1998 V70 XC AWD Random Misfire. P0300, P0302, P0304, P0305

[jblackburn]

Easy fixes are the best! I'm glad that worked for you

[v70xc]

Once I put a few more miles on it I will return to report... all good I trust...
I don't think I would have even thought of rerouting the wires as a fix...
You guys are really on the ball... thanks again....
I will report back in a few days...

I am more curious than ever now... Do you think that the sensor was just sending off bad reports to the computer and not actually having any effect on the firing time… or could these misrouted wires have actually been causing the computer to attempt to adjust something in the firing time and in fact causing a true misfire sequence? Thoughts?

[v70xc]

Well... I think you did it. Thank you.
Over 300Km since my last post and I have not had a P0300, P0302, P0304 or P0305 code yet.
I guess by having the crankshaft sensor wires too close to the distributor cap did cause false codes to be set.
Thank you so much for all the help.

Now onto other thoughts.... should go to another thread.... Got P0440 after gasing up today. Cleared it, another 150Km and no other code set.
Guessing it is time to check Evap items.... what ever and where ever they are...
Thanks again for all the help
Chat you soon

[jblackburn]

Congrats, glad you fixed it!

[cn90]

There are many many threads on misfire, but I want tobring back an old thread.

My 1998 S70 GLT with 152K miles just showed these EXACT same codes as the O.P.: P0300, P0302, P0304, P0305.
- Car runs fine with no issues at all, normal acceleration etc.
- Stage Zero done Dec. 2012 (brand new Bosch copper spark plugs, Bosch cap/rotor, Bougicord). PCV overhauled, no vacuum leak. Used only "good gasoline".
- MAF was last changed at 65K miles. But no MAF codes (yet).
- New Fuel Filter.

I just erased the codes and see if they come back.

I am wondering if one of these is a culprit:
- Crank Sensor (or wire routing issue as the O.P said)
- MAF
- ? Bad Gasoline
etc. etc.

Any insight will be appreciated.

[v70xc]

Jblackburn has been my saving grace in regards to this issue and many other items I have attempted to address in the pass. Thank Jblackburn
Like he mentioned previously...zip tie the cam/crank position sensors away from the distributor coil wire ... these are found around the BellHousing. My fix was that easy.
The pictures I posted on 01 Dec 2010, 15:14 should show you exactly where they can be found on the make and model of my car.
I certainly hope your fix is as simple as mine.

As a side note. I tried to save a buck or two at one time and used some other brand of spark plug cables. That was a terrible mistake and cause numerous issues to come and go. They remained on the car for 150Km and I promptly replaced them and found all the other odd ghosts and gobblins to be gone. That being said, I only run "Volvo spark plug wire set (850 C70 S70 V70) - Bougicord (OEM) 9135700"... I believe this is the set I ordered from http://www.FCPeuro.com for my 1997 V70XC AWD Turbo 2.4L. In the same train of thought, only use the Volvo branded spark plugs and the recommended bosch distributor cap... all for the same reasons.

One time I used regular gas in the car and had a noticable change in the ride but no codes. For that reason, I have used nothing but Supreme at all times.

I am assuming you have verified that you have installed all the spark plug wires in proper sequence on the distributor cap? This will give misfire codes as well.

Again, best of luck and hope this helps. Please keep us posted with you progress

[cn90]

Thanks v70xc,

I did the Stage zero back in Dec. 2012.
The codes only appear now 7 months later.
I will try to re-route the Crank Sensor wiring and see how it goes.

[cn90]

So I followed the advice of re-routing the Crank Sensor wiring. The wiring was approx. 1cm from a spark plug wire, no biggy. But since people advise me to re-route it, I change the wiring route, so the CPS wiring is away from the spark plug wires.

In the process of removing the Top of Air Filter Cover, I discovered something interesting...
- I already did the "SAS Delete" using the 99-cent Radio Shack diode last Dec 2012.
- When I opened the Air Filter area, I saw traces of rusty water on top of the air filter, with some flowing across to the other side. I don't think it was much water because the discoloration on the air filter was not that bad.
- This rusty water certainly came from the Air Pump, which I have ignored since I bought the car in Dec. 2012.
- So I did the usual thing, I drilled a hole at the bottom of the Air Pump, and sure enough a gush of rusty water came out!!!

See the photos for your eyes only...

Airpump01.JPG (47.83 KiB) Viewed 2265 times

Airpump02.JPG (95.27 KiB) Viewed 2265 times

[v70xc]

How far are the wires from the distribution cap now? 1cm could have caused the miss fires. Let's hope that moving the cure the problem

[cn90]

The CPS wiring is now 5-6 cm from the spark plug wires.