If the problem is the MAF, then with the MAF unplugged the symptoms should go away. The car runs just fine with the MAF unplugged, except a little rich. Plug and unplug it with the engine off, not running. I will experiment with this tomorrow to hopefully rule-out the MAF, before my indie throws an...

Realize that as our old cars age, the wiring insulation inside the harness can become defective, the copper will corrode, and intermittent shorts can occur due to vibration and hot/cool cycles. Been there done that with the ECT, crank & camshaft position sensors. Just because you replace a sens...

I don't have access to another MAF unfortunately. They may have one at my indie, so I can put that #1 on the list to test first if you think it sounds strongly like MAF issues.

If I unplug the MAF, should it act the same or no?

Well. I replaced the IAC with a used one. Naturally it wanted to screw with me so it ran great for about 10 minutes! Then, right back to the exact same nonsense. Unplugging it didn't seem to help anymore either. ???? Maybe because it's in limp-home mode again? The only guess I have left is the wirin...

Urrrgggg. $300 and nothing was resolved. Naturally he chased the codes, and he replaced the baro sensor, which of course did nothing. The issue has gotten worse if anything. However , since it has gotten worse, I was able to test a bit and I think I found the issue. When I start the car, it revs up ...

Hey guys, I apologize. I greatly appreciate all the help you've given me, but sadly I just don't have the time or energy to keep whittling away at this. I scheduled an appointment with my indie who specializes in Volvos. Hopefully he'll be able to figure it out. I'm going to hand them a list of susp...

That little plastic connector between 1a and 1b is just a hollow tube, I am actually certain of that. Along those lines, disconnect at 1, plug the open end, see if the idle goes bad. Then the FPR runs without vacuum which would be an issue at high RPM but definitely not at idle. Unfortunately there...

I removed line 1 entirely from the FPR, put a paper towel under that and the disconnected vacuum hose. Started the car, let it run and watched, saw no fuel escaping. Revved the engine, went back under and saw/smelled no fuel on the paper towel. Does this rule out the FPR? Are we back to vacuum leak?...

I removed line 1 entirely from the FPR, put a paper towel under that and the disconnected vacuum hose. Started the car, let it run and watched, saw no fuel escaping. Revved the engine, went back under and saw/smelled no fuel on the paper towel. Does this rule out the FPR? Are we back to vacuum leak?...

I removed line 1 entirely from the FPR, put a paper towel under that and the disconnected vacuum hose. Started the car, let it run and watched, saw no fuel escaping. Revved the engine, went back under and saw/smelled no fuel on the paper towel. Does this rule out the FPR? Are we back to vacuum leak?...