Help with Backfiring!
Gents,
Chris here! New to the forum. I just bought a 87 Ram with a 318 in it. Truck is clean and run ok except for the following:
It idles fine but every once in a while, you can hear a little "pop" out of the right bank exhaust. ( has duals on it) If I rev it, it backfires pretty bad. The truck doesnt seem to have as much power as it should... its sluggish. If I am driving and climbing a hilloron the highway andlet off of the gas, it backfires pretty badas well. Any suggestions? The motor was tuned up just before I bought it. I can hear a slight exhaust leak so I thought that maybethe leak was sucking air upon decceleration. I am new tothe 1st genDodge so any advice would be greatly appreciated. Oh, the motorhas 140,000 miles on the clock... timing chain maybe?
Thanks,
Chris
Chris here! New to the forum. I just bought a 87 Ram with a 318 in it. Truck is clean and run ok except for the following:
It idles fine but every once in a while, you can hear a little "pop" out of the right bank exhaust. ( has duals on it) If I rev it, it backfires pretty bad. The truck doesnt seem to have as much power as it should... its sluggish. If I am driving and climbing a hilloron the highway andlet off of the gas, it backfires pretty badas well. Any suggestions? The motor was tuned up just before I bought it. I can hear a slight exhaust leak so I thought that maybethe leak was sucking air upon decceleration. I am new tothe 1st genDodge so any advice would be greatly appreciated. Oh, the motorhas 140,000 miles on the clock... timing chain maybe?
Thanks,
Chris
Most often a backfire is the result of an air leak in the exhaust system. For a moment when you up shift and often when you let off the gas, there is a temorary "over rich" condition with too much gas in the cylinders. This blows into the exhaust and if there is oxygen (air leak) then it explodes in the hot exhaust pipe. Without the air leak, it is cooled enough not to explode by the time it reaches the atmosphere in a tight exhaust.
Look at the exhaust system and repair any problems. Also make sure that the carb is adjusted for good running and fuel economy otherwise.
1. check the carb. try to set it lower for the fuel
2. check see if you have a bad spark plug that not firing off
3. can be the spark plug wires may have a bad one
hope this helps you out.
what is the problem of backfiring can be like 11 diff. things that can cause it.
but only listed like the top 3 problems can be.
Look at the exhaust system and repair any problems. Also make sure that the carb is adjusted for good running and fuel economy otherwise.
1. check the carb. try to set it lower for the fuel
2. check see if you have a bad spark plug that not firing off
3. can be the spark plug wires may have a bad one
hope this helps you out.
what is the problem of backfiring can be like 11 diff. things that can cause it.
but only listed like the top 3 problems can be.
I have now found out that the exhaust is leaking pretty bad... I heard it yesterday morning. I did change the spark plugs on Saturday. 7 out of 8 spark plugs were the normal brownish-white color except for rear cylinder on passenger's side of motor. It was black. I am thinking that thatspark plug wire is smoked... not firing. Cause of no power and backfiring too?MAYBE....
I really didnt want to play with the carb because of the old plugs being so clean. I think the fuel mixture is set pretty decent. These trucks dont have an ECM right?Wasnt sure. I know that my distributor does not have a vaccum advance on it so Iassumed that it was controlled electronically? Someone told me that these things are notorious for 2 things: bad distributors andburning out exhaust valves. Could this be the problem as well. Someone just sell me a nice built up 318 that I can through in this thing! 
Chris
I really didnt want to play with the carb because of the old plugs being so clean. I think the fuel mixture is set pretty decent. These trucks dont have an ECM right?Wasnt sure. I know that my distributor does not have a vaccum advance on it so Iassumed that it was controlled electronically? Someone told me that these things are notorious for 2 things: bad distributors andburning out exhaust valves. Could this be the problem as well. Someone just sell me a nice built up 318 that I can through in this thing! 
Chris
In all the time i've worked on anything. It's always do it the simple fixes first. you were right to change the plugs. i would go ahead and give it a full tune up for the fact you know it's had one 100%. not sayin the person lied to you but you never know. I would change plugs wires cap rotor air filter fuel filter and go ahead and give the old girl an oil change too. After you fix the exhaust of course. If that doesn't work then check the timing. then go ahead and look to the carb if all that fails. After all the above is said and done the truck should run great.



