Backfiring after JC chip install
- Thread starter bichmgnt
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I have no idea why your car would backfire after installation of a Jim C chip? I assume that this condition had not manifest itself piror to the installation? I would contact my supplier and see what they offer.
The rally cars that "backfire" on every corner are not backfiring as in this case. What you are seeing is unburnt raw fuel being ignited and burned by the heat from the exhaust, when the car decelerates.
The rally cars that "backfire" on every corner are not backfiring as in this case. What you are seeing is unburnt raw fuel being ignited and burned by the heat from the exhaust, when the car decelerates.
If nothing else was touched, I would first double check the ECU number for the right chip. There are several different chips depending on the year ECU. Reinstall stock chip. If it runs better then I would call the vendor, explain the problem, and they may have encountered this before and can tell you the solution. They will also offer to send you a new chip with return of the old one. The program has not been changed and has been around for years. The chips are waranteed for life and the vendor (Turner Motorsport in my case) will offer to replace it at no charge or offer you a refund. I have the JC chip in my '89 for over a year with no such problem. My problem is the 91 octane gas I have here. It is not high enough for summer performance driving. I run a 25% mix of unleaded 100 octane for the summer for best performance.
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I guess this is more of the couple quick pops rather than a loud and severe backfire. But aren't these pops backfires? That's what I'm concerned about. It's never done this before. I am running 91 premium and it's the right chip for the ECU. New plugs, new timing belt, valves just got adjusted all just before installing the chip.
Should I be concerned?
Steve
Should I be concerned?
Steve
You could either have an exhaust leak or an intake leak. It's just a thought. Sometimes air into the exhaust tract will cause backfiring.
Rally cars backfire because they are sometimes equipped with anti-lag which is a severe ignition retard combined with a fuel injection into the intake tract. The engine management commands the injector to fire when the gas pedal is release to keep the turbo spooling when the foot is off the gas. It's an effective way to build boost pressure for quick corner exits .
Rally cars backfire because they are sometimes equipped with anti-lag which is a severe ignition retard combined with a fuel injection into the intake tract. The engine management commands the injector to fire when the gas pedal is release to keep the turbo spooling when the foot is off the gas. It's an effective way to build boost pressure for quick corner exits .
If you are encountering high temps in CA try adding 3 or 4 gals of unleaded 100 gas. The JC chip calls for a minimum 91 octane but that is insufficient if you run air temperatures like we do here in summer. I would still give the vendor a call. It can help eliminate potential areas to investigate. Like others have said, it may mean nothing but why take the chance.