P1670 Immobilser error

[misha]

"R" will go?

[scot850]

Yes, the time has come after nearly 5 years and $20k+ in parts and labor. I hope when I get around to selling it, it will go to an enthusiast, but in the end of the day it is whoever pays the money.

My arthritis in my lower back makes it more and more difficult to get into and out of regular cars. My wife has an SUV, and it is so much easier to access for me. Also, I think a lot of the issues I have with the 'R' are due to lack of use. The car has only covered about 8-9000km in 4.5 years! It has now about 270,000km on it and when my wife retires in a couple of years, we plan to travel more and with a large puppy and another dog we will need more room. I will see how the base V70 goes once it is back on the road. If it runs well I might keep it as a back-up/beater car, but again with the lack of miles I do it will probably be hard to justify even that! Then there are all the parts, so many parts in our garage.......!

We may still have our '06 P2 XC70 (135,000km) that our son uses for a while longer though!

Neil.

[mrbrian200]

I'm talking about the ground rings underneath the plastic cover next to the coil packs, there's 2 or 3 of them, these ground the coil pack primary coils, weak grounds there will equate to a weak (or no) spark off the secondary to the spark plug(s), and likely trigger a CEL as one of the wires on coilpack pigtail is a 'health status' of some sort that goes back to the ecu. I soldered these ground terminals per method described here:

(post 30 Mar 2017 15:38)
viewtopic.php?f=9&t=80543&start=10

Because of oil contamination and galvanic corrosion simply getting it hot and touching it with flux core electrical solder won't do it: Just not enough flux in that to clean the metal so that the solder bonds to and creates a solid electrical contact. You'll also want to clean/lightly sand the actual rings and the areas around the bolt holds on the head where they sit with 800-1000 grit sandpaper or a fine wire brush.

Also if you use a small torch practice heating/soldering on some spare stranded wires not attached to the car first: if you get copper too hot it oxidizes and solder wont stick to it no matter what you do, so you'll want to get a feel for it/practice before doing it on the car where you need it right the first time.

As you replaced the coil pack and still are seeing an intermittent issue I would do this first. If that doesn't make a difference then I would look at the pigtail for that specific coil.

[mrbrian200]

I'm not sure these coilpacks fail quite as often as many people believe. I support the notion that their spark output may decrease slightly over time. However, I also suspect harness electrical connections which can also degrade form a compounding factor, short of which spark output would still be within spec in many cases not marked by sudden death or sensitivity to moisture. Conventional wisdom is that these be changed roughly every 10y/100k mi. I'm not convinced on that. I did replace the insulator boots and spark plugs.

[scot850]

4/5 of the coils that were on the car had cracks in the bodies. There was also some brown gooey residue around the top of the boot. Some suggestions are that this may be coil wire insulation leaking from the cracks reducing the coil effectiveness. I plan eventually (one of many projects) to find a flexible non-conductive temp resistant sealant to fill the cracks and keep the coils as spares as they were working ok as far as I can tell. One of the coils was a non-Volvo un-marked one in cyl#1 position. It was un-cracked.

I am returning the 'faulty' new Volvo coil to Swedish Car Parts along with a 2nd one that has been damaged in the connector area in transit (broken piece found in the bubble pack wrap).

For the moment the car is not showing any codes!

The wiring in the top part of the engine gets very brittle over many years and moving them at all can cause the wire coating to crack and short or just break. I carefully handle the harness when re-covering it with flexi-pipe to help insulate it. I am surprised there is not a quick release connector that would allow you to swap out the whole harness (maybe there is and I don't know that).

The question I did ask for clarification, is what ground wires were you talking about? The 2 in the top of the head between the coil packs? And if so, did you completely remove the rings on the ground wires and re-solder them back on, or did you clean them and run solder over the joints?

Neil.