Okay, the ongoing saga of trying to get emissions tested.
Got rid of the misfire code. Then a solenoid in the trans crapped out and produced a P0750 Shift Solenoid 'A' dtc. (For anyone that hasn't read that thread, it's the solenoid wirth the green connector that is mounted to the valve body in the transaxle. Easy to get to, easy to replace. Get a replacement at the junkyard. And change your trans filter, too.)
Fixed that.
Got inspected. The car, not me. Failed because the battery had been disconnected, the computer reset and I had not driven it far/long enough for the PCM to recalibrate, meditate, contemplate whatever it does in trying to 'get happy'. Four or five snesors had not been tested and it showed the self tests as incomplete.
I figured if it was going to be a few days, I'd take care of something else that needed attention.
Had a P0400 code awhile back that mysteriously vanished while installing a stereo and I disconnected the battery...go figure.
Anyway, it hasn't come back up, but I hadn't done anything to correct. So, it is just a matter of time.
Thought it wise to investigate the EGR.
The first step in the Haynes manual is to check resistance at the EGR Valve Position Sensor. It shows three terminals: 'a', 'b', 'c'. You should read like 2.7 ohms or something, I forget...but the neat thing is that my sensor has 6 terminals! I got no readings between any pairs that showed anything other than 0 ohms or infinite ohms. They were totally open or totally closed. Still have no idea about that.
Being an EGR system, it is prone to clogging. Next step is to clean it all out.
1-Take out the airbox and intake hose.
2-Remove throttle body. Do not spindle, fold, or mutilate the gasket. Unless you want to buy a new one.
3-Remove bolt that holds metal EGR tube to bracket under distributor.
4-Unbolt EGR tube from intake manifold. Gently pull it back to expose the hole in the intake manifold. Carefully remove gasket (remember the warning above, otherwise it can get expensive and inconvenient). Unless you feel really confident that the fitting at the exhaust manifold will come loose nicely, I wouldn't touch it. It would be nice to completely unbolt it, but if something goes wrong, you'll be really unhappy. You might throw wrenches at the car, which is not good. You could damage the wrenches.
5-Disconnect EGR Valve Position Sensor connector.
6-Remove EGR Valve from intake manifold (two bolts). Yep, another gasket...be gentle or shake your wallet upside down at the parts store.
7-Cleaning the EGR valve: I removed the four phillips head screws and separated the sensor body from the valve, this allows you to move the valve pintle (the valve) back and forth. Soak with carb cleaner. A small pick or straightblade screwdriver works well to get rid of alot of the carbon. Once you think it's pretty clean (you can turn the valve and see all the seating surface) soak a paper towel or green kitchen scrubby with carb cleaner (a fresh one, old ones have lots of bacteria. In fact, if you have an old one, throw it out, it's nasty), push the valve shaft down to open the valve and stick the scrubby in there so it jams the valve open. Now turn the valve so it is scrubbed by the scrubby (odd how well they work for scrubbing, huh?).
When it looks clean it probably is.
There are several passages to clean and they can be difficult without removing more parts from the engine...like the intake manifold (which means another gasket to buy) and the injectors and rail (that means having replacement injector o-rings, which means more money. Or actually, less of it by the time you get all those parts)
So here is what I did:
I got:
-a roll of bailing wire (a tough but bendable solid wire from the hardware store, kind of like coat hanger wire but less prone to breaking),
-a couple cans of carb cleaner,
-some small diameter polyethylene tubing (should be able to it in the plumbing department, but I had some left over from installing an oil pressure gauge. It shouldn't really be any larger than 1/16th inch in diameter and the straw tube from the carb cleaner can should fit in it).
-and an air supply (not the 80's lite rock band, but a compressor or air tank) with a hose and nozzle (preferably one that has the lever trigger).
8-Spray carb cleaner inside all the holes/passages:
-the metal EGR tube (if you can, it's turned away from any decent access)
-all the holes in the intake manifold: the EGR tube hole, both passages where the EGR valve bolts to the intake, and there are three more holes inside the intake behind where the throttlebody bolts on. One is a passage in the floor of the intake about a inch or so in (it looks like a bump, but it is just a raised area around the passage). Another is in the slot at the top of the gasket/throttle body mating surface of the intake manifold. You can see the passage cast into the manifold as it goes a couple inches straight back towards the firewall. A rubber hose is connected to it. Pop the hose off and spray from the slot side of the passage. Stick a piece of wire in it where the hose connects and you should see the end of the wire at the slot. You will be able to tell if there is carbon in there or not.
The next passage is inside the intake just behind the one in the slot. You get to it from inside the intake and go up. You can see the large casting bulges on the outside of the intake. The passage goes straight up, then turns horizontal towards the firewall, then turns down towards the EGR valve. You can't just spray up into it as it will just spray right back out.
Now, the trick to all this is to get a feel for handling the wire. Cut a piece about a foot long. Make a little curve right at the end, but not too much. What you are trying to do is feed that wire up into that upper passage and get it to make that first turn so you can push a few inches of wire past it. You may have to work it back and forth a bit. A pair of plyers might be of some help.
