V70 D5 lumpy after startup (briefly)
 

Hello,

When we had freezing temperatures not so long ago, I noticed that the V70 2008 D5 was taking longer to start than it normally would. It shook/rumbled for a few seconds after it started, then it settled and ran normal.

There was no light on the dash indicating a fault, but I decided to do a diagnostic check anyway. There was a fault code for cylinder 2 glow plug (not sure why that didn't put a light on the dash, but anyway!). Instead of replacing one, I decided to replace all 5 of them. I figured if one was gone, the chances were the others weren't far behind.

The car starts better since replacing the glow plugs and deleting the fault code, but it still has a bit of a rumble/shake/judder after initial startup for a few seconds, then it settles. What could this be?

I've done another VIDA scan, no codes are present. Its been recently serviced with a new fuel filter. I've checked around the injectors... there's no leaks that I can see. Battery voltage is fine. 163,000 miles on her, but its well looked after. I don't think 163k is high on a D5, but I understand that there may be wear in some components all the same. Its not going to be like new at that mileage.

Any advice/suggestions are welcome. The car drives fine and pulls like a train.

Can't offer advice but I can relate.

My 2008 xc70 D5 is doing the same. I will be doing the glow plugs before next winter.

I think mine has got worst since the swirlflap has stopped moving.

I recently gave mine and oil change, fuel filter and oil filter and air filter and it hasn't improved on cold startup. It's also had a new battery.

In case it helps: our 2011 D3 with 123k start-ups improved with new glow plugs (the previous owner or garage had installed the wrong ones) and a new 85Ah 110 battery (powerful).

Something that gets used during start-up may need a clean?

Its had new glow plugs and the battery is fine… That’s not old either.

I had a lumpy idle when cold with a good bit of blue smoke. Turns out there is actually an update available. After that, my idle wasn't lumpy and the blue smoke has totally disappeared. Volvo has had issues with the Euro 5 Diesels not running perfect upon a cold start in cold conditions.

If the rough startup is happening after the car has sat for a number of hours, and does the same when it is not cold, then it is possibly injector wear.

When the piston inside an injector wears to the point that it is no longer able to fully seal, it can cause the injector to slowly drip fuel into the cylinder over time.

When you next come to start the car, this causes two things 1) excess fuel in the cylinder causing a missfire and 2) loss of pressure between the high-pressure pump and the injectors, meaning it will take the pump a few seconds to get up to normal operating pressure.

Interesting. How do you clarify if this is the case or not? Have the injectors tested?

It only happens when cold. After its had a short or long drive and the engine has warmed up, it doesn't shake/rumble on startup.

08 D5 is the same,just a second before it picks up the last cylinder and smooths out, No codes. 132k miles.

Yes, you could remove the injectors and have them tested, but that's a lot of effort and costs money.

If you have access to (or you know a local garage that does) narrow borescope that will fit through the glowplug hole, that is a quicker way of checking. You should visually see a drip forming on the injector tip if this is the case.

Most of the cheap amazon borescopes are too wide, but they make automotive ones (such as Sealey) that are specifically narrow enough for a glow plug hole