Popping Sound Please Help Me!!!!!!!

[ilovefords31]

I have 86 300 i6, and I am having a very hard time getting the timing set. The main reason is the timing mark is completely gone so I am trying to time it by ear right now. So I have been turning the distributor a tiny bit at a time, and then test driving. No matter where I put the timing, when I go down a hill and let off the gas pedal, I get a pop, pop, pop, pop, from under the hood, sort of like backfiring. But I only hear it when I let off the gas, but my hearing is not that good so it could be doing it always when I let off the gas, I am not sure. I am really depressed over this because I have nobody that can help me with this kind of thing, and I cant figure out what to do. All the wires and plugs are just over 1 year old, and that is pretty much all ive changed in the ignition system. Please help me!

 

[Beach66Bum]

Hi,

When you turn the distributor Counter Clockwise it retards the timing, and turning it enough in that direction will cause the engine to die. Turning Clockwise advances the timing, and turning it enough in that direction will cause the engine to knock and ping like crazy. With that said, how does it start up? Is the noise more like loud pinging? What's the condition of the exhaust/manifolds? If you rev it in neutral and let off the gas, does it make the sound still? Even worn timing marks can be brought back with a wire brush and then use white out (or such) to paint the faint line back on. I'm sure they're there, just really faint.

 

[ilovefords31]

I have not noticed it while it is idling. It seems to start up pretty good. The sound is like spark knock like out of time knock. One question. There is a notch in the damper. Is that the mark? Also, I was timing it on the drivers side, and since have learned on the internet that I am supposed to use the passengers side? Are you familiar with this? I searched this damper high and low, and cannot find the mark, but like you said it could probably be brought back with a wire brush. See, a while ago I put the magnetic pick up for the timing light on the number 5 wire, and timed it on the drivers side. This was my first time ever using a timing light. I was confused why it was showing the notch on the number 5 wire, and not the number one, but I ignored it. So I have been driving it like that for at least 8 months. It has always made the stutter at lights and idling. Do you think driving it like that all this time could have caused some internal damage?

 

[Beach66Bum]

If you were towing or really beating on it , damage would have occurred but you would have known because you would have had engine breakage internally.

 

[ilovefords31]

amkatt, is it true that the vibration dampers can spin out of place on these engines?

 

[Beach66Bum]

"Spin out of place" ? the harmonic balancer can wear out and become "loose" on the crank, which would require replacement of the part. Grasp the damper and try to see if there is any play/movement,wiggling. Do a visual with the engine running, should be true and no up or down or wobbling. Make sure the bolt that secures it on the crank hasn't become loose and is torqued to specs.

Oh, sorry for the late reply

 

[Beach66Bum]

I have not noticed it while it is idling. It seems to start up pretty good. The sound is like spark knock like out of time knock. One question. There is a notch in the damper. Is that the mark? Also, I was timing it on the drivers side, and since have learned on the internet that I am supposed to use the passengers side? Are you familiar with this? I searched this damper high and low, and cannot find the mark, but like you said it could probably be brought back with a wire brush. See, a while ago I put the magnetic pick up for the timing light on the number 5 wire, and timed it on the drivers side. This was my first time ever using a timing light. I was confused why it was showing the notch on the number 5 wire, and not the number one, but I ignored it. So I have been driving it like that for at least 8 months. It has always made the stutter at lights and idling. Do you think driving it like that all this time could have caused some internal damage?

never answered this,ack! you have to use the passenger side marks, the 300 uses a notch and a saw like gauge that is bolted to the cover for timing of the engine.

 

[5.0Flareside]

X2 on everything Roy has said..

 

[ilovefords31]

Guys, I have something going on that is really aggravating me. I did all the things you all suggested. I Got it timed at 10o btdc and I installed new spark plugs, and new fuel filter, and rebuilt the carburetor, and now the truck runs worse. It is stalling when I come to a stop, and I have the low idle screw all the way in and it barely stays running... as well as it is only running around 500 rpm with the screw all the way in. The instructions on the rebuild kit told me to bottom out the needle valve, then back it off 1 turn. That is way lower then it was when I took the carb apart. It is a carter yfa carb.The float was also way off so I adjusted that to the specs in the kit. What could be going on here? It just wants to stall.

 

[ilovefords31]

I unplugged the tps and the idle went up a little, and now the popping sound, and the stalling when coming to a stop is fixed, but, the idle is still low, and I have the screw all the way in. Does this mean the tps is bad, and would a bad tps do that to the idle?

