hello fellow Volvo drivers,

I came across issues not too long ago that, of course, was an unacceptable discrepancy. As I drove I would notice a slight bucking, or something that felt like perhaps a misfire or just a super-fast loss of power while cruising. Also this would occur after decelleration from high gear, the same thing. As time went by it became more and more pronounced and occured more and more often, eventually I would experience intermittent no-start situations...not acceptable.
Looking through resources and manuals for Volvos I traced it to a list of electrical components, for example: RPM sensor, power stage, ignition coil, and relays. I started with the RPM sensor as being most reasonably first to check. I would disconnect the sensor from the wiring harness connector and checked the terminals. I cleaned the connectors with electrical cleaner, and re-plugged and drove to test. This disconnection and reconnection and cleaning seemed to have done the trick...however.
The issue came back, the no-start occurance was a more-often experience and the bucking at cruising was not cool. I took it in the garage and started at it. Since I had started at the RPM sensor to which was in-fact the problem item, I began looking into it. Disconnecting and reconnecting the RPM sensor would work then not work, and the Volvo would not start. With the engine idling, I tapped on the connection point for the RPM sensor, and the engine died...narrowed down further. At this point it was either a faulty RPM sensor or perhaps the connector itself. I cleaned the RPM sensor where it goes to the bellhousing, it was riddled with metal particals. I cleaned it, but still something was not right; I started figuring perhaps I should go down the list of elecrical components. Then I remembered the tapping and the engine dying.
I pulled off the boot from the connector to look at the wire connections and terminals where I could not see...

this is was I found, the wire had been crapped away...by whatever ****.

So regardless of how, I had to fix this. And of course I had to fix it myself. I figured either to stick the wire back in the crimp and recrimp or solder. I bought a solder just in case, a good tool to have. At the time I did not know how to take the terminal out of the connector, so I had to half-*** the crimp by sticking the tip of a solder iron (conical shape, like the tip of a nail-0.125"DIA. at least) into the crimp to open it up, I then stuck the wire in and applied pressure with the solder tip at the side of the terminal/crimped portion. That was the best I could do, if you know what I'm talking about you have at best 0.125" space to work in. This fix did the trick, but not for long. The wire exevtually came back out, I had to do this correctly. Either I was going to re-crimp by taking the terminal out or solder the thing on! I asked around another good forum for Volvo and got a response from a darned good Volvo tech...

You stick a very thin screwdriver in the slot, try both, one is bound to work. I did it with a thin nail and pushed hard...

remeber the orientation when taking out, it only goes in the same way.

Now that I had the terminal out, it was just a matter of doing the job. I started just to re-crimp, which worked for almost a week, then it crapped out. You'd figure two plastic ties at the firewall would hold it secure enough to not giggle the wire out...perhaps its the tranny/engine. So at that point I needed it done! I soldered the **** out of it, hopfully this will do it.

Imagine this issure happening to those who pay huge sums to diagnose this to find nothing...what a b***h.

Hope this helps![/align]

 

you say gremlins....

I say entropy, my friend

 

Hello fellow Volvo drivers,

Also, with similiar symptoms of intermittent bucking and whatnot, check the 40 amp relays n the engine bays. Check the connectors and the wiring at the connectors. You'll be looking for exposed copper...not good.