exhaust hole = this problem?
 

I have horrible hole(s) in my exhaust. The 2 to 1 cat that the passenger side exhaust pipe goes into has a slash thru about 80% of the pipe and then behind it, it has a ton of holes like a shotgun hit it....i tried to patch it temporarily but its not working....could this be why I am getting horrible gas mileage? its losing a ton of exhaust around that area...

Not sure, but don't forget....when your needle is on E....you can probably go another good 50 miles before the fuel light comes on.....It's just a standard thing we have with this car. Make sure you have a good gas cap...(a new one is like 20 bucks from dealer) and also make sure your CE light is not on and the 02 sensors are working properly.

Yes, It will effect the gas mileage a little. Probally the only thing to do in that case it get it fixed. I just got my big hole fixed in mine by getting a custom exhaust done up, But I can't tell you too much about improvements from just that since I got 4.44 gears put in at the same time.:rolleyes: Good luck man.

my check engine light does come on from time to time while driving, it usually pops up once in awhile. I figured it was the exhaust leak that is causing this check engine issue.

Have you pulled the engine codes yet? (Instructions in the SVXipedia)

Likely you're getting a code for one or both of the oxygen sensors.

It more than likely is.

when I first bought my car, the CE light would come on every now and then after I went up a steep hill near the valley I live near....turned out to be two bad oxygen sensors...plus my gas mileage was bad too......I'd get that looked at.

oxygen sensors dealer only? I was under my car yesterday and they looked fried. If im replacing the manifold to the 2to1 cat I might as well replace the o2 sensors also huh? Let me know how much the sensors are if you know off the top of your head.

Little know fact: O2 sensors can sometimes be repaired. 1st step is to remove them and bench test them. You must use a high impedance DC voltmeter. Clamp the sensor in a vice, or use a pliers or vice-grip to hold it. Clamp your negative voltmeter lead to the ground lead wire of the sensor, and the positive to the output lead wire. Use a propane torch set to high and the inner blue flame tip to heat the fluted or perforated area of the sensor. You should see a DC voltage of at least 0.6 within 20 seconds. If not, most likely cause is open circuit internally or oil fouling. If OK so far, remove from flame. You should see a drop to under 0.1 volt within 4 seconds. If not it is likely silicone fouled. If still OK, heat for two full minutes and watch for drops in voltage. Sometimes, the internal connections will open up under heat. This is the same as a loose wire and is a failure. If the sensor is OK at this point, and will switch from high to low quickly as you move the flame, the sensor is good. Bear in mind that good or bad is relative. ANY O2 sensor that will generate 0.9 volts or more when heated, show 0.1 volts or less within one second of flame removal, AND pass the two minute heat test is good regardless of age.

If the sensor tests bad, switch to a MAPP gas or Oxy/Acetylene torch. Heat the perforated area and then remove the heat and blast the sensor with compressed air. Retest, repeat cleaning if necessary, retest. If it does not test normal at this point, replace it. Most sensors that are fouled can be cleaned successfully.

When replacing a sensor, don't miss the opportunity to use the test above on the replacement. This will calibrate your evaluation skills and save you money in the future. There is almost always *no* benefit in replacing an oxygen sensor that will pass the test in the first paragraph.

Doug

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Doug you are the man, im gonna do that. My dad owns a water systems company and we have multiple copies of all those tools you described. I will clean them and test them asap. Is this whats is leading to my rough idling? (besides the huge hole in my exhaust) or should I replace the injectors also?

Test, THEN clean :D

I would change one thing at a time and reset the ECU in between.

As for a rough idle, that can be caused by many things. Vacuum leak, fuel system problem (not necessarily injectors), clogged throttle body, etc.

I highly doubt that at idle, an exhaust leak after the O2 sensors would have any affect on idle performance.

You car would probably benefit from a total fuel system service. Call around to the shops and see who performs the following:
Fuel pump pressure AND volume test.
Pressure regulator test.
Isolated fuel line cleaning.
De-carbonizing through the fuel injector rail and intake.

Not many shops get that involved with a fuel service but it will breath new life into your engine if they do.

Doug