97 S40 T4

MrsJPZ · Post by **MrsJPZ** » 25 Jan 2016, 11:33

Hello all,
Bit of a long shot but I wonder if any of you can help. I have a 97 S40 T4 that I have owned for a little over a year now and its never ran quite right, it came to me with a blocked cat, faulty camshaft sensor, faulty MAF and a what a was intermittent fault has turned into something quite regular with the symptoms of trying to stall on roundabouts/junctions, idling rough with misfire if revved, very rare engine cuts over 40mph, and jerking in 3rd and 4th gear at around 30mph. It recently had a full service in August and a new timing belt and water pump in October and has not been driven since.

I have taken this car to many garages since owning it and not one could find the fault(s) and I don't have access to vida/dice either.

Now I have started using another mechanic and he seems to think it's the pipes that is the problem, do any of you know the inner diameters for the vacuums? or any of the others? I have looked around online but I can't seem to find anything.

Any help/suggestions will be greatly appreciated.
Thanks in advance.

Post by **alschnertz** » 25 Jan 2016, 14:50

Yes, you should have your mechanic thoroughly check for vacuum leaks.

I wonder if your problem may be coil related.
When one of my coils went, I suffered misfire issues. I was fortunate to be able to see the "arc" marks on the coil body making it easy to identify.

MrsJPZ · Post by **MrsJPZ** » 25 Jan 2016, 16:29

The car also went through 3 sets of spark plugs last year after set number 2 I was informed that oil was getting in the cylinders especially cylinder 2 and cracking the plugs, the rocker gasket was the culprit so I had that resealed. It still gets oil on the coils but I am told that is because the PCV pipe that was just replaced is not seated properly and keeps blowing off, the original pipe blew off too.

The new mechanic just wants to replace all coolant, oil and vac pipes with silicone hoses and go from there, as a few are quite perished.

Post by **alschnertz** » 25 Jan 2016, 19:37

MrsJPZ wrote:The car also went through 3 sets of spark plugs last year after set number 2 I was informed that oil was getting in the cylinders especially cylinder 2 and cracking the plugs, the rocker gasket was the culprit so I had that resealed. It still gets oil on the coils but I am told that is because the PCV pipe that was just replaced is not seated properly and keeps blowing off, the original pipe blew off too.

The new mechanic just wants to replace all coolant, oil and vac pipes with silicone hoses and go from there, as a few are quite perished.

Has anyone actually diagnosed anything on this car? Or does the mechanic just want to start throwing parts at it.

Perhaps the PCV system is clogged. That would create excessive crankcase pressure which could cause oil leaks and hoses to "blow off". Has that been tested? It's a pretty common failure. What is not "seating properly"? What is there to seat? Most of the bigger hoses just slide on and are then clamped.

To me, starting with changing all the hoses without a diagnosis seems to be a waste of money. Why not try to figure out what's wrong first?

MrsJPZ · Post by **MrsJPZ** » 25 Jan 2016, 20:19

When the new PCV pipe going up near the coils was replaced the garage didn't fit it properly, its currently going over the head and not under - hope that makes sense, if it was daytime I would of got a picture to show you what I meant.

Garages have done diagnostics but the only faults that have been found was the ones I have already mentioned, other than the perished pipes and fitting the PCV pipe properly everything else has been sorted.

This mechanic wants to a full engine diagnostic the same time he changes all hoses, they need replacing anyway plus I would like them to be red.

But I do think it could be the PCV system being blocked but the mechanic thinks its unlikely but he won't rule it out just yet.

Post by **alschnertz** » 26 Jan 2016, 03:40

It's good that he's going to check the PCV system. You can do it yourself too. It's very easy. You may find this helpful...https://www.matthewsvolvosite.com/forums ... hp?t=57864

I'm curious about the "PCV pipe going up near the coils" and how that is re-routed. I think that's a molded piece and will only fit one way, yes?