully. Basically if the MAP sensor is throwing the P0237 its in LIMP MODE. The ECM can no longer detect boost pressure so the turbo will not spool.

I have been slowly going thrubthat diagnostic. So far the code ya not comeback but I did unhook the boost fooler. It’s not in limp mode becuase when I had the edge ez it would trip this code when I was fiddling with it andnit would be a major dog. It’s nothing like it was that time. 

Sound like you got a possible boost fooler issue then you need to head towards that Quadzilla soon.

 

As for testing the MAP circuit in a nutshell. 

 

Unhook both end MAP sensor and the ECM. Now ohm test from end to end. A passing grade is <5 ohms.

Leaving both unhooked now go from pin to GROUND. A passing grade is infinite ohms.

Hook up the ECM lead turn the ignition ON engine off test the 5V pin. Make sure you got 5.00V present on that pin.

 

Leave your current boost fooler out of the circuit and just hook up your MAP sensor. Clear all your error code go for drive. If no codes are thrown then that circuit is good you should be able to reach 19-20 PSI of boost without a boost fooler and possible rise slightly pass and feel the defuel kick in without codes. I typically still reach 23-25 PSI without codes but it dog out above 20 PSI for me and struggles to build more boost. This is normal. 

Just because the code has not come back does not mean everything is cherry.  The map sensor could still be giving a false reading, but it could be within the ecm's specified range and would not trip a code.  You're having plenty of symptoms related to a false map reading, just as @dripley and others have had.

2 minutes ago, trreed said:

Just because the code has not come back does not mean everything is cherry.  The map sensor could still be giving a false reading, but it could be within the ecm's specified range and would not trip a code.  You're having plenty of symptoms related to a false map reading, just as @dripley and others have had.

I think you are right. I did go ahead and order a map from Cummins. 

 

6 minutes ago, Mopar1973Man said:

Sound like you got a possible boost fooler issue then you need to head towards that Quadzilla soon.

 

As for testing the MAP circuit in a nutshell. 

 

Unhook both end MAP sensor and the ECM. Now ohm test from end to end. A passing grade is <5 ohms.

Leaving both unhooked now go from pin to GROUND. A passing grade is infinite ohms.

Hook up the ECM lead turn the ignition ON engine off test the 5V pin. Make sure you got 5.00V present on that pin.

 

Leave your current boost fooler out of the circuit and just hook up your MAP sensor. Clear all your error code go for drive. If no codes are thrown then that circuit is good you should be able to reach 19-20 PSI of boost without a boost fooler and possible rise slightly pass and feel the defuel kick in without codes. I typically still reach 23-25 PSI without codes but it dog out above 20 PSI for me and struggles to build more boost. This is normal. 

Currently the filier is not I. The circuit. I’ll try that testing as soon as I can. Gonna have a busy weekend. Could a false map reading cuase a rough idle?

8 minutes ago, Mopar1973Man said:

 

Sound like you got a possible boost fooler issue then you need to head towards that Quadzilla soon.

 

 

Coming as soon as I can scrounge up the cash! 

1 minute ago, Marcus2000monster said:

Currently the filier is not I. The circuit. I’ll try that testing as soon as I can. Gonna have a busy weekend. Could a false map reading cuase a rough idle?

No, due to the IVS in the APPS.  Once the IVS is triggered, the ECM switches to an idle state where it ignores sensors.

3 minutes ago, Marcus2000monster said:

Could a false map reading cuase a rough idle?

 

MAP sensor has nothing to do with Idle. You can be missing the MAP sensor and it will still idle fine. 

Hmm I wonder why it started idling rough all the sudden. I was right at 1/4 tank of fuel when it started. Thinking it may have been sucking more air I filled up butnjbhavnt drive fR so we’ll see if it clears up. 

Sorry  guys I had a crazy weekend and didn’t get a chance to work on the truck except to throw in that new MAP. I’m headed to the British Virgin Islands today on a business trip with Dad so won’t be able to work on her his week either. Got the new map in and didn’t make any difference as far as power. I pulled a 30 ft RV last Saturday and truck was pretty gutless especially in a hill. I called up Matt from Diesel Auto Power and he thinks my turbo is not building proper boost and suggested i rebuild it being there is oil inside the housing and some minor shaft play. Went ahead and ordered the kit and hope to get that done next week when I’m home. Truck also has a intermittent very light rough idle again. What can cuase a rough idle besides VP and injectors?

41 minutes ago, Marcus2000monster said:

Truck also has a intermittent very light rough idle again.

 Only when the engine is fully warmed up right? If so the injectors are to blame. 

16 minutes ago, Mopar1973Man said:

 Only when the engine is fully warmed up right? If so the injectors are to blame. 

I think that’s correct. I may try reinstalling my injectors with the info from the other thread. 

That's a start. If still giving you problems. I'd have them re-popped tested and check for flow rates again. I hate to admit it I had one set of DAP injectors that fell off set pop and needed to be redone. It happens. I want to take my current set this summer and repop to 315 bar and run them. First I need the steering fixed. 

16 minutes ago, Mopar1973Man said:

That's a start. If still giving you problems. I'd have them re-popped tested and check for flow rates again. I hate to admit it I had one set of DAP injectors that fell off set pop and needed to be redone. It happens. I want to take my current set this summer and repop to 315 bar and run them. First I need the steering fixed. 

I wondering that my not be what happened. It ran fine ever since the air leak got fixed. What’s standard pop pressure? 

Have you checked for boost leaks at all?

16 minutes ago, trreed said:

Have you checked for boost leaks at all?

No sir. That’s next on the list. After the rebuild.

Why not check before rebuilding? That could be the whole issue.

3 hours ago, notlimah said:

Why not check before rebuilding? That could be the whole issue.

I’ll do that! Got to wait till I get home from the Virgin Islands first haha

@Marcus2000monster enjoy the BVI's. Went there in 01 for a sailing charter. Have a few painkillers for me. 

 

L8tr

D

11 hours ago, SilverMoose said:

@Marcus2000monster enjoy the BVI's. Went there in 01 for a sailing charter. Have a few painkillers for me. 

 

L8tr

D

Hey I done did that! Haha It was a bit strong but not bad! Lol 

There is it of hurricane damage here right now. 

 

L8tr

D