no cats, no hpipe, running rich?


Please ask me how much my supercharger cost
Apr 6, 2004
Texas City TX
quick question

Would no cats and no h pipe, just straight pipes, cause a car to run rich??? Reason i ask is because my car has always ran rich and i still havent gotten to the bottom of it, was just wondering if maybe this had something to do with it...I still have my smog pump too which obviously serves no purpose without cats...
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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 for more descriptive help

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 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 – It has a 3 digit LCD display so that you don’t have to count flashes or beeps.. Cost is $33.

Look for codes 41, 91, 21, 23. There are more codes that will adversely affect your mileage, but off the top of my head, that's all I can think of at this time.