Low Compression In Every Cylinder!?


New member
It's been a long journey with trying to diagnos my 2005 non starting sprinter. We finally did a compression test after throwing an embarrassingly high number of parts at the fuel system, and all cylinders are coming back under 200psi. The van is currently sitting at a dealership in the Bay Area awaiting a possible tow to a place where I can eventually piece it out for sale unless there's something else I can do to fix it.

Any suggestions on next steps for determining exactly what this motor needs?

The van has been sitting dead for 5 months, is it possible to get an accurate compression test after that?

Some of what we did/ found:
Replaced battery
Replaced fuel filter
Replaced glow plugs
Replaced injection pump
Replaced fuel rail
Replaced 1, 5 injectors along with one of the hard lines

We pulled the #1 and #5 injectors and found rust on the injector tips.
Low compression across all cylinders (I'll get the exact numbers).


Well-known member
For info
Minimum pressure to light a fire is 315 psi.
Normally a new engine will be developing 400 psi with turbo charger--(normal aspiration is 450!)
You are allowed 15% max drift between cylinders and 25% drift on the spread

The only way to determine the problem is a tear down!
I suspect your engine has glowed in the dark due to bad cooling a very "popular" cause of overheat related failures.


Well-known member
Well assuming its std cylinder bores!!
It demands a teardown and a rebore with new pistons.
A piston set is $1500 and re-bores are about $50 per hole so $250 for that alone!


New member
the SD Europarts engine rebuild kit including new pistons is $1800. This is of course just parts and you will need bunch of machine work. for another $1750 you could pick up a brand new head which may be only a little bit more expensive than having a machine shop do a full head refresh. Guessing a rebore and hone could easily run you $1000. The last 4 cylinder engine block I had bored and honed was $400 i think...different machine shops different prices

Aqua Puttana

Poly - Thread Finder
Maybe a dumb question.

Is it possible for a wet test using some oil to help determine whether the rings are the problem? I suspect that keeping the volume of oil to a minimum is critical given the compression ratios.


Oops. I may be able to answer my own question. The oil can be ignited as fuel and possibly cause a mini runaway. :bash:


Possibly some type of leak down test?



New member
Ok so the compression test results were:

C1 100
C2 240
C3 140
C4 160
C5 120

Rpm 245

I should mention that I was experiencing occasional hard starting. When this would happen, disconnecting and then reconnecting the fuel pressure sensor connector at the back of the fuel rail always fixed it immediately. The van died a few times while in motion, and again the sensor trick worked to restart. Is this related?

Aqua Puttana

Poly - Thread Finder
Something is rotten in the state of Denmark.

Oops. That brand new saying is likely un'PC these days.
Or maybe not.


You don't give any details of the previous symptoms. Those are extremely low pressure readings.

Rust on the tips of the new injectors, or those that were removed?

Did the engine just die without some noise or warning? It seems to me that it would not start long before the pressure on all cylinders was that low. Was it running fine until it just didn't start one day?

Perhaps bent valves? Have you checked that the timing chain moves when cranked? Easy to see when the oil fill cap is removed.

Are you certain that the compression testing is being done correctly?

Have you tried a whiff of ether during cranking as a test? Normally ether use is discouraged, but it can be a useful test tool. Just don't get hooked on the juice if it works.

:2cents: vic
Last edited:


New member
Aqua thanks for your reply.

The rust was found on two that were removed and replaced after a test of some sort. Leak down possibly. I can find out if this is important info. 1 and 5 were replaced.

The engine was running fine until it appeared that I'd run out of fuel. The engine just stopped and wouldn't start. I was headed to get fuel, went around a corner, and the engine quit without any symptoms or noise. She was running perfectly except for the occasional hard start/ fix by removing the pressure sensor.

I haven't checked the timing chain but will in the next couple of days.

I don't know if the compression test was done correctly. I have the van at a dealership in the Bay Area. The tech seems competent.

I haven't tried ether but will.


New member
OK so I had a chance to try to start the van which was only cranking it 85 RPM so said the scangaugeII. Obviously this is way too slow. The battery has been dead in the shop brought out it's jump starter battery. Could this be a starter issue? By the way the timing chain looks fine and was spinning in sync with the motor.

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