Emissions problems
- Thread starter BPH90LX
- Start date
when my ranger almost failed smog cause of hydrocarbons, the tester guy said that it will fail in 2 years if i dont upgrade the ignition system. he said that a bad ignition system will cause a high hydrocarbon reading. now would be a good time to upgrade to an msd coil and ignition box if you dont already have it
89CopCoupe
Banned
5.0fox
Member
How to pass emissions testing:
1.) Make sure all the emissions gear the car was made with is present and connected up properly. That includes a working smog pump and cats.
2.) Make sure that you have fresh tune up with spark plugs, plug wires, cap, rotor, fuel & air filters. An oil & filter change is a good idea while you are at it.
3.) Dump the codes and see what the computer says is wrong…
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 $33.
4.) Post the codes and get help to fix them. Don’t try to pass with codes not fixed. Clearing the computer just temporarily removes them from memory, it doesn’t fix the problem that caused the code to be set.
5.) Be sure to do the testing on a hot engine. Drive for 15-20 minutes prior to taking the test to get operating temps up into the normal range. Do not shut off the engine while waiting for your turn on the test machine. An engine up to full operating temperature puts out fewer emissions.
1.) Make sure all the emissions gear the car was made with is present and connected up properly. That includes a working smog pump and cats.
2.) Make sure that you have fresh tune up with spark plugs, plug wires, cap, rotor, fuel & air filters. An oil & filter change is a good idea while you are at it.
3.) Dump the codes and see what the computer says is wrong…
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 $33.
4.) Post the codes and get help to fix them. Don’t try to pass with codes not fixed. Clearing the computer just temporarily removes them from memory, it doesn’t fix the problem that caused the code to be set.
5.) Be sure to do the testing on a hot engine. Drive for 15-20 minutes prior to taking the test to get operating temps up into the normal range. Do not shut off the engine while waiting for your turn on the test machine. An engine up to full operating temperature puts out fewer emissions.
amplifier28
Member
- Apr 16, 2005
- 222
- 1
- 19
I also recently scanned the computer of my 1988 Mustang GT with mass air and pulled the following code: "81". What is needed to fix this code?
BPH90LX said:
12 RPM unable to acheive upper test limit
52 Power Steering pressure switch circuit open
Power Steering pressure switch always open or closed
59 Low speed fuel pump circut open-battery to ECA
AXOD 4/3 pressure switch failed closed
69 AXOD 3/2 prsssure switch circuit failed closed
AXOD 3/4 poressure switch circuit failed open
81 IAS circuit failure
Air management 2 circuit failure
93 TP sensor input low at maximum motor travel
95 Fuel pump secondary circut failure-ECA to ground
Not sure waht they all mean, but it should give you something to go with.
I would start with the IAS because I would think that this would have an affect similar to what you are experiencing.
Good Luck
Critical emissions things:
- clean out the idle air bypass (be sure to have a new gasket handy);
- clean out the EGR valve (be sure to have a new gasket handy);
- set timing within limits, probably 13 degrees BTDC or less, down to 6;
- make sure the distributor cap, rotor, plugs and wires are all up to par;
- run 87 octane, it burns hotter and cleaner;
- when you show for the test DO NOT SHUT OFF THE CAR. The cats must be hot hot hot. Do some blasts on the way over, and keep the car running while you wait;
- a 195 thermostat will probably run cleaner for the test;
- an MSD 6A can not hurt;
- if all else fails, new cats make a huge difference. If the car is otherwise running right, get a new 2.5" h-pipe with fresh cats. This will probably make the biggest difference on a high miler. If you don't already have one you will also like the extra sound and power it offers.
Good luck.
- clean out the idle air bypass (be sure to have a new gasket handy);
- clean out the EGR valve (be sure to have a new gasket handy);
- set timing within limits, probably 13 degrees BTDC or less, down to 6;
- make sure the distributor cap, rotor, plugs and wires are all up to par;
- run 87 octane, it burns hotter and cleaner;
- when you show for the test DO NOT SHUT OFF THE CAR. The cats must be hot hot hot. Do some blasts on the way over, and keep the car running while you wait;
- a 195 thermostat will probably run cleaner for the test;
- an MSD 6A can not hurt;
- if all else fails, new cats make a huge difference. If the car is otherwise running right, get a new 2.5" h-pipe with fresh cats. This will probably make the biggest difference on a high miler. If you don't already have one you will also like the extra sound and power it offers.
Good luck.
good tune up and retarded timing
Retard the timing to about 8-10 degrees. The car will burn cleaner but not make as much power. You can change it back afterwards. Your injectors might be dirty also. It may be a good idea to run a strong injector cleaner, like the RedLine stuff through a tank of gas to clean it out a bit. Might want to put a timing light on ALL of your ignition wires to make sure you are getting good spark to all of them. Just some stuff you might try. Failing emissions sucks.
