Well that's good to know. The electrical conections are all intact, though the battery terminals could use a little cleaning. The thing is though, with my "misfire", the car starts up just fine and sounds normal. There is one slight abnormal noise, but it goes away after a few seconds. My slow O2 sensor response doesn't pop all the time, in fact it hasn't popped the past few times I have scanned the CEL.

Since the codes that show up give specific cylinder(s), usually 3 and sometimes 5, could it be an injector or compression issue?

Like I have mentioned before, when I brought it to my mechanic he saw nothing wrong and that the car runs great. He's clueless as to where this "misfire" is coming from.

What should be done next?

 

Well, my misfire ended up being the PCV line (from Oil Separator to PTC); it was disconnected before the PTC. In other words I was venting into the atmosphere (explains the stink), and was sucking unmetered air into the intake. Plus something else too (related). Its fixed temporarily for tonight, in the dark, parked on a major Avenue. Tomorrow I will get a hose and clamps and fix it.

On your case: it's very rare for several injectors to fail simultaneously. Same for compression. Sure you can do a compression test. They should be above 150 with no big variances between each-other.

I would go back to the vacuum test -- click on the website link on my previous post and check with the Vacuum Gauge which "Scenario" is yours. Some vacuum leaks are not easy to find. Start simple....

 

Stink as in oil? There's a strong smell of something while standing outside my car and when driving with the windows down, but I never took the time to acually smell what it could be. I'll check it out in the morning. Maybe I have the same problem as you but I checked everything, making sure it's hooked up. When you started your car up, did you hear a grogging noise and did it go away?

I may test the compression if it gets to that point. I talked to someone else and they also said that the injectors failing is a possibility, but very rare.

 

Yes - stunk as burnt oil. Took it around the block, much less smell. Since I had oil sprayed all-over from the busted cooler lines, I thought that the smell was oil being cooked on exhaust, engine, etc.

I don't know what you mean by "grogging". It may be the lifters, which is normal for our cars on start-up. Yes, it goes away. Take a video and post it on Youtube...

 

Hmm, it's probably just the lifters then.

I'll hook up the vacuum tester tomorrow morning and check it again using the link you provided.

 

After lubing the throttle cable up due to it sticking, I tested the vacuum again. It started off at 15 then decreased to a steady 14. There's no signs of an "abnormal scenario" from the vacuum link provided by Henry10.

 

Another simple thing -- are the spark-plugs gapped correctly (about 0.028")?

 

I will check tomorrow once I pick up my new gapping tool.

 

People here and VS report problems with Platinums or other "upgraded" plugs. So I would (and do) Bosch or Champion copper ones work well.

Re-gapping got rid of some misfire for me.

 

What brand is the tune up parts that were installed?
Cheaper brand ones can cause issues.

 

I had OEM Volvo plugs in, but I don't know how to check the gap of 3 pronged plugs. I assume they would have came pre-gapped anyways

When I went to get a new gapping tool, I ended up buying new plugs. They're NGK V-Power. The gap was about .033" out of the box, so I had to decrease the gaps on all five plugs.

I reset the codes, so we'll have to wait and see if any pop up. I should know by the end of tomorrow after class.

I started with OEM Volvo plugs, but just put the NGK V-Power ones in today. NGK plug wires, Bosch cap and rotor, and an MSD coil.

 

On the cap and rotor is it the bottom of the line one or the high line one?
Did the cap have the black cover on it with the cylinder numbers on it?

 

Like Tech said -- go over the Distr cap again. It's not impossible to screw it up. Check also that wires are seated well.

On the spark-plugs: You can also get Bosch or Champion (copper) at any local store. Don't get too fancy. Copper works well. Volvo RWD guys do not like V-Powers.

https://volvoforums.com/forum/volvo-...gs-ones-47367/

 

I did fix my PCV lines today and some other vacuum lines. Car is back to normal, well not exactly -- Flex pipe just got busted yesterday. I am trying to nurse it while I am doing some work on the V90.

Maybe I will give the flex a try with a temp fix -- although they never work for more than 5 miles... Although taking it out did not seem too complicated, but I could be wrong...

Now that I writing this -- I think I have flex somewhere in my parts bin. It's a lot longer -- we'll see.

 

Here is another link to spark-plug discussion Bosch Platinum Plus-4's - Turbobricks Forums

 

I didn't know Bosch made a bottom line and top line cap. However, the one I have does have a black cover with the cylinder numbers.

All wires are are connected to their respective spots on the cap. They're also seated good.

I originally went to Walmart for plugs and a gapping tool, but they only had Autolite. I started out with Autolite when diagnosing this misfire. They did nothing. I went to Pep Boys and all those stores (Pep Boys, VIP, AAP, Autozone, and Napa) keep their plugs behind the counter; all they had was NGK.

What's wrong with the V-Powers? Just wondering.

 

Some people think that V-groove or U-groove is just hype. Like some other cars, Volvos want what they want, and while V-grooves may be the sweet-spot for other cars, our Volvos like Bosch and Autolite Double-platinum.

I am not sure where you are with Stages (0, 1, etc). If you are around Stage 0 -- bring your car to spec, then later start to move up the food chain.

 

Hmm, good to know.I guess we'll have to wait and see if the CEL comes back on. Then we can go from there. Perhaps going a little less on the gap if it does? Say .026"?

 

CEL already came back on, p0300 and p0303. The car seems to run a little smoother, its less rough when idling.

 

I run Autolite coppers in mine and running 15PSI boost I drop the gap to .025 for the higher boost.

Yes Bosch makes bottom line and top line. The bottom line one does not have the black cover on it.