Misfire Cylinder #3 AGAIN! It's a full time job

NcTrooper10722001 · Post by **NcTrooper10722001** » 07 May 2010, 20:03

1996 should have an OBD-2 computer.. Is the code PO303 ?? Im thinking possible intermitent ( did I spell that right? ) fuel injector on #3 or coil quad driver, if applicable in computer.. ??? Good luck on that one..

hollywood953 · Post by **hollywood953** » 10 May 2010, 14:20

well, the check engine light came back on today, the code is p0303 as you mentioned. It seems sosmewhat to be after it sits for a while. The light came on this morning on my way to work. After work it was still on but running fine. is there a way to test one injector? Also, maybe important maybe not but it runs poorly when the car is in reverse. Any ideas now?

hollywood953 · Post by **hollywood953** » 12 May 2010, 14:43

finally got some time to work on this again. I pulled the spark plug on cylinder 3 it has a lot of soot around the bottom of it. the one I removed is not like this at all. The piston top is black as well. also, the wires to the coil pack are stretched very tight, almost like they shrunk up. can I extend them? This sounds like a spark problem to me or is it air?

NcTrooper10722001 · Post by **NcTrooper10722001** » 12 May 2010, 17:29

Try a compression check on that cylinder ( should be 125-150 psi ) let us know what U find

newchapterinlife · Post by **newchapterinlife** » 24 May 2010, 19:40

i am having the same prob on my 97 850
mis fire on cyl #3 . The plugs were black and suity. the engine light went off and i put in lucas in tank. problem is back. ???? n e suggestions>?

hollywood953 · Post by **hollywood953** » 24 May 2010, 20:07

as you can see this has been a big problem for me that I am not convinced is fixed. I changed the coil pack on #3 and it went away for 3 months only to come back. What I would do is check the wires going to #3 and see if they are frayed. I ended up taking the connector apart and giving the wire a little more slack then reconnecting it. If you have soot on all spark plugs you are getting too much gas most likely and since there is no choke it is probably either the MAF sensor or a clogged air filter. Get the code cleared and switch the #3 and #4 coil pack and see if it now gives you a misfire #4. If so it's the coil pack. After that is clear unplug the MAF sensor and see if it runs better without it. If so try using some MAF cleaner it's about $4. I am on eastern time so if you need other help reply or e-mail me and I will try to help. These guys are great.

newchapterinlife · Post by **newchapterinlife** » 29 May 2010, 19:52

try replacing the dis cap and the dis button and the wires. the prob will be resolved

DanR · Post by **DanR** » 30 May 2010, 08:40

newchapterinlife wrote:try replacing the dis cap and the dis button and the wires. the prob will be resolved

Like your 850, there isn't a distributor or spark plug wires. The white engines of volvo are coil on spark plug, all electronic.

The person with the problem needs to do a compression test to rule out a bad valve.

DanR '94 964 352,000 miles (117,000 on the new engine)

Hkanitz · Post by **Hkanitz** » 09 Jun 2017, 05:50

Hey, I just went through this with a 1995 960. Intermittent misfire. Definitely check the power stages. They are on the bottom of the intake. One front one back. One is for odd #, the other is for even#. Mine failed on #2 which is the rear. Found one on ebay for like $12. It is also called the ignition module. Do yourself a favor do like previously mentioned by someone before me, and switch them, problem will go to even cylinder. Do it, do it now quit wasting your time! Hope this helps! Peace!

4cornersfan · Post by **4cornersfan** » 02 Sep 2018, 18:37

I am having exactly the same problem with my 2004 S80; intermittent misfire on cyl 3. Did you ever resolve the issue?

Misfire Cylinder #3 AGAIN! It's a full time job

Re: Misfire Cylinder #3 AGAIN! It's a full time job