Retard the timing to about 8-10 degrees. The car will burn cleaner but not make as much power. You can change it back afterwards. Your injectors might be dirty also. It may be a good idea to run a strong injector cleaner, like the RedLine stuff through a tank of gas to clean it out a bit. Might want to put a timing light on ALL of your ignition wires to make sure you are getting good spark to all of them. Just some stuff you might try. Failing emissions sucks.
Code 12 -Idle Air Bypass motor not controlling idle properly (generally idle too low) - IAB dirty or not working. Take it off and clean it thoroughly with throttle body cleaner. Clean the electrical contacts with non flammable brake parts cleaner at the same time.
Code 81 – Secondary Air Injection Diverter Solenoid failure AM2. The solenoid valve located on the back side of the passenger side wheel well is not functional. Possible bad wiring, bad connections, missing or defective solenoid valve. Check the solenoid valve for +12 volts at the Red wire and look for the Lt Green/Black wire to switch from +12 volts to 1 volt or less. The computer controls the valve by providing a ground path on the LT Green/Black wire for the solenoid valve.
See http://www.veryuseful.com/mustang/t...ng5.0Vacuum.gif for help on the vacuum line plumbing.
Code 93 - Throttle linkage binding or bad ISC motor. ISC HO2S not reading Fuel control. The IAB or IAC isn’t controlling the idle. See code 12 if it appears. Clean the IAB and electrical contacts, set the idle speed and TPS.
Try this... Currently there is some dispute about setting it at .99 volts but anything less is probably OK. All you need is less than 1.0 volt at idle and more than 4.25 at Wide Open Throttle (WOT). You'll need a Digital Voltmeter (DVM) to do the job.
The Orange/White wire is the VREF 5 volts from the computer. You use the Dark Green/Lt green wire (TPS signal) and the Black/White wire (TPS ground) to set the TPS
Here’s a TPS tip I got from NoGo50
When you installed the sensor make sure you place it on the peg right and then tighten it down properly. Loosen the back screw a tiny bit so the sensor can pivot and loosen the front screw enough so you can move it just a little in very small increments. I wouldn’t try to adjust it using marks. Set it at .97v-.99v, the closer to .99v the better.
(copied from MustangMax, Glendale AZ)
1. Always adjust the TPS and Idle with the engine at operating temp. Dive it around for a bit if you can and get it nice and warm.
2. When you probe the leads of the TPS, do not use an engine ground, put the ground probe into the lead of the TPS. You should be connecting both meter probes to the TPS and not one to the TPS and the other to ground.
3. Always reset the computer whenever you adjust the TPS or clean/change any sensors. I just pull the battery lead for 10 minutes.
4. Check the procedure for your year, on my 90 I have to turn the idle screw until it just touches the tab, then insert a .010 feeler gauge and give it about one more turn. Then you adjust the TPS voltage to .98v, reset the computer. Start it up, if the idle is to low then turn the screw in until it is just right, then readjust the TPS voltage to .98v and reset the computer and start it up. The key is to adjust the TPS voltage and reset the computer whenever the idle screw is changed.
The primary thing causing you to fail emissons testing is an inoperative smog pump system, also known as the Thermactor Air Injection System.
The smog pump has two vacuum operated valves. The first valve either dumps the pump output to the open air or directs it to the next valve. The smog pump dumps its output at full throttle to save horsepower. The second valve directs the air to either the passages in the heads or to the tube that runs to the cat converters. Both the tube for the head and the tube going to the cat converters have one way check valves to prevent the hot exhaust gas from backing up into the tube and the control valves.
See http://www.veryuseful.com/mustang/tech/engine/images/88Stang5.0Vacuum.gif for smog pump vacuum line help
Here are some of the codes generated by faulty parts in the smog pump system and their fixes...
Codes 94 & 44 - Check vacuum lines for leaks, & cracks. Disconnect the big hose from smog pump: with the engine running you should feel air output. Reconnect the smog pump hose & apply vacuum to the first vacuum controlled valve: Its purpose is to either dump the pump's output to the atmosphere or pass it to the next valve. The next vacuum controlled valve directs the air to either the cylinder heads when the engine is cold or to the catalytic converter when the engine is warm. Disconnect the big hoses from the back side of the vacuum controlled valve and start the engine. Apply vacuum to the valve and see if the airflow changes from one hose to the next.
The two electrical controlled vacuum valves mounted on the rear of the passenger side wheelwell turn the vacuum on & off under computer control. Check to see that both valves have +12 volts on the red wire. Then ground the white/red wire and the first solenoid should open and pass vacuum. Do the same thing to the light green/black wire on the second solenoid and it should open and pass vacuum.
