Some of you may be aware of my little conundrum shared in a previous thread here: https://www.brickboard.com/RWD/volvo/1627606/940/960/980/V90/S90/two_volvos_enter_one_remains_tale_cars.html

Anyway, at this point, after weighing many pros and cons, I'm considering keeping the 940, even though it's got 307K miles on it. I'll know for sure soon enough, but that's the way I'm leaning. Just to clarify, since I bought the 940, I have only been doing preventative and baseline maintenance. I haven't had the chance to drive it any more than on and off the trailer when I brought it home. So it was definitely a pig in the poke. I finished replacing the fuel filter and feed pump, some other deferred maintenance and hunted down vacuum leaks where I could find them. It now appears to start on the first crank, instead of the 2nd, and idles much more smoothly.

Initially, I found that the idle speed in park was about 1100-1200, regardless of whether it was warmed up or not. When shifting to Reverse or Drive, the high RPMs cause a decent clunk and a good deal of vibration.

I took the time to make sure the MAF was absolutely clean (even unbolted it from the air filter cover) and cleaned both ends and all wires with MAF cleaner. I re-checked all hoses providing vacuum to the intake manifold and the intake manifold gasket passed a cursory visual inspection, for whatever that's worth. Then I double checked and re-calibrated the TPS and idle stop screw to Volvo's specifications and I think it helped. The odd thing about the idle screw is that with the TPS properly calibrated, the idle screw, even if backed out to the point of not touching, wouldn't drop the idle to 480-520 RPMs, so that couldn't be helped. Furthermore, I noticed the idle was wandering a tad, so I took a rubber mallet and gave the IAC valve a few taps and, wouldn't you know, it smoothed out. It took a few more applications of the hammer to keep the result consistent, but I think that was a factor in my issues. This was sort of puzzling to me, because one of the first things I did was take it off and give it a good bit of carb cleaner and used electrical cleaner on the contacts for good measure. I also got into the holes with a few q-tips to wipe off excess carbon/sludge.


Overall, the idle is a good deal smoother than before, but the only thing that perplexes me is that regardless if it's warm or hot, the engine wants to maintain 1100 RPMs +/- 100 RPMs in Park only. In Drive, it's just about spot on at 750 RPMs. The only thing I've noticed is that when it's in Park, before shifting into Drive to test engine load, the application of the brake pedal seems to cause a 100-150 RPM drop in idle speed. The hoses coming to and from the master cylinder appear to be secure and in decent shape, so I don't know if that's a factor. Lastly, the idle is also fairly smooth when in Drive, but I do hear a bit of metallic vibration, which I'm unsure if it's something like a heat shield or the exhaust, which does have a muffler leak. Lastly, I don't know how old the gas is, or if it's premium, but I put in the corresponding amount of Techron FI system cleaner, which probably helped somewhat. Fresh gas with the remaining cleaner may be of more help.

That's about all the new information I have right now. I plan on registering and insuring it tomorrow, so I may find out more then. If I'm missing anything or if you have suggestions to share or perhaps confirmation that this is fairly normal behavior, that would be much appreciated!

P.S.: Not to inundate you great folks with too much at once, but I'm having a beast of a time removing one of the driver's side door handle "blank buttons" so I can get something out behind the A pillar trim. It's very loose and I can see the white clip and solitary screw holding it on, but it just won't budge, hard as I dare pry. Are there any reference pictures of the clip or any way I can remove it without breaking it?