check engine light
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check engine light
97 Acura TL 3.2L code P401 low flow in egr valve i changed the egr valve and all the sensors but the check engine light still comes back on can anybody help me?I can't pass emmissions!
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Joined: May 2008
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From: Signal mountain, TN
You can pass the emissions test if you use your OBDII analyzer to turn the codes off just before arriving at the emissions station. It will pass in at least two states.
But that is not to say that this is a fix.
You need to clean the suction side of your EGR passages. It is very easy.
You will find your EGR valve at the back of the engine intake manifold. It is quite easy to take out. You need a 3/8 drive socket with a six inch extension and a 12mm socket. Remove the 4 nuts and two bolts that hold the cross-tower support assembly. Slide the air conditioner tubing from the three crescent holders and pull the support out.
There are two 12mm nuts that hold the EGR valve in the manifold. Be very careful to hold onto the nuts as you spin them off. Rush this and you will drop them into an amazingly inaccessible part of your underhood area. (just a guess, of course.
There is a tough, two-port gasket under the EGR. You may reuse it almost indefinitely. The problem is the larger, mostly rectangular, port. It is the suction side and the carbon buildup from your BP or Amoco gas is probably what caused it to sulfidate.
A complete blockage of this port will allow it to hold a liquid to the rim. If it were open, a liquid would simply continue into the manifold. If it fills with about 4 ounces of liquid, you have a carbonized dam about 8 inches in.
Some say that you need to disassemble the manifold and scrub out the entire area. You don't.
Wear goggles while you pour in a couple ounces of KUTZIT paint remover, then top that off with some Acetone. It will not explode, but it will bubble amazingly usefully. Walk away and have a beer or two. The carbon will soften and dissolve after 15 minutes or less.
Place a towel or some shop towels over the area and crank the engine. Carbon will blow out of the ports in chunks.
Reassemble and start the engine. It will take a few tries and some serious white smoke will blow out the exhaust for a minute or so.
Several new codes will show up on your OBDII engine analyzer after this. Clear them. You are good to go for another 30-50,000 miles.
Repeat. This is a crappy design for an EGR system, but I have come around to this fix after wasting more than a thousand dollars on EGR valves and even paying a clown to take the manifold apart.
You can also drill out the carbon dam with a 12 inch piece of old style speedometer cable in conjunction with the witch's brew of Kutzit and Acetone.
But that is not to say that this is a fix.
You need to clean the suction side of your EGR passages. It is very easy.
You will find your EGR valve at the back of the engine intake manifold. It is quite easy to take out. You need a 3/8 drive socket with a six inch extension and a 12mm socket. Remove the 4 nuts and two bolts that hold the cross-tower support assembly. Slide the air conditioner tubing from the three crescent holders and pull the support out.
There are two 12mm nuts that hold the EGR valve in the manifold. Be very careful to hold onto the nuts as you spin them off. Rush this and you will drop them into an amazingly inaccessible part of your underhood area. (just a guess, of course.
There is a tough, two-port gasket under the EGR. You may reuse it almost indefinitely. The problem is the larger, mostly rectangular, port. It is the suction side and the carbon buildup from your BP or Amoco gas is probably what caused it to sulfidate.
A complete blockage of this port will allow it to hold a liquid to the rim. If it were open, a liquid would simply continue into the manifold. If it fills with about 4 ounces of liquid, you have a carbonized dam about 8 inches in.
Some say that you need to disassemble the manifold and scrub out the entire area. You don't.
Wear goggles while you pour in a couple ounces of KUTZIT paint remover, then top that off with some Acetone. It will not explode, but it will bubble amazingly usefully. Walk away and have a beer or two. The carbon will soften and dissolve after 15 minutes or less.
Place a towel or some shop towels over the area and crank the engine. Carbon will blow out of the ports in chunks.
Reassemble and start the engine. It will take a few tries and some serious white smoke will blow out the exhaust for a minute or so.
Several new codes will show up on your OBDII engine analyzer after this. Clear them. You are good to go for another 30-50,000 miles.
Repeat. This is a crappy design for an EGR system, but I have come around to this fix after wasting more than a thousand dollars on EGR valves and even paying a clown to take the manifold apart.
You can also drill out the carbon dam with a 12 inch piece of old style speedometer cable in conjunction with the witch's brew of Kutzit and Acetone.