Remember that the computer does not source power for any actuator or relay, but provides the ground necessary to complete the circuit. That means one side of the circuit will always be hot, and the other side will go to ground or below 1 volt as the computer switches on that circuit.
See the following website for some help from Tmoss (diagram designer) & Stang&2Birds (website host)
http://www.veryuseful.com/mustang/tech/engine/images/fuel-alt-links-ign-ac.gif
http://www.veryuseful.com/mustang/tech/engine/images/88-91eecPinout.gif
Code 81 – Secondary Air Injection Diverter Solenoid failure AM2. The secondary air diverter solenoid valve isn’t working on the Thermactor Air System (smog pump). Look for broken or missing vacuum lines on the solenoid valve to the diverter valve. The solenoid valve is located on the back side of the passenger side wheel well. Check the solenoid valve for +12 volts at the Red wire and look for the Lt Green/Black wire to switch from +12 volts to 1 volt or less. The computer controls the valve by providing a ground path on the LT Green/Black wire for the solenoid valve.
Code 82 – Secondary Air Injection Diverter Solenoid failure AM1. The dump valve air diverter solenoid valve isn’t working on the Thermactor Air System (smog pump). Look for broken or missing vacuum lines on the solenoid valve to the diverter valve Check the solenoid valve for +12 volts at the Red wire and look for the Red/White wire to switch from +12 volts to 1 volt or less. The computer controls the valve by providing a ground path on the Red/White wire for the solenoid valve.
Putting the computer into self test mode will cause all the actuators to toggle. This can be done either with a jumper wire or code scanner.
Code 81 – Secondary Air Injection Diverter Solenoid failure AM2. The solenoid valve located on the back side of the passenger side wheel well is not functional. Possible bad wiring, bad connections, missing or defective solenoid valve. Check the solenoid valve for +12 volts at the Red wire and look for the Lt Green/Black wire to switch from +12 volts to 1 volt or less. The computer controls the valve by providing a ground path on the LT Green/Black wire for the solenoid valve.
See http://www.veryuseful.com/mustang/t...ng5.0Vacuum.gif for help on the vacuum line plumbing.
Code 93 - Throttle linkage binding or bad ISC motor. ISC HO2S not reading Fuel control. The IAB or IAC isn’t controlling the idle. See code 12 if it appears. Clean the IAB and electrical contacts, set the idle speed and TPS.
Try this... Currently there is some dispute about setting it at .99 volts but anything less is probably OK. All you need is less than 1.0 volt at idle and more than 4.25 at Wide Open Throttle (WOT). You'll need a Digital Voltmeter (DVM) to do the job.
The Orange/White wire is the VREF 5 volts from the computer. You use the Dark Green/Lt green wire (TPS signal) and the Black/White wire (TPS ground) to set the TPS
Here’s a TPS tip I got from NoGo50
When you installed the sensor make sure you place it on the peg right and then tighten it down properly. Loosen the back screw a tiny bit so the sensor can pivot and loosen the front screw enough so you can move it just a little in very small increments. I wouldn’t try to adjust it using marks. Set it at .97v-.99v, the closer to .99v the better.
(copied from MustangMax, Glendale AZ)
1. Always adjust the TPS and Idle with the engine at operating temp. Dive it around for a bit if you can and get it nice and warm.
2. When you probe the leads of the TPS, do not use an engine ground, put the ground probe into the lead of the TPS. You should be connecting both meter probes to the TPS and not one to the TPS and the other to ground.
3. Always reset the computer whenever you adjust the TPS or clean/change any sensors. I just pull the battery lead for 10 minutes.
4. Check the procedure for your year, on my 90 I have to turn the idle screw until it just touches the tab, then insert a .010 feeler gauge and give it about one more turn. Then you adjust the TPS voltage to .98v, reset the computer. Start it up, if the idle is to low then turn the screw in until it is just right, then readjust the TPS voltage to .98v and reset the computer and start it up. The key is to adjust the TPS voltage and reset the computer whenever the idle screw is changed.
The primary thing causing you to fail emissons testing is an inoperative smog pump system, also known as the Thermactor Air Injection System.
The smog pump has two vacuum operated valves. The first valve either dumps the pump output to the open air or directs it to the next valve. The smog pump dumps its output at full throttle to save horsepower. The second valve directs the air to either the passages in the heads or to the tube that runs to the cat converters. Both the tube for the head and the tube going to the cat converters have one way check valves to prevent the hot exhaust gas from backing up into the tube and the control valves.
See http://www.veryuseful.com/mustang/tech/engine/images/88Stang5.0Vacuum.gif for smog pump vacuum line help
Here are some of the codes generated by faulty parts in the smog pump system and their fixes...
