No passing gear

sam1am

New member
So a few weeks ago I was coming up a mountain and the engine in my 2003 Sprinter T1N blew up. Breached cylinder - oil cap blew off, the works. Fast forward I got a new (used) engine put in by Mercedes. They called me today to tell me everything is working except for whatever reason it isn't shifting into "passing gear" which I understand to be when you floor it on the freeway it down shifts for a short period of time to give you a little boost to get up to a higher cruising speed (right?).

When he mentioned it I recalled that I had experienced that the day before my engine blew up. I was expecting it to go into passing gear at a certain point while I was driving it up this mountain but it didn't. I dismissed it at the time thinking maybe I didn't have the feel for when it shifts like that quite right.

So I have two questions:

1. Could lack of a shift into passing gear while driving up a mountain over-tax the engine to the point that it blows it up? I would think if it didn't shift into passing gear you would just slow down, right? When the engine blew up I was cruising at 65mph around 3000-3200 RPM IIRC.

2. What would cause it to stop shifting into passing gear? He said probably a bad shift module and recommended I just not worry about it because it would involve taking the transmission apart to fix.
 

sailquik

Well-known member
sam1am,
It's possible that lugging up the hill could have caused some issues.
So why did you not simply tap the shift lever to the left to drop out of OVERDRIVE and into 1:1 direct drive (4th gear).
You can shift your Sprinter up and down anytime you want. It will simply engage the lower gear, and if your revs are so
high that it would over rev to drop to the lower gear, the TCM/ECM will prevent that shift.
Use it more like a manual transmission and your Sprinter will be a lot happier with you.
Roger
 

MillionMileSprinter

Millionmilesprinter.com
Sam,
I downshift manually all the time, even when cruise control is engaged. Just tap the shifter to the left when you feel the need to downshift or when you see the LOD getting up in the 90's and you are climbing a hill. At least, that's what I do. (make sure you tap it back to the right when you are done, because it will STAY in whatever gear you tell it to)
Good luck with your new engine.
 

abittenbinder

Doktor A (864-623-9110)
They called me today to tell me everything is working except for whatever reason it isn't shifting into "passing gear"
That is a typical symptom of engine LHM.

Have the dealer read the fault code and repair the fault. Likely an electrical connector was not secured properly.

Doktor A
 

sam1am

New member
That is a typical symptom of engine LHM.

Have the dealer read the fault code and repair the fault. Likely an electrical connector was not secured properly.

Doktor A
They said it threw a code for faulty glow plugs (which they've run into problems getting out...grrr...), but no code related to the passing gear issue. Would the glow plug issue cause it to go into LHM?
 
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220629

Well-known member
... Would the glow plug issue cause it to go into LHM?
If an unusual electrical problem with the glow plugs affected other electronics then I suppose it is possible, but glow plug system problems do not normally put you into LHM. The Sprinter glow plugs are used for cold weather starting, smoke minimization upon startup, and in NCV3 newer models for DPF regeneration. Other than for the regeneration they are not needed once the engine is running.

The glow plug codes/issues are probably not your problem. I would look to other things. vic
 

lindenengineering

Well-known member
Can't say its the same but the engine MIGHT be running close to LHM with reduced fuel flow.
(Ref Andy's post)
I have one in at the moment. (2006 TIN)
Runs OK but is damn sluggish and won't kick down.
Scan date shows fuel flow very low but not enough to flag a fault code.
Job for Saturday morning at my shop.
Dennis
 

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