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View Full Version : Sudden Power Loss/LHM... stuck in Aspen. No MIL or DTC


SkyGypsy
02-20-2019, 11:21 PM
After 30k long trouble free miles Iíve got limp mode once again. This time it is unlike the previous. Being that Iím on a ski trip in Colorado and have to head back to SoCal in about ten days, this is troubling.

It was 1degree Fahrenheit in Aspen Colorado when the van started fine in the morning to get some juice from the alternator. Went out and rode came back at 2pm to move it. 18 degrees now. Everything drove fine until I got to a light maybe a mile down the road. Stopped for red. Upon acceleration it revved pretty normally but then didnít seem to want to upshift. Revved high. Then it did upshift but power loss was apparent. I pulled down the road and cycled the key. No change.

It currently will upshift while driving but it has no boost and it doesnít seem to respond to me telling it to upshift. I have a OBD2 scanner connected to my phone that shows me everything. No boost. MAP around 69-75. I pulled the MAF sensor and confirmed the actuator arm is moving.

No MIL and no DTC reported on the OBD scanner. Trying to have a friend aid me in swapping sensors but I am under the assumption that if it were a sensor in the intake path it would clear when the key were cycle.

Iím reading through the LHM diagnostic thread but none of the descriptions sound quite like this. Any help is massively appreciated. Iím far from home.

Midwestdrifter
02-20-2019, 11:39 PM
Any anomalies in the live data? Can you get a real scanner?

NelsonSprinter
02-21-2019, 12:05 AM
No broken/split boost hoses or connections with oil spray? ie boost leak causing turbo shutdown
If dry hoses, I'd suggest disconnecting battery neg for 20 minutes and reconnecting to reset computer, assuming you have your radio code.

SkyGypsy
02-21-2019, 12:14 AM
Hose Connections all look good. No visible oil spray. Haven’t squeeze tested the hoses yet but they are all very new. Less thank 30k on them.

I wasn’t able to pull live data until I got it parked, so need to review that. But I’m not sure exactly what to expect from the live data. I haven’t reviewed it in quite some time while driving to know what to look I for.

Going to dive in full bore tomorrow. Currently have the negative disconnected and will get back to it in a few hours.

I’m not sure the turbo is resetting when I performed restarts.

DRTDEVL
02-21-2019, 12:22 AM
If you have no boost and the arm moves with the MAF disconnected, try driving with the MAF disconnected. It won't be full power, nor will it be the best fuel economy, but it can get you out of the mountains to a proper shop.

autostaretx
02-21-2019, 12:57 AM
MAP should not be above 32 psi at any time. (Manifold Absolute Pressure)

Depending upon your altitude, it should be about 14.7 (at sea level), and perhaps 11 psi at 9000 feet, with the engine just idling.

--dick

SkyGypsy
02-21-2019, 02:52 AM
MAP should not be above 32 psi at any time. (Manifold Absolute Pressure)

Depending upon your altitude, it should be about 14.7 (at sea level), and perhaps 11 psi at 9000 feet, with the engine just idling.

--dick

Isnít that boost? Which is measured in different units than MAP?

SkyGypsy
02-21-2019, 07:20 AM
I left the negative disconnected for a few hours. No change. I also tried driving with the MAF disconnected and it’s seemed like the power was the same with or without. It did seem to drive better than the initial occurrence this afternoon. Shifted well and all gears are useable.

I pulled some live data:

At idle
FRP 5419 psi
MAF 1.8 lbs/min
MAP 74 kPa
Boost 0psi

At load
FRP 13259
MAF 40.2 lbs/min
MAP 68 kPa
Boost -1.4 psi

After several stop start attempts it did not clear. I tried to cycle the key seven times but nothing changed. I don’t have power locks to attempt the full reset sequence laid out in the LHM troubleshooting thread.

I’m not sure what to think. There is a large quantity of frozen water beneath the airbox. I’m wondering if this may have disrupted the electronics somehow. I poured some deicer on it and drove around for a while trying to get it to melt. It’s single digit temps tho. So it didn’t all melt but progress was made.

I’m tired. Will resume tomorrow.

Aqua Puttana
02-21-2019, 01:30 PM
...

