Random P0335, P0300, P0302, P0305 Codes 98 V70XC

[StoningtonXC70]

The engine has been randomly throwing simultaneous P0300, P302, and P0305 CEL codes of late. They seem to have started after I had moved some of the ignition wires near the distributor cap and I'm thinking the wires may be getting long in the tooth. I moved the wire boots around in the cap over the weekend and now suddenly am getting the crank sensor P0335 code along with the other misfire codes. The engine starts and seems to run fine, never really notice any roughness or missing. The CEL will come on randomly and those codes will be there, now with a coincident P0335 twice in row. Is it possible that the multiple misfires are triggering the CPS P0335 code even with a properly functioning sensor?

Going to change the cap, rotor and wires as they are no doubt due based on time and mileage. One thing I'm a little leery of is the end-on mounting of the cap. Is there a small spring inside the cap that contacts the center of the rotor to the coil connector that is going to fall out in the process of pulling the cap? Had this happen once on a previous car's distributor cap.

Also looking for recommendations for ignition wires. Have not had good luck with Bosch premium wires on my 94 Escort, just had to replace a set that crapped out after a fairly short time/mileage. At least they had a lifetime warranty, so no charge for the replacements.

[Xilikon]

Get Bougiecord branded wires (which are oem), the only one which works properly. OEM is always the best choice.

[JRL]

and OEM plugs gapped NO LESS than .028

[StoningtonXC70]

Did the tune-up today using the FCP Groton tune up kit parts: Bougicord wires, OEM Bosch Volvo labeled platinum plugs, cap, rotor, and Mann air filter.

Prepped for the job by looking over the tutorials on plugs and cap and rotor on the Matthews Volvo Site which were very helpful. The cap and rotor tutorial is written based on a 97 850 GLT. One difference I encountered was that tutorial discussed what looked like a rather tedious removal of a vacuum switch that is mounted on, but is not otherwise connected to the side of the lower part of the airbox, on the 98 the switch is fastened with a plastic tab which easily popped of.

One thing not mentioned in the tutorials on MVS for either the plugs and wires or the distributor cap work was removing the metal pipe that is part of the turbo to intercooler plumbing that runs right over the top of the distributor. It was very easy to take off and later restore, and having it out of the way made it easy to extract the number five plug, and remove and install the plug wiring harness. Also gave me a chance to look inside the turbo plumbing to check for excessive oil, which was not present. Be sure to stuff a rag into the turbo port after pulling the pipe to prevent anything from falling in there!

I also disconnected the air mass meter from the upper part of the air filter housing so I could move upper housing out of the way as well. I did not need to remove the battery as described in the 97 GLT tutorial.

Withe the airbox box out it was very easy to get to the otherwise hard to reach bottom screw on the distributor with a 8 MM socket on a stubby screwdriver type ratchet drive. I think the MVS info says the cap retaining screws have a 7 mm hex head, but my original and new caps had 8 mm screw heads. Recommend using either a t-handle 3 mm hex key or one included in a multi size key with a handle to loosen the 3 rotor mounting screws - I originally used a long single key and it flew away to parts unknown when the first screw overcame breakaway torque and pooped loose - they were on pretty tightly.

Since I recently have been getting random P0335 crank position sensor codes along with plug misfire codes, I checked the wiring for the sensor. It looked like mice had been hanging out on the top of the tranny, and may have been chewing on the wire loom tubing on the CPS leads, as well as the other wiring down there, especially the wiring to the injectors. No damage indicated to the actual wire insulation, put in new loom tubing and taped up the wires. Cleaned and put fresh dielectric grease in the CPS 2 wire connector.

Car runs great now, no more codes ( or scary sudden intermittent jerking which started showing up up the other day while cruising at highway speeds when the codes got thrown).