Failed Emissions On A Truly Grand Scale...

[LuvNLife]

Once again, you have a n00b on the site. I have done quite a bit of reading via searches, but didn't find a post that quite fit.

I've had a couple of late SN95's, and understood those pretty well, but I'm all new to the Fox world. A week ago I picked up a bone stock '89 5.0 auto LX hatch for a pretty fair price. It's showing 100K on the odometer, and I believe that's accurate. I took it in this past Saturday morning for emissions and mechanical inspections, and got the good news/bad news thing: Mechanically, it was A-OK. Emissions? Holy cow did it fail. Here's the numbers they gave me:

At 15 mph, RPM 1272:

HC ppm - Limit 55, Reading 242

CO% - Limit 0.22, Reading 0.57

NO ppm - Limit 720, Reading 1973

At 25 mph, RPM 979:

HC ppm - Limit 100, Reading 263

CO% - Limit 0.32, Reading 0.80

NO ppm - Limit 700, Reading 2200

The car, at least visually, is bone stock except for a Flowmaster cat-back, an electric fan, Accel coil, FRPP blue wires (appear new) and a generic looking CAI with exposed conical filter. All of the smog gear, from canister to pump to cats is in place. So far as driveability, on the road the car runs pretty darned well - very responsive to the gas pedal, with a lot of pickup. I've never gotten on it more than half pedal, so pushing it is unknown what would happen. On cold startup, there is no real choke or fast idle; it just starts and idles a bit rough at around 800 RPM. Warmed up, it idles about 800-850 in gear. Any time I pull to a light or even slow way down, I get a heavy smell of exhaust in the car, like it's running massively rich, but no visual smoke of any kind, black, blue or white. The oil (synthetic) only has about 400 miles/2 months on it. There is a slight exhaust leak I believe on the passenger side, probably at the header/H joint, but you can only hear it under heavy load, such as when it goes into OD at about 45 mph on a slight incline. Other than that, no strange noises at all from the engine. The electric fan is always on, as in it comes on with the key and stays on until I turn the car off. If the factory temp gauge can be believed at all, the thing runs incredibly cool, about 170/175 all the time. The voltmeter drops down to about 9/10 at stop lights, so I'm guessing the pullies have been swapped out at some time. I don't know if it's normal, but I can hear the electric fuel pump kick on with the key also. The previous owner had been running 93 octane in it, so I've been working to burn that all out, and replace it with 87.

I am going to take it into a Mustang specialty shop next week, but I'd really appreciate any input just so I can learn a bit about the possible causes. I've never been a big fan of simply throwing money at a problem until you may or may not fix it.

Thanks for any ideas you may have,

Jerry

 

[vristang]

It sounds like you have a 160F stat. This can be more chanllenging for emissions. Swap in a stock stat for the test. If the temps are higher than mid gauge, then drop to a 180F.
You should be fine with the stocker though.

An exhaust leak can send a false lean reading to the O2's (fresh air hitting the O2). When the lean reading gets to the computer, the computer enrichens the mixture.

While you are fixing the exhaust leak, check to make sure the cats have not been gutted.
People do this hoping for more power.
If they are damaged, then find some aftermarket high flow cats from Magnaflow or the like.

Pull your codes.
The computer will tell you if one of the O2's is getting out of range readings (exhaust leak), or if the EGR is not functioning properly.

Proportionally speaking, I had very similar test results in my 2.3L. Once I installed a cat (previous owner had removed it), I passed with ease.

let us know how you do,
jason

 

[jrichker]

As mentioned, dump the codes.

Dump the codes and see what the computer says is wrong… Codes can be present without setting the Check Engine Light.

Here's the link to dump the computer codes with only a jumper wire or paper clip and the check engine light, or test light or voltmeter. I’ve used it for years, and it works great.

See http://www.troublecodes.net/Ford/
OR
See http://www.mustangworks.com/articles/electronics/eec-iv_codes.html

IF your car is an 86-88 stang, you'll have to use the test lamp or voltmeter method. There is no functional check engine light on the 86-88's except possibly the Cali Mass Air cars.

Codes have different answers if the engine is running from the answers that it has when the engine isn't running. It helps a lot to know if you had the engine running when you ran the test.

Trouble codes are either 2 digit or 3 digit, there are no cars that use both 2 digit codes and 3 digit codes.

For those who are intimidated by all the wires & connections, see http://www.actron.com/product_detail.php?pid=16153 for what a typical hand scanner looks like. Normal retail price is about $30 or so at AutoZone or Walmart.

Or for a nicer scanner see http://www.midwayautosupply.com/detailedproductdescription.asp?3829 – It has a 3 digit LCD display so that you don’t have to count flashes or beeps.. Cost is $35.

WalMart may have the above LCD display scanner for less than $35.