Codes 94 & 44 - Check vacuum lines for leaks, & cracks. Disconnect the big hose from smog pump: with the engine running you should feel air output. Reconnect the smog pump hose & apply vacuum to the first vacuum controlled valve: Its purpose is to either dump the pump's output to the atmosphere or pass it to the next valve. The next vacuum controlled valve directs the air to either the cylinder heads when the engine is cold or to the catalytic converter when the engine is warm. Disconnect the big hoses from the back side of the vacuum controlled valve and start the engine. Apply vacuum to the valve and see if the airflow changes from one hose to the next.
The two electrical controlled vacuum valves mounted on the rear of the passenger side wheelwell turn the vacuum on & off under computer control. Check to see that both valves have +12 volts on the red wire. Then ground the white/red wire and the first solenoid should open and pass vacuum. Do the same thing to the light green/black wire on the second solenoid and it should open and pass vacuum.
Remember that the computer does not source power for any actuator or relay, but provides the ground necessary to complete the circuit. That means one side of the circuit will always be hot, and the other side will go to ground or below 1 volt as the computer switches on that circuit.
See the following website for some help from Tmoss (diagram designer) & Stang&2Birds (website host)
http://www.veryuseful.com/mustang/tech/engine/images/fuel-alt-links-ign-ac.gif
http://www.veryuseful.com/mustang/tech/engine/images/88-91eecPinout.gif
Code 81 – Secondary Air Injection Diverter Solenoid failure AM2. The secondary air diverter solenoid valve isn’t working on the Thermactor Air System (smog pump). Look for broken or missing vacuum lines on the solenoid valve to the diverter valve. The solenoid valve is located on the back side of the passenger side wheel well. Check the solenoid valve for +12 volts at the Red wire and look for the Lt Green/Black wire to switch from +12 volts to 1 volt or less. The computer controls the valve by providing a ground path on the LT Green/Black wire for the solenoid valve.
Code 82 – Secondary Air Injection Diverter Solenoid failure AM1. The dump valve air diverter solenoid valve isn’t working on the Thermactor Air System (smog pump). Look for broken or missing vacuum lines on the solenoid valve to the diverter valve Check the solenoid valve for +12 volts at the Red wire and look for the Red/White wire to switch from +12 volts to 1 volt or less. The computer controls the valve by providing a ground path on the Red/White wire for the solenoid valve.
Putting the computer into self test mode will cause all the actuators to toggle. This can be done either with a jumper wire or code scanner.
amplifier28
Member
- Apr 16, 2005
- 222
- 1
- 19
Can you find the "Secondary Air Injection Diverter Solenoid" at most parts stores? Do they cost a lot?
amplifier28
Member
- Apr 16, 2005
- 222
- 1
- 19
I searched autozone.com for the "Secondary Air Injection Diverter Solenoid" and only found a listing for air pump valves. There were two types: upstream and downstream valves. Are these it? What is the OEM number for the "Secondary Air Injection Diverter Solenoid"? Do I buy the solenoid or the valve? Which do I need? Information greatly appreciated.
A trip to the j/y gets you the solnoid valve you need. They are located in pairs on the aftside of the passenger side wheel well.
Check the valve for operation and don't just throw parts at the problem. Remove the large rubber hoses from the rear of the aft vacuum control valve. One hose goes to the pipe to the back of the heads. The other hose goes to the pipe that goes to the cat converters. Start the engine and apply vacuum (steal a line from the manifold somewhere) the airflow out of the valve should switch from one outlet to the other. If it doesn't then the vacuum control valve is bad.
With the engine running, stick a safety pin in the LT Green/Black wire for the solenoid valve & ground it. That should turn the solenoid on and cause air to flow out the port that goes to the pipe connected to the cats. If it doesn't, the valve is bad. If it does cause the airflow to switch, the computer or wiring going to the computer is not signaling the solenoid valve to open.
Check the valve for operation and don't just throw parts at the problem. Remove the large rubber hoses from the rear of the aft vacuum control valve. One hose goes to the pipe to the back of the heads. The other hose goes to the pipe that goes to the cat converters. Start the engine and apply vacuum (steal a line from the manifold somewhere) the airflow out of the valve should switch from one outlet to the other. If it doesn't then the vacuum control valve is bad.
With the engine running, stick a safety pin in the LT Green/Black wire for the solenoid valve & ground it. That should turn the solenoid on and cause air to flow out the port that goes to the pipe connected to the cats. If it doesn't, the valve is bad. If it does cause the airflow to switch, the computer or wiring going to the computer is not signaling the solenoid valve to open.
amplifier28
Member
- Apr 16, 2005
- 222
- 1
- 19
amplifier28
Member
- Apr 16, 2005
- 222
- 1
- 19
Hey "jrichker"
I saw under the hood behind the passenger wheel well.There was a small black container above two small containers. Do all three container come together?
I saw under the hood behind the passenger wheel well.There was a small black container above two small containers. Do all three container come together?
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