Ok, my friends car just backfires all teh time. Hes got header back piping, with a high flow cat. Well whenever he taps the gas in gear, it ALWAYS backfires like 3-4 times really fast. Would taking out the cat completly, fix that? or is he just screwed? btw...dont ask the car

 

i think it might have something to do with the sparks...and firing order of spark wires. i'm not 100% sure....

 

Well not, the big Boom, like the reuglar exhaust popping.

 

Removing the cat would only make it worse. Lemme guess, hes running a "custom" ecu chip (aka: some production line "performance" chip?). If so, his car is probably running extremely rich and he either needs to get tuned, or get something other than some cookie cutter chip that isnt going to make his car run rich because its not tuned for his setup.

 

How loud is this back firing? Or is it like flames out the back?

When you get bigger pipping youll head and sometimes feel back fire echos. So its a normal thing you might need to get used to. But what causes it is:

1. Timing
2. Running Rich

 

nu uh, no chip at all. Its a saturn ion, and it just alwasy backfires. Intake, header back exhaust, pulley, and thas it.

 

Underdrive pulley? Where does it go on the engine? Is it a smaller crank pulley, or pulley for accessories? Tell him to check his timing.

 

Don't mean to hijack, but I have a similiar question, and it involves a Honda. I just bought a EG with a B16A swap running a chipped P28 with header, free flow cat, and cat back and the wrong 02 sensor to boot. I'm backfiring on allmost every upshift, just one little pop. Will the 02 sensor itself fix that, or does the cat have a lot to do with it.

Thanks

 

My car has the rare flame coming out the exhaust. Then again I have a gutted cat and my car runs pretty rich. Well it did that before I changed my ecu chip. I haven't ripped on it yet with this new chip.

 

The pulley isnt underdriven, just lightened crank pulley. His AFR shows that he is running a little lean, but at WOT its starts to get rich. But it pops all the time, not jsut at rich.

 

check your timing if you haven't

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by TrizzyDizzy &raquo;</TD></TR><TR><TD CLASS="quote">The pulley isnt underdriven, just lightened crank pulley. His AFR shows that he is running a little lean, but at WOT its starts to get rich. But it pops all the time, not jsut at rich.</TD></TR></TABLE>

he might be to lean, make sure is ignition timing is correct for the motor he has.

 

he might have a small vacuum leak around the injectors,or intake manifold.

 

Well the car has 20k miles, and its an 03. I wouldnt think it would have anything to do with leaks or timing, but i guess we can still look into it.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by TrizzyDizzy &raquo;</TD></TR><TR><TD CLASS="quote">Well the car has 20k miles, and its an 03. I wouldnt think it would have anything to do with leaks or timing, but i guess we can still look into it.</TD></TR></TABLE> if so.. wouldn't it still have the warranty? you should take it to the dealer

 

by chance has your friend not taken it to the dealer yet because he voided the warranty by putting all that crap on there. Did he buy factory upgrades or are they aftermarket, because if they are aftermarket the dealer will just laugh. sorry dude

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by eL &raquo;</TD></TR><TR><TD CLASS="quote">My car has the rare flame coming out the exhaust. Then again I have a gutted cat and my car runs pretty rich. Well it did that before I changed my ecu chip. I haven't ripped on it yet with this new chip.</TD></TR></TABLE>

Why are you running a gutted cat? Did you know it is actually worse for power? Assuming you gutted a Honda/Acura cat, un-gutted it would only produce 1-2 LBS of backpressure. A hallow cat causes flow stagnation.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Jonzo &raquo;</TD></TR><TR><TD CLASS="quote">

Why are you running a gutted cat? Did you know it is actually worse for power? Assuming you gutted a Honda/Acura cat, un-gutted it would only produce 1-2 LBS of backpressure. A hallow cat causes flow stagnation.</TD></TR></TABLE>

I didn't gut it for performance reasons.

 

So you don't care that you could be losing performance?

 

you've got an exhaust leak. somewhere around your cat. outside air will seep in through leak and mix with hot unburnt fuel(since you are running rich.

 

what type of a/f gauge does he have? if its narrowband it means jack ****

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Soccerking3000 &raquo;</TD></TR><TR><TD CLASS="quote">what type of a/f gauge does he have? if its narrowband it means jack ****</TD></TR></TABLE>
Yes its narrowband, and i tell him it sucks, but he doesnt listen.

You said an exhaust leak will cause this problem? hmm, ill look into that. Thanks

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by bigxclumzy &raquo;</TD></TR><TR><TD CLASS="quote">you've got an exhaust leak. somewhere around your cat. outside air will seep in through leak and mix with hot unburnt fuel(since you are running rich.</TD></TR></TABLE>

this might be the same situation i have on my single cam..Thanks

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Jonzo &raquo;</TD></TR><TR><TD CLASS="quote">So you don't care that you could be losing performance?</TD></TR></TABLE>

Simply put, no.

 

Can I ask why? I don't mean to be sounding like a dick - but I'm just curious