Volvo 850 - Popular Questions, Answers, Tips & Manuals

Try a can of Lucas Transmission Slip - 100M - see if that helps. Something is sticking in there. This might free it up.

Have you diagnosed the problem to be the head gasket, or are you guessing.

What are the symptoms.

I would be carrying out a compression check, and cylinder leakage test on all cylinders.

If it is a blown head gasket, it will need replacement, don't bother with any dodgy chemical sealer, it will not work.

Probably not. There are often vacant positions in fuseboxes, relay boxes and the various other locations electrical and electronic equipment is sited.. If you need to locate the ABS ECU you need to discover the official location, which could be almost anywhere - behind the dash or behind kick panels, behind the glovebox...

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Normally the ac shouldnt be starting when you turn on the vehicle. This shows that there is a faulty ac switch. You need to check the ac switch and then followed by the ac thermostat.

Sounds like its in limp mode, where the transmission has a problem and to protect the vehicle it will not go faster. Check online for the parts you need, its mostly a solenoid that fails, unless you blew 3rd gear or something.

If you don't believe the shop take it to another one. If they tell you the same thing then you have your answer. The cable could just need sprayed with some silicone or has worn thrue its jacket.

Blown head gasket, cracked block. check for milky color of oil.

Hi, chk ur rear transmission mount.

Could be rear brake locking up,cars arent used to going backwards or hand brake sticking on . Would look there first.

Yes, if the pcv valve is clogged or not properly connected to the air inlet, it can allow more blowby. However, if there a lot of miles on the engine, it might be time for new piston rings. Run a compression test on all cylinders.

Outside of the oil filter, there aren't a lot of places oil can exit the engine under normal circumstances, but my wife's '96 850 had a similar problem. The source of the leak in her case was the dipstick tube. We'd had the transmission replaced a few months before, and as it turns out, they had to pull the engine and transmission as a unit in order to get the tranny out. (They Hayes manual says to drop the subframe beneath the car, but given a full auto shop, it was probably just as easy for them to just pull the entire assembly.) Anyway, in the process I assume they disconnected the dipstick to give themselves more room to work. From the looks of the o-ring between the block and the dipstick tube, it appears it got deformed when being reinstalled so it failed to seal correctly, letting the oil leak out of it. Between the action of the cooling fans on the radiator and wind coming through the grille while driving, it was throwing the oil all over the place, making it hard to determine exactly where it was coming from. I ended up wiping down the entire bottom of the engine, driving the car and looking for oil. Repeat several times until I finally isolated it to the dipstick. You can buy just the o-ring online for just a few bucks. That solved the majority of the issue for me, but then I found oil leaking out of the top of the dipstick as well! There's another o-ring there, but they don't sell those by themselves; you have to either buy the whole dipstick (without the tube) to get it, or take the old one to an auto parts store and try to match up the existing o-ring to something they have in stock. I found one that was close enough, and that seems to have put to bed my engine leaks. Of course, I don't imagine you've had your engine pulled, but since your car is almost of legal drinking age, it's entirely possible the seal has simply failed due to age. Definitely recommend replacing both the top and bottom seals. There's only one bolt holding the dipstick in place, so it's not hard to swap out the one between the tube and the block.

Having a failure while driving past the same spot leads me to believe your experiencing electromagnetic interference (EMI) also called radio-frequency interference (RFI) when in the radio frequency spectrum. Find more info here: Electromagnetic interference EMI or RFI interference typically emanates from intended transmissions, such as radio and TV stations or mobile phones. Automobile ignition systems also generate changing electrical currents and voltages that can cause EMI.. Broadband EMI or RFI interference is unintentional radiation from sources such as electrical power transmission lines. With that said, your ignition module may be adversely affected by an outside source. Ask you mechanic if he can shield your module to see if that solves your problem. The ignition module is located in the front seating area, passenger side, under dash, mounted above kick panel.PS: What happens if you drive in a different direction for 10 minutes...does the failure still happen?

any check engine lights/codes?, maybe that oil sprayed onto a connector somewhere and caused an issue, most the time the connectors are sealed but if one was broken or old and cracked it could let oil in between the contacts and cause an issue. im not going to tell you its a cam or crank sensor with knowing for sure you are the one that needs to do that diagnostic, sorry.. anyways that's an intricate problem for sure and many things need to be checked before condemning one part or another. i have seen coils fried from excessive cranking under no start conditions, they can be ohmed out to see if they are bad, disconnect them and remove them from the car and ohm them out with a digital meter and compare it to spec, ohm out the primary and secondary windings . the crank sensor most likely gets a signal from a reluctor wheel which is a piece of metal behind the crank with pieces cut out of it, clean it off and make sure the crank sensor face is clean too. i would go in that order, dont condemn a part just because you think its bad. next with the main relay it can be checked or "jumped" but i dont want to suggest how because it could fry something electrical if done improperly, about the best advice i could give with the main relay is try to get it out smell it to see if you smell any burnt smells, and last open it up and check solder joints for cracks with a magnifying glass. if you see any cracks have someone thats good with a soldering iron fill the cracks and go from there. good luck and any feedback will help in your journey to fix this thing. dont get discouraged and once again if it has a code start there, even if its a history code or pending

Sometimes the electronic control module goes to sleep. Usually happens when you always unlock the car with the remote. Trying locking and unlocking the driver door several time to see if it clears up.

not something you should try on your own. Needs to be done by a place that knows what they doing and guarentees their work

check the battery voltage with a digital meter, clean the cables and terminals replace any loose ones. check grounds car off should be minimum or 12.5 anything less its probably a bad or low charged battery, with the car running with ac on and lights on high beams should be 13.5-15v anything less the alternator should be checked and or replaced. 13.5 is on the low side of the scale keep that in mind. as far as the accessories acting up, a low battery or bad alternator will cause all sorts of things to flicker and act up so start with the above first and good luck if after all thats completed and your still over time having a dead battery you have a parasitic drain, every car has a small one normally but a big one can be big trouble, disconnect the battery get yourself a test light. clamp one end of the test light to the positve cable (unhooked from battery) and touch the end of the test light to the + on the battery. if it lights up bright you have a parasitic drain. (something staying on,) unplug fueses until the light turns off and that fuse that was pulled right before the light went off is the circuit that's bad and needs to be checked. could be as simple as a light staying on or a aftermarket radio, but it can get as indepth as full electrical diagnostics

Fuel injection Relay! These things fail more when it is warm out (during the summer etc). It is a large relay located under the hood inside the fuse box. It is about the size of 2 relays put together. It is either red or green. When it gets hot out, the relay swells up an separates and causes the car to stall out intermittently.

I agree. Find a transmission. There is really no easy fix. Sorry.

Fuel injection relay. It is located under the hood inside the fuse box. It is either red or green in color. It is one of the larger relays. This is classic symptom of these things going bad. The heat causes the relay to swell and not engage properly. They die out every couple of years. Usually the car will start again after it cools down.