850 turbo 96: emissions failed: hi HC & CO, + O2 error codes

[hanseich]

Hello everyone,

thanks everyone for helping me to figure out how to fix the exhaust . I had a local shop weld the muffler onto my 850. Now, the exhaust has no more leaks, but it ended up failing the emissions test (Ontario, Canada). I'm currently reading up on everything, but there are so many variables. Here are the facts:

850 turbo, 96, 190 000 km (118 000 miles)
Emissionstest (ASM2525) at 1639 RPM (Dilution 15.8 )
HC ppm Limit 58, Reading: 85, FAIL
CO% Limit 0.32, Reading: 0.66, FAIL
NO ppm, Limit 435, Reading 49, PASS
Test passed at idle (856 RPM).

I also have two error codes:
P0133: O2 Sensor Slow Response, Bank 1, Sensor 1
P0137: 02 Sensor Low Voltage, Bank 1, Sensor 2

Also, I've looked for signs that the PCV does not work correctly (smoke out of oil dipstick tube), which is not the case, but there is oil leaking out of the oil filler cap, some out of the dipstick tube and some in the rear of the motor block (leak not found yet, a mechanic has said, it does not look like RMS, as there is oil even far above the RMS).

Actions taken so far:
Fuel cap was changed before test, because it was not working correctly.
I refueled with high octane gas (91) after the test, as the fuel in the tank was low octane (not recommended for 850 turbo)

So I've not really taken action so far as I'm not wanting to randomly tap in the dark.

What I think so far is:
Change spark plugs (I'm not sure when they were last checked, because I just purchased this car), clean contacts on ignition cables and rotor (air filter was changed not too long ago, and I don't think this would be cause for a failed e-test.

I'm interpreting high HC as un-combusted fuel (hence a good tune up might fix it), and high CO% as too much fuel is being fed into the engine (not sure what this is cause by, a faulty sensor?).

What else should I do? The muffler guy (at Midas), that changed the muffler, said that he doesn't think the catalytic converter is broken, as the original ones should last very long. I'm trying to avoid changing expensive parts (ie: cat converter, sensors) only to find out that it does not fix the problem.

[precopster]

I'm going to stick my neck out here and endorse a product, which I usually don't do. Five years ago I trialled a friction modifying product in my 740 turbo made by this company and it worked really well. Unfortunely I blew the head gasket shortly after and then had extended periods of time working on project cars.

I had used this network marketing company's health products with great success and everything they promised had been delivered as I had overcome a serious bowel disorder.

After another year this company released a revised product range with not only a metal friction modifying product but also a fuel system treatment and pre-oilchange engine flush. I went to a couple of product demos, bought the system for my newer 960 and trialled it for one fill and tested a 27% decrease in fuel consumption but the oil burning remained. The fuel benefits then decreased to around 15% on the next fill then settled at around 8%. It was paying for itself (the 3 part system cost was around $85 and was meant to be redone at the next oil change interval) Then my accessory belt wrapped around the crank and presto I had 24 bent valves. During the rebuild time I lost interest in the product (though I saw afew more product demos and heard afew testimonials from local area users)

After discovering my cylinder bores in the 960 had serious ridges during the cylinder head replacement (it was a used block with unknown mileage) and serious blow-by from the dipstick even after a PCV change I realised this product wouldn't be effective to seal the bore as it was too worn. I didn't use it again. I continued to study the documents and hear testimonials then I discontinued going to the meetings as my health had returned and was being maintained by the products.

Some of the benefits claimed were substantially reduced hydrocarbon emissions as well as reduced NO (nitrous oxide) emissions as well as the friction losses (power gains) and reduced fuel consumption. The decreases in emissions were attributed partly to the crankcase cleaning that the oil flush can perform by removing some of the suspended sludge on the crankcase walls thereby disallowing this sludge to be reheated and give off noxious fumes. The other benefit was that the fuel system cleaner could safely remove deposits from the fuel tank (which apparently further add to emissions) and hold them in a burnable suspended state until they were passed out of the injectors for combustion.

The whole thing was almost forgotten by me until recently when I Googled Neways Roil Platinum. Forum after forum was filled with reports of greater power or, depending how the throttle is used, greater economy. Many of the forums were filled with users reporting lower emissions and being able to pass testing easily. Also compression restoration by means of sealing surface imperfections in the cylinder bores. So the prophecy was fulfilled and now Neways Roil stands as not only a great product for the home user, but also as a great motorsport protector. Winning teams of drag racers here in Australia now swear by it. The current land speed record title holder also uses it. It's a product designed and manufactured in the USA and I believe all the claims now and then some.