You can use the same technique to get some of the carbon out of the other passages. The metal EGR tube is a pain. I was more successful getting a foot or so of the polyethylene tubing to make three of the four turns in the metal tube. The wire was just too stiff. A little grease wouldn't hurt, just don't get it on your hands or where you hold the tubing.
After you get the wire into that upper passage, do the same thing with 6" of the poly tubing. Work it back and forth a little, then stick the straw nozzle of the can of carb cleaner into the tubing (cover the joint with your fingers, it weill spray out there too) and spray into it. This gets the carb cleaner up into that passage so it can soak in and loosen stuff up. Unless that passage is totally clogged, you should see carb cleaner run out of one of the holes where the EGR valve bolts on. The same procedure will work on the other passages. If I remember right, the passage in the floor of the intake connects to the other hole where the EGR valve bolts on.
Repeat the above until you feel good about how much carb cleaner comes out at the valve holes.
Once you are pretty sure all the carbong is out that you are able to get out, use the air supply (hopefully you have a hose and nozzle, not a cassette tape...) and stick the nozzle into the various passages (probably need to get some rubber hose to go from the nozzle to the passages). Give it some air and see what comes out (remember to wear protection! For your eyes, not ole' one eye! Not a bad idea, but that is a discussion for another board).
This is basically to make sure the passages do flow. You can put your fingers over the EGR valve holes to see if air is flowing.
If the metal EGR tube is still attached to the exhaust manifold, stick the nozzle in the other end and blow air towards the exhaust manifold (helps to have a friend...won't say anymore about that...). While one person is blowing the air, the other goes back to the exhaust pipe and listens. If you have 50 psi or so, you will hear and feel air coming out of the tail pipe. If you do, then the metal tube is clear. If you don't, then it might be clogged. Or your cat converter it clogged. Or Puggsly stuck a potato in your exhaust pipe.
Clean the gaskets (the ones you were so careful with) and reassemble everything. If any are damaged, get new ones.
Even though I am still doing the PCM reset drive cycle, I can tell the difference in the car. Mileage is up and the idle is steadier. 180 miles and no codes. I went by AutoZone and had them hookup their scanner. It showed no codes and said 'Pass' (whatever that means in Actron-speak). I figured if the reset selftest was not done the scanner results would be inconclusive, that the PCM would not be able tell their scanner that everything was okay.
I think. It could be that all their scanner does is read for codes and if there are none, my PCM good give it a recipe for coffe cake and their scanner wouldn't know the difference. But since the Actron screen had the word 'Pass', I think everything is okay and ready for reinspection.
Still have no clue about the EGR Valve Sensor.
Got rid of the misfire code. Then a solenoid in the trans crapped out and produced a P0750 Shift Solenoid 'A' dtc. (For anyone that hasn't read that thread, it's the solenoid wirth the green connector that is mounted to the valve body in the transaxle. Easy to get to, easy to replace. Get a replacement at the junkyard. And change your trans filter, too.)
Fixed that.
Got inspected. The car, not me. Failed because the battery had been disconnected, the computer reset and I had not driven it far/long enough for the PCM to recalibrate, meditate, contemplate whatever it does in trying to 'get happy'. Four or five snesors had not been tested and it showed the self tests as incomplete.
I figured if it was going to be a few days, I'd take care of something else that needed attention.
Had a P0400 code awhile back that mysteriously vanished while installing a stereo and I disconnected the battery...go figure.
Anyway, it hasn't come back up, but I hadn't done anything to correct. So, it is just a matter of time.
Thought it wise to investigate the EGR.
The first step in the Haynes manual is to check resistance at the EGR Valve Position Sensor. It shows three terminals: 'a', 'b', 'c'. You should read like 2.7 ohms or something, I forget...but the neat thing is that my sensor has 6 terminals! I got no readings between any pairs that showed anything other than 0 ohms or infinite ohms. They were totally open or totally closed. Still have no idea about that.
Being an EGR system, it is prone to clogging. Next step is to clean it all out.
1-Take out the airbox and intake hose.
2-Remove throttle body. Do not spindle, fold, or mutilate the gasket. Unless you want to buy a new one.
3-Remove bolt that holds metal EGR tube to bracket under distributor.
4-Unbolt EGR tube from intake manifold. Gently pull it back to expose the hole in the intake manifold. Carefully remove gasket (remember the warning above, otherwise it can get expensive and inconvenient). Unless you feel really confident that the fitting at the exhaust manifold will come loose nicely, I wouldn't touch it. It would be nice to completely unbolt it, but if something goes wrong, you'll be really unhappy. You might throw wrenches at the car, which is not good. You could damage the wrenches.
5-Disconnect EGR Valve Position Sensor connector.
6-Remove EGR Valve from intake manifold (two bolts). Yep, another gasket...be gentle or shake your wallet upside down at the parts store.
