GRoup:
My '91 240 with 177k miles will probably fail NJ emissions this month, and I would like opinions (facts would be even better) on what to change to get it to pass.
Two years ago at 145K miles it was marginal and was above the readings taken two years before that.
The NOx and HC were just under the limit two years ago.
The CO percentage is less than half the limit and has not increased much.

I hate to change the cat because the car will be for sale in a month.
Otherwise it is cherry and has no other issues.
Runs perfectly, fuel mileage remains the same, smooth idle.
It does have a vacuuum "leak" in the heat/defrost system which allows me to hear one actuator working when I accelerate. But that is only a small "leak" and not worth fixing.

Could it be the O2 sensor? That costs a lot less.
If you think it is the cat, is the one sold by FCP Groton a decent one?
Will it do any good to block off the small vacuum line at the engine to eliminate the "leak"?

Should I put in new plugs? The cap, rotor, and wires were replaced last year.
Should I give it a 20 mile high speed run on the interstate before going to inspection? Premium gas?

Who has facts?

Thanks,
S'V'

I live in NJ too (Exit 9 ha-ha-ha!!!) and in 2001, my 1987 Volvo which then had about 175K miles barely passed NJ emmissions after a complete tune-up ... the inspector gave me a dirty look, but I was happy that it passed!!! Even though my car barely passed the stringent NJ emmisions, it ran very well.

To make a long story short, I had temporarily taken my Volvo off the road, but in 2004, I decided to put it back on the road ... she fired right-up after sitting for several years in my driveway. It smoked a little, but after 15 minutes or so, it ran just like it did before I took it off the road.

Because it was now 2004, I had to have it re-inspected, so I changed the oil and did a complete tune-up. But this time around, after three attempts, I just could not get it through inspection. So now I was faced with a decision of trying either a new o2 sensor or a catalytic convertor, both of which are theorectically designed to last the "life of the vehicle," which now had about 205K miles.

I decided to replace the catalytic convertor. Immediately after replacing the convertor, I drove to the inspection station, and IT PASSED with flying colors ... the emmission levels were so low that the machine barely registered any harmful emmissions. I was extremely happy!!!

I bought the catalytic convertor off of eBay for about $100 and it bolted right on. It is an "ultrafit" brand, but I had to buy a flange gasket separately.

Just another thing I'd like to mention. When removing the old original catalytic convertor, I had to break a factory weld joint at the flange using hammer and chisel. If you do this, wear goggles and when using a hammer & chisel, be careful not to disturb the front header pipe too much (i.e., keep it from moving) as you may cause a leak at the exhaust manifold, or worse yet, you may break the flange on the header pipe. Just don't bang too hard!!!

Good Luck!!!

AlexB

I've used a CRC product - sold by NAPA and others - called "Guaranteed to Pass" Emission Test Formula. It's a fuel treatment. I'm not familiar with all of the consequences of utilizing this kind of chemical; however, the car (non-brick) had failed poorly several times (after a complete basic tune-up), yet after running one tank of gas with the CRC -- it passed with flying colours. The improvement in each of the three measures was striking and remarkable. Also, put in high octane Chevron Techron (good gas for low emissions) and ran the car for a good 30-40 minutes to heat up the cat prior to the test.
--
dnvolvo '89 765T - '91 245

SV;

Check out this post from a car I considered for purchase. RWD - Emissions results from '87 745--HC/CO relation You'll note the corresponding high HC and high CO. What is happening is the HC (unburnt fuel) is now free to join with oxygen (carbon + oxygen = CO).

- Oil change prior to testing will help with HC.
- An inoperative O2 sensor will give you high HC and therefore high CO.
- Bad Cat or inoperative EGR valve (not sure if your car has one) will give you high NOx.
- overly-advanced timing will raise combustion temps and oxidize nitrogen (NOx).

Ensure car is fully warmed up prior to test (cat works properly) and use the highest octane gas you can (helps with NOx).

BTW you can have the O2 sensor and cat checked out. I believe the cat should show a temp differential (dT) of 25-40F. If there's no difference in temp from input/output, it's likely not working.

--
Norm Cook Vancouver BC; 1989 745T 204,000KM

If you do fail... Take your brick to Larry's Garage in Long Valley (It's in Hunterdon County or just outside). He has been taking care of my 85 240DL Wagon since I was 7 (I'm almost 19 now). He has also been taking care of my Mom's 98 V70 XC. He is cheaper than any dealer by far and is Volvo Factory Certified. He will also do the inspection for you as he is one of those private places that do inspections, very convenient. I failed inspection last year and he got the car fixed and inspected for under 50 bucks. The only problem that you may run into is getting an appointment, he is always busy.

When was the last time the O2 was changed? Definetly fix the vacuum leak. New plugs will also help you if you're borderline close. Clean the flame trap if you haven't in awhile.

My 82 passed NJ inspection last year with flying colors. I replaced the Cat ($100) and fixed some vacuum leaks. If you sell the car in NJ and have a fresh inspection sticker, you can use the fact that it is good for two more years to increase it's sales value. Good luck.

Mario
--
'I've always been crazy, but it's kept me from going insane' Waylon Jennings

Mario:
Where did you get a cat for $100?
Changing the O2 sensor could cost that much.
-- S'V'

Try this link:

http://www.all-catalytic-converters.com/volvo-240-converter.html

Hope that helps.

Mario
--
'I've always been crazy, but it's kept me from going insane' Waylon Jennings

How about selling it out of state on ebay or autotrader. Here in Ohio, there are only a few counties that require an emissions test.

Regarding the Cat., I replaced mine at a shop who did a custom cut and weld for a very reasonable price.

Gary