Huge Backfire Problem. Help!!!
05-15-2003, 06:46 PM
#1
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Huge Backfire Problem. Help!!!
I am having a problem with Backfire. I Got a Turbo back and took out all the cats, replaced my up-pipe and then got a BOV. since i put in the BOV my backfire is much worse. It happens when I let off the gas and sometimes when i am at an idle. I sent my wrx to get my whole exhaust Re-Installed and at the same time got the header replaced. It happens less frequent now but has gotten louder. What can I do to fix my Backfire?
05-16-2003, 04:26 PM
#6
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'Backfires' are evil- that means that your intake valves are slightly open during combustion and fuel is being burned in the intake manifold- bad! But that's not what your getting- you're getting some unburnt fuel in your exhaust, which is spontaneously igniting and making the noises most people call backfires. Catalytic converters do this before they get to places they can make the noise.
'Rich' means there is too much fuel in your combustion chambers to completely react with the oxygen. You need more airflow, or less fuel.
'Rich' means there is too much fuel in your combustion chambers to completely react with the oxygen. You need more airflow, or less fuel.
05-17-2003, 10:56 AM
#8
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a aftermarket BOV causes the engine to run rich, you should either get a 50/50 Hybrid to send some air back into the intake like the ECU is mapped for, that will help slightly 
or just reinstall the stock BOV which is a great BOV until you do major mods eg. larger turbo
or just reinstall the stock BOV which is a great BOV until you do major mods eg. larger turbo
05-17-2003, 11:20 AM
#9
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the octane rating of the fuel you use has nothing to do with backfires, or running rich. octane is simply a measure of how resistant a fuel is to premature detonation i.e. the air/fuel mixture igniting due to compression, before the spark plug fires.
and a/f gauge could help you fix the problem, but it's only going to tell you that you'r running rich. to fix the rich mixture issue, you could have your ECU remapped, get an aftermarket ECU, or some sort of A/F controller. if you do, i'd reccomend having a pro install it unless you really know what you're doing.
a blowoff valve won't cause a constant rich mixture condition, it'll only force additional fuel into the combustion chambers when the throttle is lifted and excess pressure is vented. if you're only getting backfires when you lift the throttle, pull off the BOV and that should help a whole lot.
and a/f gauge could help you fix the problem, but it's only going to tell you that you'r running rich. to fix the rich mixture issue, you could have your ECU remapped, get an aftermarket ECU, or some sort of A/F controller. if you do, i'd reccomend having a pro install it unless you really know what you're doing.
a blowoff valve won't cause a constant rich mixture condition, it'll only force additional fuel into the combustion chambers when the throttle is lifted and excess pressure is vented. if you're only getting backfires when you lift the throttle, pull off the BOV and that should help a whole lot.
05-17-2003, 01:53 PM
#10
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You could get some form of programable engine management. It puts you in control of richness vs. leanness, and a few other goodies depending on which model you choose.
05-23-2003, 09:46 AM
#13
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if you get the AEM short ram intake, it tricks your engine into running leaner. which is good and bad...but good for you! i used to get that little black smoke out the back, cause w's run rich, but since i put the intake in...i barely get it! try that. i got mine for 155 with shipping off ebay.
05-23-2003, 11:47 AM
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Originally posted by Boneamania
if you get the AEM short ram intake, it tricks your engine into running leaner. which is good and bad...but good for you! i used to get that little black smoke out the back, cause w's run rich, but since i put the intake in...i barely get it! try that. i got mine for 155 with shipping off ebay.
if you get the AEM short ram intake, it tricks your engine into running leaner. which is good and bad...but good for you! i used to get that little black smoke out the back, cause w's run rich, but since i put the intake in...i barely get it! try that. i got mine for 155 with shipping off ebay.