91 Coupe Backfiring after Hooker header install!
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Drifting
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From: Patchogue NY
91 Coupe Backfiring after Hooker header install!
Car is backfiring when I rev it hard, such as before I shut it off. Installed hooker #2149, and a crap Hypertech chip. I am running 93 octane it. Car ran fine prior to the chip installation. I know, take the chip out and see if that makes a difference. What say gang?
Joe B.
Joe B.
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From: Aiea Hawaii
Originally Posted by joe3906
Car is backfiring when I rev it hard, such as before I shut it off. Installed hooker #2149, and a crap Hypertech chip. I am running 93 octane it. Car ran fine prior to the chip installation. I know, take the chip out and see if that makes a difference. What say gang?
Joe B.
Joe B.
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Drifting
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From: Patchogue NY
It's just a matter of pulling the piggy back chip out, but I didn't put it in, so I'm going to bring it back to "ye ole mechanic," and let him deal with it. I was just wondering if there was something I didn't know about the chip that I might have missed. I'll keep the forum advised.
Thanks for the feed back.
Joe B.
Thanks for the feed back.
Joe B.
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Thread Starter
Drifting
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From: Patchogue NY
In addition to the backfiring, the car threw a code 32. Took it to the mechanic and he say's it has to do with the EGR. Mind you, I just installed Hooker (2149) headers, which come with the pollution set-up. Can someone shed some light on why a code 32 would go off? I took the hypertech chip out of the car. Noticed no difference in the performance, but that code did not come back on. Mechanic said that it would not make a difference with or without the chip. Is there a way of having a custom chip flashed that will deal with the code 32, that's assuming it comes back?
Thanks in advance.
Joe B.
Thanks in advance.
Joe B.
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Well the best way to deal with code 32 would be to fix it. Correct me if I'm wrong but I believe that when the car commands the EGR it should see some change in the way the engine runs. If it does not see that change it will set a code 32.
There isn't really a way to "disable" EGR, but rather program the computer to never command it. At least on the 92 that's how you have to do it, set the EGR enable temperature so high that the engine will be melted into slag and it'll never come on. Since the computer never commands EGR, it never expects it and thus makes other changes to make the engine run OK. It can possibly affect your emissions though on a stock cam. For a slightly more radical cam, such as the LT4 Hot Cam, you don't even really need EGR, it's redundant. Remember the LT4 didn't even have it.
As for the misfire.. a sticking EGR valve can certainly cause a car to run like crap. There's no change that you got the number 5 & 7 wires crossed is there? We wouldn't know anybody who has done that recently..................
There isn't really a way to "disable" EGR, but rather program the computer to never command it. At least on the 92 that's how you have to do it, set the EGR enable temperature so high that the engine will be melted into slag and it'll never come on. Since the computer never commands EGR, it never expects it and thus makes other changes to make the engine run OK. It can possibly affect your emissions though on a stock cam. For a slightly more radical cam, such as the LT4 Hot Cam, you don't even really need EGR, it's redundant. Remember the LT4 didn't even have it.
As for the misfire.. a sticking EGR valve can certainly cause a car to run like crap. There's no change that you got the number 5 & 7 wires crossed is there? We wouldn't know anybody who has done that recently..................
Thread Starter
Drifting
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From: Patchogue NY
Wires were never touched, car was running great prior to the headers going in. Mechanic states "because the hookers, high flo cat, Borla cat-back make the exhaust system way lessl restrictive, the EGR thinks there's a problem and throws the code. Drove the car 25 miles from the mechanic to my house, and now code was thrown. Again, I asked him to take the Hypertech out of the car. Am I wrong in assuming that there is a connection between no code being thrown, and the chip out of the car? By the way, I checked the part No. via the Hypertech website, it is the correct chip.
My car is an L98; I don't know if there's an adjustment on the EGR on my car as you described on your 92 vehicle.
Thanks for your feed back.
Joe B.
My car is an L98; I don't know if there's an adjustment on the EGR on my car as you described on your 92 vehicle.
Thanks for your feed back.
Joe B.
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Originally Posted by joe3906
Wires were never touched, car was running great prior to the headers going in. Mechanic states "because the hookers, high flo cat, Borla cat-back make the exhaust system way lessl restrictive, the EGR thinks there's a problem and throws the code. Drove the car 25 miles from the mechanic to my house, and now code was thrown. Again, I asked him to take the Hypertech out of the car. Am I wrong in assuming that there is a connection between no code being thrown, and the chip out of the car? By the way, I checked the part No. via the Hypertech website, it is the correct chip.
My car is an L98; I don't know if there's an adjustment on the EGR on my car as you described on your 92 vehicle.
Thanks for your feed back.
Joe B.
My car is an L98; I don't know if there's an adjustment on the EGR on my car as you described on your 92 vehicle.
Thanks for your feed back.
Joe B.
I don't know why but the Hypertech may have it disabled.
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From: Phila., PA burbs
My 91 also got the dreaded code 32 aftyer I started making the exhaust less restrictive. I replaced every damn piece of EGR equipment trying to fix it, but to no avail. As Nathan suggested I ended up having a custom chip burned that elimianted the code.
As for your backfire, I'm not sure if the chip itself is the cause (although it could easily be) but I would at least make sure its in properly. Its very easy to bend one of those little prongs on install or to not have the chip seated properly. Either of these would cause the car to run like crap (if at all). I've installed custom chips on several cars and nearly every time on the first start they ran crappy and I had to re-seat the chip.
Either way I'd dump the hypercrap chip. The only real benefit you're seeing is the fan coming on at an earlier temp and you can get a lower temp fan switch for a fraction of the cost.
As for your backfire, I'm not sure if the chip itself is the cause (although it could easily be) but I would at least make sure its in properly. Its very easy to bend one of those little prongs on install or to not have the chip seated properly. Either of these would cause the car to run like crap (if at all). I've installed custom chips on several cars and nearly every time on the first start they ran crappy and I had to re-seat the chip.
Either way I'd dump the hypercrap chip. The only real benefit you're seeing is the fan coming on at an earlier temp and you can get a lower temp fan switch for a fraction of the cost.
Last edited by TA; Dec 3, 2004 at 04:53 PM.
Thread Starter
Drifting
Joined: Oct 2004
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From: Patchogue NY
Yeah, I have to agree with you regarding the hypertech chip. So, I can have the dreaded code eliminated by having a custom chip flashed. Sounds good, glad to hear that. I can not deal with a systems light on while I'm driving. Not acceptable. Thanks for the insight regarding the proper seating of the piggy back chips on the 91. Good looking out.
Thanks,
Joe B.
Thanks,
Joe B.
Race Director
Joined: May 2001
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If I can find the stock 91 program, I'll burn you a custom chip for free. All you'd need to do is spend the $55 on the chip adapter and blank chips from www.moates.net. Send me one of the chips, I'll burn it and mail it back to ya.
IF I can find a stock 91 program.
IF I can find a stock 91 program.
