Help! My '86 Volvo won't pass smog test!

I just had my 1986 740 wagon smog tested (California) after receiving a
notice to have it tested at a "test-only" center. I think I read on one of the
forms related to the notice that this make/model is designated by the state as
having a "High Emissions Profile" and I assume that's why the test had to be
performed at a test-only center.

Unfortunately the car, which I'd just had repaired (something very minor) by
a Volvo specialist just before the test, and which my mechanic said was in
suprisingly good mechanical condition, failed the test.

At my mechanic's suggestion I then had the oil changed and a "3-step" fuel
injection service done (not by the mechanic mentioned above but elsewhere as
he'd recommended, so he had no financial incentive for recommending it) andthen
drive it 50-60 miles to see if that would improve the car's performance on a
re-test.

Again, however, the car failed and is deemed a "gross polluter," which means
I have a couple of months more to get it serviced somehow so that it can pass
the next smog test or else . . . I won't be able to register/drive the car in
California any more!

As I write this I'm looking at the results printout of the 2nd test and here
are the results:

at 15 mph:
CO2 % as measured: 14.11
O2 % as measured: 0.48
HC (PPM): 113 (maximum is 133)
CO %: 0.73 as measured (maximum is 0.82)
NO (PPM): 1794 as measured (maximum is 1125)
RESULTS: FAIL

at 25 mph:
CO2 %: 12.96 as measured
O2 %: 1.55 as measured
HC (PPM): 183 as measured (108 is maximum)
CO %: 1.02 (0.62 is maximum)
NO (PPM): 2005 (maximum is 955)
RESULTS: GROSS POLLUTER

As can bee seen from the above, a big area in which the car is failing is in
NO, which at 25 mph is actually double of the maximum allowed.

I would love to hear from anyone who's familiar with ways to get old cars
such as my 1986 Volvo to the point where they can pass stringent smog tests.

 

| I just had my 1986 740 wagon smog tested (California) after receiving a
| notice to have it tested at a "test-only" center. I think I read on one of
the
| forms related to the notice that this make/model is designated by the state
as
| having a "High Emissions Profile" and I assume that's why the test had to be
| performed at a test-only center.
|
| Unfortunately the car, which I'd just had repaired (something very minor)
by
| a Volvo specialist just before the test, and which my mechanic said was in
| suprisingly good mechanical condition, failed the test.
|
| At my mechanic's suggestion I then had the oil changed and a "3-step" fuel
| injection service done (not by the mechanic mentioned above but elsewhere as
| he'd recommended, so he had no financial incentive for recommending it)
andthen
| drive it 50-60 miles to see if that would improve the car's performance on a
| re-test.
|
| Again, however, the car failed and is deemed a "gross polluter," which
means
| I have a couple of months more to get it serviced somehow so that it can
pass
| the next smog test or else . . . I won't be able to register/drive the car
in
| California any more!
|
| As I write this I'm looking at the results printout of the 2nd test and
here
| are the results:
|
| at 15 mph:
| CO2 % as measured: 14.11
| O2 % as measured: 0.48
| HC (PPM): 113 (maximum is 133)
| CO %: 0.73 as measured (maximum is 0.82)
| NO (PPM): 1794 as measured (maximum is 1125)
| RESULTS: FAIL
|
| at 25 mph:
| CO2 %: 12.96 as measured
| O2 %: 1.55 as measured
| HC (PPM): 183 as measured (108 is maximum)
| CO %: 1.02 (0.62 is maximum)
| NO (PPM): 2005 (maximum is 955)
| RESULTS: GROSS POLLUTER
|
| As can bee seen from the above, a big area in which the car is failing is
in
| NO, which at 25 mph is actually double of the maximum allowed.
|
| I would love to hear from anyone who's familiar with ways to get old cars
| such as my 1986 Volvo to the point where they can pass stringent smog tests.
|

This is amazingly similar to a posting by "||Sergio||.

 

tests.


Something is very wrong, my mom's '86 with a gutted catalytic converter got
something like 23 ppm HC, and significantly below all your other numbers as
well. How's the idle? First thing I would do is check for vacuum leaks, then
pull the injectors and make sure the path is clear and that the plastic cap
hasn't cracked and broken off the end of any of them. I've seen both cause
an emissions failure, on one the intake gasket was tweaked and was partially
blocking one injector and on the other the plastic cap broke off so it was
just pissing fuel into the cylinder. Both idled very slightly rough but not
as bad as one would think for how bad the emissions ended up.

 

Does this model have an EGR valve?
If it does change it.

 

I'm fairly certain it doesn't, don't think I've ever come across a Volvo
that did.

 

I always found new injector seals really helped in passing smog. You can tell
if you need them by spraying a mister bottle of water near the injectors. If
the engine stumbles, its sucking in the water vapor through worn seals. When
you put in the new seals it won't stumble any more from this test.