 

[ilovefords31]

I also have very little power going up hills. I had it floored and only hit 35 going up a moderately steep hill. About 35 degree angle or so. But for some reason it also was not kicking down to second gear, so this was in 3rd gear. Please someone help.

 

[ilovefords31]

bump bumpbump bumpbump bump

 

[Beach66Bum]

hahaha!!! sorry, some of us are drinking tonight

 

[Beach66Bum]

your fuel/air ratio screws should be about 2 1/2 turns out after LIGHTLY seating them, and not more than a 1/4 turn in difference from each other. This is a starting point, use a vacuum gauge to obtain the highest reading. If they're in to far, you will be starving the engine of fuel required and will notice lack of power.

 

[ilovefords31]

Thank you for the advise. I did set the mixture and it still is doing the same thing. Thing is, I don't know where to look. The gasket under the egr spacer probably should be changed, but there is a big tube running from it to the exhaust and I cannot seem to break it loose so I can lift the spacer to put a new gasket in. I know this is a lot to ask, but there are not many who answer questions about my year of truck, so I was wondering if you could answer the following for me?
1. What would make the transmission not kick down when the pedal is at the floor. Kick down rod is adjusted almost all the way toward the throttle.
2. Could any of the symptoms have anything to do with my distributor?
3. How can I tell if the T.P.S is going bad, or failed?

Symptoms
1. While idling the idle is very low, with the low idle screw adjusted all the way in.
2. While idling there is a noticeable skip every 5 or 6 seconds. Adjusting the timing is not taking it out.
3. When letting off the throttle there is a very noticeable backfire in the intake, or exhaust, not sure which.
4. Wants to stall when applying the brakes, and has stalled at stops.
5. cant go over 35 going up a moderately steep hill around 35 deg, incline even floored.
A little history,
The truck was not doing the very low idle, or stalling at stops before I rebuilt the carburetor. I think because I could have the idle a little higher before the rebuild, it was still trying to stall but higher idle kept it from doing so. The only symptom I had before the carb rebuild was the noticeable backfire, and loss of power. I am very grateful to you amkatt. As I stated there are not many who answer about the older trucks, and this is very difficult for me to figure out.

 

[5.0Flareside]

Did you mess with the jets in the carb when you rebuilt it?

 

[ilovefords31]

I unscrewed them and soaked them then reinstalled them. I don't remember if there was 2 or one. I think just one. Also the idle tube. Its a Carter YFA 1bbl

 

[jebadiah04]

I had the 1 barrel carb on my truck, I finally gave in and swapped to the 4 barrel offenhouser intake, and edelbrock carb. I know that's not the only solution out there, but sometimes those old bastard carbs just cant be rebuilt. They are just toooooo old an worn out. With the loss of power you have going on, id say you are either sitting with something wrong with the carb, your timing is off. (don't rule out balancer slipping, mine did) or you may even have a couple spark plug wires off. Also, you might want to spend some time really looking for vacuum leaks, although they usually result in higher idle, id say you have other symptoms pointing at that. If your EGR valve has failed it will act up too. They get old and will let exhaust back into the intake even if unhooked due to a weak diaphragm.

I really cant give you a definite answer without seeing it run, but that is what I can give you for ideas.

 

[ilovefords31]

I had the 1 barrel carb on my truck, I finally gave in and swapped to the 4 barrel offenhouser intake, and edelbrock carb. I know that's not the only solution out there, but sometimes those old bastard carbs just cant be rebuilt. They are just toooooo old an worn out. With the loss of power you have going on, id say you are either sitting with something wrong with the carb, your timing is off. (don't rule out balancer slipping, mine did) or you may even have a couple spark plug wires off. Also, you might want to spend some time really looking for vacuum leaks, although they usually result in higher idle, id say you have other symptoms pointing at that. If your EGR valve has failed it will act up too. They get old and will let exhaust back into the intake even if unhooked due to a weak diaphragm.

I really cant give you a definite answer without seeing it run, but that is what I can give you for ideas.

I truly appreciate the ideas. It has been a while since I looked at this post because nobody has responded to it in a while, but I found out that I have OBD1 on this truck which I was unaware of. I ordered a scan tool for it which will be here tomorrow and I am going to scan for the codes, and then post them in the hopes that someone will be able to help further. I seriously appreciate all the help you have all offered so far, and I hope to be able to post a resolution soon for those out there who may be experiencing these same issues. Thanks again guys and God bless!

 

[jebadiah04]

yes its OBD1, you don't need a scanner to read the codes with OBD1. You can use a test light or a multi meter to read your codes, its pretty easy.


Basically you hook up a test light or meter to the port, then use a jumper to ground out the appropriate port and it should start flashing.