In your particular case yank the battery cable and then press the brake pedal. This will reset the ECU adaptives to baseline and allow settings to reset. Then go and find yourself some Roil.

[hanseich]

Does anyone second the answer of precopster? I see, you are very involved in the forum, so I'm going to take your answer seriously. I'm looking for the conventional solution to this problem though. I'm not really willing to just reset the ECU and use Roil (is that even available in Canada?) and hope the car will pass the emissions test. I'm pretty sure there are some pretty bullet proof ways to change the engines emissions as Volvo intended it. Then on top of it I'll try the Roil.

[kcodyjr]

Clearly it's running rich. If it was ignition, you'd have crappy enough performance under load to be complaining about that, and that wouldn't explain the O2 sensor codes.

If the front one is bad, often the rear one also reads bad even if it isn't; but in your case, I suspect both are shot.

If money is tight, start with the front one, if you can afford it, just do 'em both. And yes, reset the adaptives afterward.

[precopster]

You won't find a single solitary person to back me up on this forum I'm in virgin territory here. But as I understand it, cars' engines are not too disimilar and respond the same way. Volvo never intended for our crankcases to be gummed up with years of sludge. This 3 part system can clean the crankcase & fuel system and then friction modify the metals so less throttle is used for a desired output. Emissions are naturally lower.

It's the first time I mentioned it with a full explanation.

Do your own research. As I understand it emissions testing takes considerable time and expense by being away from your employment. I've seen afew guys make some changes and pass through and quite afew others give up and sell the car.

Have your O2 sensors replaced if needed. Also how's the PCV?

Canada Neways can provide you with distributor details for purchase. http://www.neways.com/ca-en-ca/content1.aspx?pageid=113

[hanseich]

precopster, after accidently finding this video:



of someone shoveling out the sludge out of a badly taken care car, I'll give the Roil a try. I never knew that sludge could build up like that. So far the work is coming along well on the old 96 850 turbo, and it would be nice to keep it and maybe undo some of the bause of the previous owners (although I think he took pretty well care of it, with regular oil changes)

[rmmagow]

I have had good luck with a Lucas product added to the gas and run the car a lot on the highway. I had similar emmissions test results, close but not good enough. After the Lucas stuff, two tanks worth, and a bit of 70~80 MPH for a couple of weeks the retest passed.
this was on a non-obdII car, but one that uses an O2 sensor. There was an article here, maybe on the Fast Friday thing about running the engine with an intentional vacuum leak to force lean to burn off O2 sensor deposits. You can sometimes remove an O2 sensor and hit it with a propane torch to burn off carbon and get it working again.
The Roil treatment certainly sounds good! I've not heard of it before this but it sure is worth looking into. Don't be cautious about resetting the ECU after making changes, it really the only way to get the car to re-learn properly. I did plugs, cap, rotor and wires on my 98 V70 and a lot of evils went away.

[precopster]

I wonder if there is a place where you can hire a gas analyser. Perhaps you should look into the possibility of this. If you can have it over the weekend each time you make changes you can retest.

[precopster]

precopster, after accidently finding this video: of someone shoveling out the sludge out of a badly taken care car, I'll give the Roil a try. I never knew that sludge could build up like that. So far the work is coming along well on the old 96 850 turbo, and it would be nice to keep it and maybe undo some of the bause of the previous owners (although I think he took pretty well care of it, with regular oil changes)

I'd seen that video recently and I had placed it in my favourites. After seeing it again it's clearly visible how much sludge can form. I think non-synthetic oils generally leave more sludge so after high mileage there's a pretty good chance most cars have this.
One thing I was aware of when I used Roil with my 960 is that the Neways Engine Flush made my oil come out almost pure black, even though the liquid poured in was almost clear and my oil was quite clean.

[hanseich]

I ended up ordering two new O2 sensors from FCP (still waiting for it, I can't tell you how often I check for the package to arrive ), replaced the spark plugs (NGK, inherited from the previous owner) cleaned out the distributor cap and rotor (polished the contacts). Those will have to exchanged for new ones, but for now, they will still do. The retest is going to cost $17 and I'm pretty sure with the proper high octane gasoline (and an ECU reset) the test will run fine.

I'll let you know once the O2 sensors are in and the retest is done. If it fails, I'll be back to "drawing board".