7-Cleaning the EGR valve: I removed the four phillips head screws and separated the sensor body from the valve, this allows you to move the valve pintle (the valve) back and forth. Soak with carb cleaner. A small pick or straightblade screwdriver works well to get rid of alot of the carbon. Once you think it's pretty clean (you can turn the valve and see all the seating surface) soak a paper towel or green kitchen scrubby with carb cleaner (a fresh one, old ones have lots of bacteria. In fact, if you have an old one, throw it out, it's nasty), push the valve shaft down to open the valve and stick the scrubby in there so it jams the valve open. Now turn the valve so it is scrubbed by the scrubby (odd how well they work for scrubbing, huh?).
When it looks clean it probably is.
There are several passages to clean and they can be difficult without removing more parts from the engine...like the intake manifold (which means another gasket to buy) and the injectors and rail (that means having replacement injector o-rings, which means more money. Or actually, less of it by the time you get all those parts)
So here is what I did:
I got:
-a roll of bailing wire (a tough but bendable solid wire from the hardware store, kind of like coat hanger wire but less prone to breaking),
-a couple cans of carb cleaner,
-some small diameter polyethylene tubing (should be able to it in the plumbing department, but I had some left over from installing an oil pressure gauge. It shouldn't really be any larger than 1/16th inch in diameter and the straw tube from the carb cleaner can should fit in it).
-and an air supply (not the 80's lite rock band, but a compressor or air tank) with a hose and nozzle (preferably one that has the lever trigger).
8-Spray carb cleaner inside all the holes/passages:
-the metal EGR tube (if you can, it's turned away from any decent access)
-all the holes in the intake manifold: the EGR tube hole, both passages where the EGR valve bolts to the intake, and there are three more holes inside the intake behind where the throttlebody bolts on. One is a passage in the floor of the intake about a inch or so in (it looks like a bump, but it is just a raised area around the passage). Another is in the slot at the top of the gasket/throttle body mating surface of the intake manifold. You can see the passage cast into the manifold as it goes a couple inches straight back towards the firewall. A rubber hose is connected to it. Pop the hose off and spray from the slot side of the passage. Stick a piece of wire in it where the hose connects and you should see the end of the wire at the slot. You will be able to tell if there is carbon in there or not.
The next passage is inside the intake just behind the one in the slot. You get to it from inside the intake and go up. You can see the large casting bulges on the outside of the intake. The passage goes straight up, then turns horizontal towards the firewall, then turns down towards the EGR valve. You can't just spray up into it as it will just spray right back out.
Now, the trick to all this is to get a feel for handling the wire. Cut a piece about a foot long. Make a little curve right at the end, but not too much. What you are trying to do is feed that wire up into that upper passage and get it to make that first turn so you can push a few inches of wire past it. You may have to work it back and forth a bit. A pair of plyers might be of some help.
You can use the same technique to get some of the carbon out of the other passages. The metal EGR tube is a pain. I was more successful getting a foot or so of the polyethylene tubing to make three of the four turns in the metal tube. The wire was just too stiff. A little grease wouldn't hurt, just don't get it on your hands or where you hold the tubing.
After you get the wire into that upper passage, do the same thing with 6" of the poly tubing. Work it back and forth a little, then stick the straw nozzle of the can of carb cleaner into the tubing (cover the joint with your fingers, it weill spray out there too) and spray into it. This gets the carb cleaner up into that passage so it can soak in and loosen stuff up. Unless that passage is totally clogged, you should see carb cleaner run out of one of the holes where the EGR valve bolts on. The same procedure will work on the other passages. If I remember right, the passage in the floor of the intake connects to the other hole where the EGR valve bolts on.
Repeat the above until you feel good about how much carb cleaner comes out at the valve holes.
Once you are pretty sure all the carbong is out that you are able to get out, use the air supply (hopefully you have a hose and nozzle, not a cassette tape...) and stick the nozzle into the various passages (probably need to get some rubber hose to go from the nozzle to the passages). Give it some air and see what comes out (remember to wear protection! For your eyes, not ole' one eye! Not a bad idea, but that is a discussion for another board).
This is basically to make sure the passages do flow. You can put your fingers over the EGR valve holes to see if air is flowing.
If the metal EGR tube is still attached to the exhaust manifold, stick the nozzle in the other end and blow air towards the exhaust manifold (helps to have a friend...won't say anymore about that...). While one person is blowing the air, the other goes back to the exhaust pipe and listens. If you have 50 psi or so, you will hear and feel air coming out of the tail pipe. If you do, then the metal tube is clear. If you don't, then it might be clogged. Or your cat converter it clogged. Or Puggsly stuck a potato in your exhaust pipe.
Clean the gaskets (the ones you were so careful with) and reassemble everything. If any are damaged, get new ones.
Even though I am still doing the PCM reset drive cycle, I can tell the difference in the car. Mileage is up and the idle is steadier. 180 miles and no codes. I went by AutoZone and had them hookup their scanner. It showed no codes and said 'Pass' (whatever that means in Actron-speak). I figured if the reset selftest was not done the scanner results would be inconclusive, that the PCM would not be able tell their scanner that everything was okay.
I think. It could be that all their scanner does is read for codes and if there are none, my PCM good give it a recipe for coffe cake and their scanner wouldn't know the difference. But since the Actron screen had the word 'Pass', I think everything is okay and ready for reinspection.
Still have no clue about the EGR Valve Sensor.
Comment