I just purchased a 1997 850 wagon. Non turbo (BTW which engine do I have?)
Cleaned up everything including under the hood. (Pressure washed....not so good an idea)
Volvo has 167,000 miles on her.
And has just started hesitating when I step on the pedal.
This only occurs in first gear before it shifts.
I'm going to replace the plugs, But before I start replacing other parts I
thought someone may have an idea...

 

Sounds like moisture in the ignition system from the pressure washing.

 

Check your spark plug holes, make sure there isn't any water....check cap and rotor....

 

Greetings from Chicagoland.


Sorry to hear about the hesitation.

Does the Volvo have maintenance record? If not, it is not a bad idea to replace/inspect the following items and they are not that expensive:

1. Spark Plugs (I would use either genuine Volvo or Bosch platinum/iridium, I am using Bosch twin platinum and am happy with them)
2. Distributor Cap & Rotor
3. Air Filter
4. Fuel Filter
5. Clean the throttle body with carburetor cleaner that is safe for O2 sensor & catalytic converter.
6. Check for vacuum lines (plastic elbows)
7. Put a bottle of injector cleaner in the fuel tank (Techron seems to be good, but I used Prestone and didn't feel much difference)
8. Put a bottle of water remover (isopropyl alcohol) in the fuel tank (don't mix with injector cleaner)
9. Check the PCV system

I believe your engine is either B5252S(2.4L 10-valve) or B5254S (2.4L 20-valve)

Good luck,


JPN

 

Does it still do it a day or two after? if not don't worry about the moisture is probably gone, but if you want you can pull the plug wires and distributor cap and clean it all up, taking notice to the contact points in the distributor cap and the contact on the Rotor.

-Mike

 

Thanks for the tips guys. The hesitation went away after I replaced the plugs (Bosch). The previous owner had
his local dealership work on his car, so I think it was maintained well (except for the dog hair!). I'll add injector
cleaner into the tank, and perform routine maintenace. There were no codes on the computer, after I cleared
the miss firing cylinders (1,2,3,5). I don't know when the last time he replaced the rotor and cap, but I don't see
any cracks on the outside. Oh one more thing, the brakes are terrible. I believe that the rotors are warped. I looked
up the procedure for replacing pads/rotors in the book (provided by the previous owner). Do the rear brakes have
disc's as well as drum brakes? I was a little confused by the emergency brake/ cable hook up.

 

If I am not mistaken, the emergency brake on the 850 is actually another set of pads that apply pressure to the inside of the brake disc. It is like having drum brakes on the inside of the hub/disc as your emergency brake. The regular pads on the outside of the disc are what constitutes the rear brakes that are activated with the fronts when you press the brake pedal. In the event of brake failure, the handbrake actuates the pads that apply pressure to the inside of the hub/disc in a drum type setup.

Hope that helps,
Rob

 

Rob's correct. Doing rotors/pads are easy on this type of setup, just remember to not have the parking brake engaged when trying to remove the rear rotors I did this on my BMW about 10 years back and was hammering away on the rotor. Once I released it, it came off easily by hand - AB

 

a cracked distributor cap is not the only sign of a bad part, there are 6 electrical contacts inside the cap, (this is how power is distributed to plugs, hence the name haha) you may want to pull of the cap and check the electrical contacts, same goes for the 2 contacts on the rotor. yYou can clean these up with a little steel wool, make sure it's clean and dry when you put it back together. This is a fairly easy process and does not take taht much time, give it a shot.

The Brakes are fairly easy to replace as well, just make sure you clean up the calipers and sliders well, you should use lube on the sliding areas of the caliper. try some CV joint grease on the parts but make sure you don'r get any on the pad material.

The Rear brakes have a mini little drum inside what was mentioned earlier. It is possible that the rear rotors may not come off due to a tight E-Brake. there is an odd hole in the rotor and that is used for adjusting the Ebrake. with a flash light turn the hole towards the top and look through the hole and you'll see a little star or gear looking thingy, it is that part you may have to turn(witah a 1/4" flat screwdriver) to release tension on e brake shoes.

