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Well I finally found the problem and not surprisingly it was the ignition switch. Replaced it and BAM! Starts every time.
No cel. No codes. Just finally got a chance to turn the key on and off a few times. It had zero effect on it.
My brother who is a professional mechanic for Volvo noticed that it seemed like the timing was off a couple teeth. The marks lined up with the covers but not the static marks on the head. Well as it turns out, he was right. We took the timing belt off, put it back at tdc, and BAM it runs like new! We think whoever changed the belt did not line the marks up right when they put it back together. Thanks for your kind advice NCS.
[quote=”no_common_sense” post=144866]I’d want to hit that last wire with a scope and get a waveform of the signal wire. You probably don’t have a scope but you can try one thing with that last wire if you’ve got a decent voltmeter. That last wire is the signal wire from the ECU. The ECU uses that wire to tell the coil when to fire and it should be a black/red wire for #5. #6 will have a brown/white wire and #4 should be a brown wire. Those are the signal circuits for those cylinders.
Back probe all three of those signal wires at their coils with the key on, engine off. I’m not entirely sure what to expect the signal wires to have for voltage, but they might have a voltage there. What’s key is those signal wires should all have the same voltage. Use your Sesame Street logic and see if one of those wires is not like the others…in terms of voltage anyway. You might still be able to find a broken or shorted wire problem that way.
Keep in mind that you’re testing for a static voltage at best and there may not be a voltage reading there at all until the engine is running. The voltmeter might not tell you a useful story at that point. The voltmeter won’t be able to refresh fast enough to report an accurate voltage with engine running.[/quote]
I did the back probe test on the signal wires wih the key on. They all had the same numbers on my ohms meter. I have no idea what to do next..Thank you for your advice. I appreciate your thorough explanations. I did the back probe test with a good ground. No change. I did the back probe test from black/white wire to nearby good black/white wire. No change.
What now?I checked fuel pressure. It read 35 psi at idle. I am not sure what this means as I can find no source to tell me what the fuel pressure should be. I disconnected the fuel pressure regulator and the pressure went up 5 psi to 40. Can anyone tell me what this might mean? Is the fuel pressure high, low, or spot on?
Thank you all for your responses. The map sensor is all good, the egr valve is all good. Block test revealed no exhaust gasses in the coolant. I even bled the coolant. I suspect vacuum since it has fluctuating low vacuum when I hooked my gauge up. I did take the IACV off to inspect/clean and noticed there was a loose o ring inside of the valve. It seems that this o ring creates a seal when the valve is closed. Since mine was loose and out of place I am assuming that this is faulty and is most likely the source of my misfire at idle. Please correct me if you think I’m wrong.