I’m not sure what to think. There is a large quantity of frozen water beneath the airbox. I’m wondering if this may have disrupted the electronics somehow. ...
Have you removed/checked the air filter? It may be iced over. Check that the air filter box drain is clear.

Check that the air filter box to turbo inlet isn't out of place or loose. That hose not being properly connected can cause some odd symptoms.

Double check that all sensor connectors are properly seated and clicked in.

New hoses are no guarantee against failure. Some brands have a history of infant mortality.

Good luck.

:cheers: vic

stormpeakco
02-21-2019, 02:18 PM
Seriously, very impressive correspondence by the sprinter-source community attempting to help this nearly stranded sprinter owner (whose ski vacation has severely been screwed).

It's getting closer toward the end of the week & it may be time to recruit/phone some local expertise....Dennis (an active contributor to this site) would know if the Glenwood Springs M-B dealership staff has significant sprinter experise....not a fun trip driving from the Roaring Fork Valley (RFV) over Vail Pass and out of Silverthorne up to the Eisenhower-Johnson tunnels at elevation in limp mode to Golden (vs. an ugly expensive tow).
Dennis may know if there is any Sprinter technician expertise in Rifle-Grand Junction (less than white knuckle drive, sans any significant mountain pass and virtually all down hill from the RFV and the direction, west towards home).

https://www.lindenautorepairgoldenco.com/
good luck.

Midwestdrifter
02-21-2019, 03:54 PM
Does the turbo actuator move when you unplug the maf? What does your ambient air temp, intake air temp, and map sensor read with key on engine off (cold).

SkyGypsy
02-21-2019, 04:57 PM
Does the turbo actuator move when you unplug the maf? What does your ambient air temp, intake air temp, and map sensor read with key on engine off (cold).

The actuator moves. With key on engine off and cold, the readings are
Ambient 20F
Intake 19F
Coolant 25F
MAP 75kPa

autostaretx
02-21-2019, 05:31 PM
75kPa is 10.8 psi.

Manifold Absolute Pressure, by its very name, is *absolute* (i.e. measured from zero psi/kPa), not "gauge" pressure.

If you were measuring Boost (pressure above ambient), that would be a "gauge" pressure measurement.

The ScanGauge reports MAP, since that's what the intake is really seeing.
If you have an OBD gadget that reports Boost, it's taking MAP and subtracting ambient pressure.

The Training documents we have call the sensor a Boost sensor (implying gauge measurement), but in the final paragraph on page 76 confirms that when the engine isn't running, the sensor reports ambient pressure to the ECM. That means it's an Absolute sensor.
refs: http://www.diysprinter.co.uk/reference/T1N_service_scans/075BoostPressSensor.jpg , http://www.diysprinter.co.uk/reference/T1N_service_scans/076BoostPressSensor.jpg , http://www.diysprinter.co.uk/reference/T1N_service_scans/077BoostPressSensor.jpg

When building such a sensor, the only difference between the two models is that an Absolute sensor's diaphragm is mounted on a sealed chamber, whereas a Gauge sensor's diaphragm other side is seeing ambient air (usually a visible hole or pipe on the back side of the sensor assembly)

--dick

Midwestdrifter
02-21-2019, 05:41 PM
The actuator moves. With key on engine off and cold, the readings are
Ambient 20F
Intake 19F
Coolant 25F
MAP 75kPa

That looks good. Hmmm. It seems your not building boost for some reason. Can you view your oil temp with your tool? If the oil temp is reported as really high, the ECM will limit power.

Can you access the TCM? It doesn't seem likely, but there might be a helpful code stored there.

Have you gotten a sprinter specific scanner on the van? Snap-on or Autel units used by many shops can sometimes do the trick. You might have a pending code that your generic dongle unit can't read.

I would double check the wiring harness near the EGR. The turbo actuator wiring runs through there I believe.


Also there is another pressure sensor (the ambient one) which is located on the air filter box. It is used to calculate boost (MAP minus ambient). That should match the MAP with the engine off.

SkyGypsy
02-21-2019, 07:43 PM
Thanks for all the help. The issue has been confirmed.

My turbo went.

Two of the intake impellers are cracked at the ends. The whole shaft is stuck. Going to start a new thread.

Midwestdrifter
02-21-2019, 07:48 PM
Tough luck. Thankfully you have a good chance of recovery.