For the '95 turbo 850, at what rpm's should it start making boost?

I ask cause the specs I found for the TRQ said that it makes 220 torque at just over 2000 rpms.

My wagon (which does seem to have been neglected by previous owners) doenst make boost until over 3000 rpms.

I will be installing a boost gauge ASAP, and that may help me get a better idea how well the turbo is working, whether or not its even making full boost and when it really comes on.

I had originally hoped I could up the HP on this volvo. But after seeing the prices for things like ECU mapping and turbo back exhausts systems I have decided the best I can afford is to get the whole system working as close to original as possible.

I found an 02 sensor on ebay that was much cheaper than others, tho both say they work for my model.
I dont have $$$ to replace a sensor that costs over $100 if it may be working fine. But if I can get the sensor for $40 then I dont mind replacing it just cause its old and may help the motor run better.
see link: BMW Mercedes Benz Volvo Universal Oxygen Sensor O2 4 Wires NTK Japan New 29400 | eBay

Also, do you guys reccomend any fuel/engine additives?

I have already replace wires/cap/rotor and plugs.
What other "low cost" parts should I consider replacing? parts that tend to wear out and eat away at power and fuel milage.

I am trying to search for these answers before posting, on some Q's I cant find anything and on others I find too much info to sort threw!

 

The best thing to do is read the sticky's. They have a world of info for you.

When you did your plugs, did you go OEM or some other plugs?

A car will boost as soon as you put your foot in it. Maybe have a little turbo boost, like a second or two. You should have a boost gauge in your car, just above the fuel gauge. When the needle is at 12 O'clock you are entering boost. Boost and torque are two different things, I doubt your car sees 220 FT LB of torque at 2000 rpm's, probably more like 4,000 rpm's. Here is a link on iPd's website that talks about turbo boost:
Tech Tip #10079 - Understanding Turbo Boost

It is possible that your turbo is not boosting properly. There are several reasons it may be weak, it will take some trouble shooting to figure that out. From a worn turbo to vacuum leaks, several things can effect it.

As for O2 sensors, DO NOT install a universal sensor in these 850's. They do not work well with the system. Your best bet is to get one from a junk yard. There are plenty of cars there with 2 year old 02 sensors in them. I have gotten a few from junk yards from $10 to $25 that worked well.

 

Ok, Ill look into the junk yard o2 sensors.

I had a feeling the universal o2 sensors were not a good idea.

I installed E3 diamond fire plugs. Those are supposed to be pretty good.

making peak torque at 4000rpms sounds right. thats where the car really pulls hard.

the boost gauge hits 12 o'clock at about 2500 rpms i think (hard to watch the gauge while flooring it)

I have been reading threw the stickys. Im almost on info overload...lol.

I bought a haynes repair manual last night off ebay. That should help me figure out whats what under the hood.

I may buy a OBD II reader. advance auto parts has one for $100 that seems like it can do alot (even real time readout) clear codes ect.

The car has some kick to it, just at a higher RPM than I had expected. But my only turbo car before this was a '92 740 turbo wagon...which was a different beast.

 

If you think your experiencing turbo lag you can adjust the wastgate actuator rod, it would be underneath the heat shield on your turbo just take the cotter pin out of the arm stud then loosen the lock nut on the rod now you can tighten the rod head. You can do 3 to even 6 turns I would start at about 4. This will allow the turbo to hold your peak boost longer and help a little with lag you'll notice a difference. Then if you want you can a manual boost controller only around 30- 100$ I went with a turbo logic mbc off of boost controller.com only $60 and it came with 4ft of vaccum hose and cap off pieces works great. But be sure to get the boost gauge first you can get an autometer gauge for around 40 at most auto parts stores and they usally have cheap a pillar pods for around 20 hope this helps if you want some more power for cheap.... I would make sure the car has full tune up and is running good before adding to much boost you can usally boost around 14 psi safely just don't floor till its around 2800-3000 rpm to be on safe side... You'll like 14lbs. For a while hope this helps!!

 

Because of your experience I would not go making changes to the car until you get to know your car a bit better. Simple changes like adjusting your wastegate rod can lead to overboosting and fuel cut off. There is more to just changing things, you need to understand what your doing and how to protect your investment. I recommend reading and learning first.

side note, the 220 at 2k is not accurate information

 

yeh, im not ready to add any performance. Im still working on getting it upto spec.

I dont really understand how adjusting the wastegate changes when the turbo STARTS making boost.

I thought the function of a wastegate is to allow excess boost pressure bleed off.


There are a few other little areas I am making progress on.
The rear driver window was stuck 1 inch from the top. neither window switch would work. I just pulled the door panel off and got the window to go all the way up.

Then the floor door in the back wouldnt lock...so it bounced and made noice any time I hit a bump. Got that unstuck so I can lock the floor.

I also have to replace the wagon door support struts as the door doesnt stay up. Will be ordering a replacement soon. Doesnt look to hard to replace. Im assuming the panels on the headliner when removed will allow access to the struts.

When I recieve the repair manual I bought I should be able to figure out more stuff on my own. When I can look at a pic with arrows showing what is what then Im pretty good at figuring out how stuff works and how to repair it.

When temps warm up, I think I will replace the trans fluid (not a full flush)
I need volvo spec trans fluid right?

 

Tranny: https://volvoforums.com/forum/volvo-...tep-step-5157/

Code reader and more: www.ScanGauge.com

 

Thanx, the link spells it out pretty clearly!

I got a OBD II reader off ebay for $65. Says it can read (with definition) and clear codes as well as give some real time readouts.

I also need to get this car into the shop for an oil change, who knows when the last owner did it.