Replace Distributor Cap & Rotor Volvo 850, S70, V70

How to change the distributor cap and rotor on a 1997 Volvo 850 GLT. This job requires removal of the battery and the bottom half of the air filter box.

Volvo Distributor Cap

Lets talk about replacing your Volvo Distributor Cap & rotor.

Overview: How to change the distributor cap and rotor on a 1997 Volvo 850 GLT.

This job requires removal of the battery and then the bottom half of the air filter box in order to reach the bottom screw on the distributor cap. Including taking the photos, the whole job of removal and replacement took 2 hours (first time).

1) Common tools: a standard screwdriver for the distributor cap screws and a wrench or socket to disconnect the battery terminals.

Less common tools: You will need a 3mm hex key (pictured below left) for the rotor and a slim ratcheting driver with Torx bit (pictured below right) for the vacuum switch.

2) Remove the battery. (Note you will have to re-type the code for your radio after reconnecting the battery.)

3) Disconnect and remove the flexible air intake tube, seen above. This tube attaches to the bottom half of the airbox and the front of the car near the radiators. It doesn’t have clamps (at least mine doesn’t).

it just pulls off at each end.

4) Disconnect the ignition wire running from the coil to the distributor cap. It is held by two clamps built into the airbox. This will allow the airbox top to be lifted up and out of the way. The wire can be seen in the picture below.

5) Disconnect and remove the two Torx screws holding the vacuum switch to the side of the airbox nearest the distributor cap. It’s a tight fit. Note: there is no need to disconnect the three vacuum hoses from the switch. The picture below is taken from directly above and shows a slim ratchet in place for loosening the two Torx screws.

6) The picture below shows the vacuum switch after unscrewing and removing the two Torx screws. In this picture the electrical cable was disconnected (connector visible at bottom), but after doing the job I realize that it was not necessary.

7) Disconnect the metal clips that hold the top of the airbox in place and remove the bottom half of the airbox from the car. Remove the air filter at this time. Next, remove the bottom half of the airbox. This can be done by pressing down on the two clips at the corners near the engine and lifting up and pushing towards the center of the car. The third pin at the side of the box near the wheel will disengage out of a rubber bushing and allow the bottom half of the airbox to pull out.

8) The picture below shows the top of the distributor cap (still covered with ignition wires) and the disconnected vacuum switch. With the bottom half of the airbox out of the way, there is now enough room under the top of the airbox to reach the bottom screw holding the distributor cap in place.

9) After unscrewing the distributor cap, label and remove the ignition wires and pull the distributor cap out. I took the precaution of marking the old distributor cap with labels for each ignition wire and used this later to guide installation of the new cap. In the picture below, the cap has been loosened and pulled away and the shield has been lifted out to expose the rotor and the three hex bolts holding it in place.

10) Unscrew the three bolts with a 3mm hex key. After removal, the distributor will look as shown below. Install a new rotor. There is a built-in alignment notch to guide the new rotor into the correct rotary position.

11) Install the shield over the rotor. It has an o-ring near the outer edge and simply fits over the rotor. Then install the new distributor cap. In the picture below you can see the standard screwdriver engaged in the slot of the bottom screw on the new distributor cap. Very poor visibility and access but it can be done!

12) Reattach the ignition wires in the correct order.

13) Reinstall the bottom half of the airbox. Reinstall the air filter. Reattach the airbox clamps.

14) Reattach the vacuum switch.

15) Reattach the flexible air intake tube.

16) Reattach the coil ignition wire to the top of the airbox.

17) Reinstall the battery.


Parts inspection: After doing the job I took a closer look at my old cap and rotor. The date of the rotor was stamped up inside the shaft… it said 96 (my car is a ‘

97 with 113K miles). I figure these are the original cap and rotor. The engine had no misfiring or ignition symptoms, but I figured it was prudent to change these parts.

Cap: Heavy build up on the five edge contacts. Some deposits on the sidewall of the cap. No cracks in the sidewall.

Rotor: some peeling and flaking of the epoxy around the edges of the tip. Some deposits on the metal.

17 Replies to “Replace Distributor Cap & Rotor Volvo 850, S70, V70”

  1. Thank you for all the wonderful help and may I ask where do you get the ratcheting hex wrench shown in the picture, as I have never saw that one before. I have several hundred pounds of different tools as well as the standard tools too but that appears to be different.