I picked up 4 rotors and F + R pads from a ebay seller, I paid $232CAD for all of it, mind you the seller was somewhat local so i drove to Toronto to pick them up. even with shipping it could be a deal, check it out.

-Mike

my ebay rotors and ceramic pads which io paid extra for(lower amount of brake dust on alloys)

 

Hello Mr. jtvrba,

Greetings from unusually warm Chicagoland.

Glad to hear the hesitation is gone. You might also want to check the inside of the distributor cap, as well as rotor tip. These two items are often neglected. If the rotor tip and cap electrodes are pitted/burned/carbon-tracked, you might want to put new ones in. Even OEM parts (Bosch) are not that expensive. I usually mark the cap position with correction fluid before removal. Ignition wires are also often neglected, but you can check their conditions if you have digital multimeter & a service manual.

Mr. Robrike and Mr. B1mmer have stated pretty much all about the rear parking brakes. Yes, there are brake shoes inside the discs, just like drum brakes. The shoes are probably good, as they are only used as parking brake. Just spray-clean with brake cleaner.

850 brakes are straightforward to work on. As for the fronts, they are typical floating-type caliper. You will need new caliper bracket bolts (I bought them from FCP Groton). You will also need a torque wrench, if there is an Autozone near you, you can rent one for free (you pay, but as long as you return it within 30 days, they give your money back). As for the caliper slider pin, you'll need a 3/8" drive socket-type hex wrench. Follow the procedures in a service manual, take them apart, clean them good with brake cleaner. Scrape/sand off corrosion. Make sure to put anti-squeal compound everywhere EXCEPT the friction surfaces. Silicone-based brake grease seems to work well, but I used cv-joint grease and it worked as well. Put brake grease on the slider pin as well. Putting the springy-thing (pad holder) may be challenging, but keep trying and they'll go back in their nests.

As for the rear, buy hardware kit before you disassemble. The pads are held by spring + pins, and when I did mine the pins were severely corroded and fell apart as I removed them. You will need a pin-punch & a hammer to remove the pins. Also, a large vise-grip (locking pliers) or a large C-clamp is necessary to push the piston back in so you get enough gap to put the new pads in. Make sure to buy a new set of pad shims & new caliper bolts.

As for the pads & rotors, try to go with OEM parts. Cheap parts tend to squeal more and may not provide sufficient performance. I used Brembo rotors & Textar pads (Roulands-Dan Block for the rear pads), and so far I'm happy with them. But shop around, you may be able to buy cross-drilled discs at a reasonable price somewhere.

If I were you, I would also replace the brake fluid (this one is neglected way too often). If you're not sure about the procedure, a dealer or generic garage should be able to do it. I bought a one-person brake bleeder from FCP Groton (Motive Products, $50, made in USA!) and had some fun bleeding the brake fluid.

When you're done, make sure to test the brakes as a general rule of thumb. Safety first!

Good luck,


JPN

 

Thank everyone,
JPN - I found another forum/web site for the brake replacement procedure Bay 13... pic's and all.

MikeySq - I'll replace the cap and rotor, for the cost of the parts it's worth the peace of mind.
Now job on your brake job by the way.

I've been a little busy with the car now that I have an oil leak coming form the engine/tranny area. (bottom of engine)
I'm hoping this is not a rear seal...I've heard this can be an extensive repair.....

 

Man, you are not kidding about expensive on the rear seal repair. I had a quote of $1250.00 from my local dealer. I called a transmission shop that did some good work for me before on a Ford Explorer and they only wanted $550. When the rms bit it on a 740 turbo I used to have I had a tranny shop do it and it was $200.00 even. They are used to pulling the transmission and considering it is just remove and reinstall they usually don't charge much. It would be worth calling a few places that deal in transmission repair to check their prices. Mine is leaking now about 1 quart per 150 miles so it is getting replaced. I would get the pvc system in order before replacing the seal so you don't blow another.
Best of luck to you, I feel your pain.
Rob
97 850