Answer: If EGR passages to the intake are blocked, it can cause backfire with the increase in cylinders temperature. Cranks but no start, backfiring through intake. But if i shut it off and start it a few time it will get better. the only problem it has is popping/backfire while cranking. backfire is a result of half burned, hot exhaust finding oxygen to finish burning. Photo courtesy of Love Krittaya on Wikimedia. This can occur due to a faulty intake valve or intake manifold that's causing extra air to leak into the system. Then when I tried to start it,it backfired through the intake. i can supply video upon request or send link to video. One is to buy and keep it for years hoping that the price increases, the other is to buy for a low price and flip it for a quick profit. A basic knowledge on the electronic fuel injection system eliminates the guesswork in the calibration of LPG-powered cars. With erratic ignition, if the spark does come, can come at any time, even the wrong time, and if the intake valve is opened, it will backfire. Dan Ferrell (author) on November 25, 2019: You may want to try checking the catalytic converter. ... You may have to open the engine and use a micrometer to check the camshaft lobes for wear. The problem could be in a number of systems, specially the fuel or ignition system. There is often a backfire or two when this happens. Answer: Check the fuel pressure, then check the ignition timing and ignition system, in that order. The computer may have one or more pending codes that could give you a clue about a potential system involved in the problem. A strong backfire can damage gaskets, sensors, valves, and even a plastic intake manifold. For an engine to backfire through the intake, the intake valve must be open at the time the air/fuel mixture ignites. Also check the carburetor mixture adjustments. Answer: The problem could be in the fuel system. Consult your repair manual for the correct system pressure for your application. One type of backfire that occurs in a 23 HP Kawasaki engine is caused by improper ignition timing. What was wrong exactly, with your new stator? Try downloading trouble codes, even if you don't see the check engine light lit. Answer: Make sure to check for trouble codes, even if the check engine light is not on. Question: I have a 1996 Chevy Silverado 1500. They could give you a clue about where to start diagnosing. Answer: There could be several possibilities, and yes, the timing could be one of them. It was running awesome you guys, I had it out 3 times with new carb set-up and had just got the kinks out. Also, some vehicles models are equipped with an air injection system. It goes away at a higher speed above 40mph and up. I just replaced the fuel filter. Dan Ferrell writes about do-it-yourself car maintenance and repair. Download trouble codes, even if the check engine light is not on. Answer: It seems like a faulty sensor's coil. You don't need a lot of money to start selling classic cars, you just need to buy the first car at a good price and then do it again. Backfires when accelerating. Put a clean small screwdriver into the spark plug opening so you can tell when the piston is at the top of the stroke. A pending code from a sensor can guide to the problem area. Backfire is a condition described as a loud bang, poof, explosion, etc., while the engine is running or while shutting down. The EGR valve opens when engine speed increases and closes when engine is resting at idle. A sticking-open valve can cause a backfire. These are the most common issues. Answer: Check EGR valve operation; make sure the valves are opening and closing properly. Also, make sure there's good spark. Im supposed to be working on my BB558, not this one! Suggestions? What happens behind the scenes will shock you. Though, it can also happen when turning off the engine or when slowing down. So paying attention to regular maintenance items in key systems like fuel, ignition and emissions can go a long way in keeping your vehicle running in top shape. The vehicle backfires at 40mph and will not go over that speed, acceleration and deceleration are perfect, lots of power but just stops at 40 mph with backfiring. Replacing the plugs, boots and seals was probably a good idea; still there might be other problems. I turned up the idle screw a bit and it stopped backfiring, unless you tried to choke it, then it would backfire. Its pointing towards a timing issue to me, thought I may have bent the valves while changing starter clutch, but I have a remover tool and a big electric impact wrench, it removes the nut with very little torsion and the actual clutch comes off with no torsion at all. Remove the spark plug(s) from the engine . Question: For my 1997 Grand Cherokee, can a backfire be caused by a clogged catalytic converter? If a sensor fails to send the correct signal, the computer may deliver too little fuel, creating a lean fuel condition. I can let go of the throttle and it'll settle back to idling. And whenever you encounter a backfire, this guide will help you trace the culprit.