  2. It took only 20 minutes to replace cap and rotor on my 95 850 non-turbo.
    1. I removed the electrical connector going to the top of the air cleaner housing and removed the wire harness secured to the side of the housing. Swing the top of the housing out of the way.
    2. Use a 1/4″ drive ratchet with 6″ extension to remove top screws from distributor cap.
    3. I attached a 1/4″ universal to the end of the 6″ extension on the ratchet. Working blind, I used my left hand to position & hold the socket on the bottom distributor cap screw while I operated the ratchet handle, angled slightly to the right, with my right hand.
    4. I inserted a torx bit into a socket adapter and used the same technique to remove the rotor.
    5. Installation required reversing the above steps.

  3. Hi. I own an 850 in the UK. I replaced my cap some months back, but the original had a black cover over it, and the new one not. What is this difference all about and is the one with the cover on “better” in any way?

    Thx very much.

  4. Steve–
    Thanks for the great info. My 94 non-turbo 850 took only
    20 mins also. I used a 5/16″ socket on a 1/4″ ratchet with only a 4″ extension to remove the distributor screws. The rotor torx screws were no problem using the correct size folded out from the holder.
    I seemed to have quite a bit more room than pcitured above.
    Thanks again.

  5. Finding a Tool
    You should be able to find a nice tight-space ratchet anywhere. I happened to find one in Home Depot that accepts a 1/4 adapter for a socket at one and, and a screw driver bit (or your Torx bits) at the other end. I paid about $16, and I see them on-line for about $20. Just one option – I have no opinion about Husky Tools, but this worked for me. Good luck.

    Here is a link:

  6. Hey,

    Just did this swap recently. Well worth it and very satisfying.

    However! I was very tired and left the rotor shield off!!

    So dumb, but then again, is it necessary? I will do this tune up again in 20-30k miles (1.5 to 2 years) anyway.

    Do I need to go through everything again and put the shield back in??


  7. Matt – Did you say there’s no need to remove & disconnect the vacuum switch in replace the dist rotor & cap? I don’t want to do any more than I have to. Thank you.

  8. I did a tune up today (bosh platnium spark plugs, bouigord wires, bosh rotor and cap and of course a bosh ignition coil)
    I have a 98 xc70 awd.
    I used this guide but ran into some problems being there are slight differences with my vehicle. I looked on the help forums here and volvospeed and swedespeed and this was the only forum i could find outlining how to remove the air filter(cleaner) assembly. The was my main problem in doing the tune up as it blocks access to bolts and screws.

    I guess it’s pretty simple now that i did it. but at the time working in 27 degree weather on an icey driveway it was difficult. took me 2 hours to figure how to get it out of the way.The fuse box is on the backside of the assembly blocks your view and reach.

    The two pincher prongs that hold the assembly in dont need to be pushed, simply pull the assembly straight up and toward the engine as there is a prong on the wheel side(which will pop out with the rubber washer).
    Removing the vacuum switch mention in step 6 also ate lots of my time as i couldn’t find the screws. I could see the three wires coming from this piece located in the rear of the assembly. once i pulled the assembly from the prongs I had a better view of how to remove this piece which took some direct force to pull the clip from the assembly.
    Also the intake hose is attached to the bottom of the assembly jig this off before pulling the assembly out. There’s lots of shimmying in this process. just be careful.
    Sorry I didn’t take pictures but just don’t be afraid to use some gentle force, not brute force.

  9. I did my rotor and cap last weekend when I did my PCV system.

    I just have one simple comment; why go through the hassle of only removing the bottom of the air box? It takes all of 5 minutes to remove the battery, air box, and hoses that would potentially be in the way/annoying.

    I’m no mechanical genius, and the PCV was definitely the most difficult thing I’ve done on a car without assistance from an actual mechanic.

  10. Excellent tutorial. Just did my 98 V70XC tuneup, and this tutorial was a big help getting prepared for it.

    Couple of comments –

    On turbo engines, it is easy to remove the turbo to intercooler metal pipe that runs over the top of the distributor, makes it much easier to deal with the wiring and access to the No. 5 plug if you are changing it. Pipe attaches with hose clamps at each end to rubber hose sections.

    As a previous poster noted, the vacuum switch on the 98 is simply clipped onto the side of the airbox with a plastic tang, can just be pulled right up to disengage.

    I disconnected the air mass meter from the upper airbox to allow the airbox to be moved completely out of the way.

    I did not have to remove the battery, looks like that would only aid in removing and replacing the plastic air duct on the inlet to the air box, but I was able to do that easily with the battery in place and the turbo pipe out of the way.

    Recommend using a T handle 3 mm hex key, or one from a set contained in a handle on the rotor retainer screws. My long single key went flying to parts unknown when the first screw overcame breakaway torque (which was pretty high) and popped loose!

    Used an 8 mm socket on a small straight ratchet driver handle for the cap retainer screws, plenty of room to access the hidden bottom one with the airbox and turbo pipe out of the way.

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