Engine Carbed 5.0 swapped run like chit.

JMO
Those plugs actually look pretty good, maybe a touch lean for a carbed car, I think your problem is electrical, voltage at coil or the fuel pump may be dropping.
I thought so too.. but on another note as far as those looking a tad lean, the car since i got it has been unbearable to stand near or even have the door open while running(it has dumps) because the smell of unburnt fuel has been so strong. So I always figured it was a bit too rich. But since it started running like crap i leaned out the carb about 1.5 turns or so and it only was run leaned out like that for the 30mins or so.. not sure if that amount of run time could change what the plugs look like but figured id mention it.. and ok so how do i go about testing those? Also the fuel pump is a newish holly inline pump.. i wasnt the one to hook it up and dont know a ton about them but it looks like its spliced into the stock fuel pump meaning it pulls through the original pump and pickup, at least thats what it looks to me, as i can see the holly pump just outside the tank attached to the original line.
 
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Digital volt meter, measure the volts to the pump, you are looking for a voltage drop as the pump runs starting at first start and continue to monitor volts through engine warm up, also touch the pump to feel how hot it gets.
Same with power wires to coil, just don't touch the coil, it will bite you. Seriously, I'd rather be btch slapped by Conor McGregor
 
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Digital volt meter, measure the volts to the pump, you are looking for a voltage drop as the pump runs starting at first start and continue to monitor volts through engine warm up, also touch the pump to feel how hot it gets.
Same with power wires to coil, just don't touch the coil, it will bite you. Seriously, I'd rather be btch slapped by Conor McGregor
So far i still have not been able to test either of these things as ive been busy with the front end of the car taken apart. But also i cant even have the car running long enough to test these things.. it starts up at like 1500rpm n then to 700 and drops dead every time. Runs for about 10 seconds..
 
So far i still have not been able to test either of these things as ive been busy with the front end of the car taken apart. But also i cant even have the car running long enough to test these things.. it starts up at like 1500rpm n then to 700 and drops dead every time. Runs for about 10 seconds..
Also I’ll add i have the fuel pump hooked up to a switch, so i turn the switch on when im ready to start the car.. i can hear it when the car is off and it sounds the same as it always has, not that it means anything. But i just cant get the thing to run long enough to test anything..
 
Digital volt meter, measure the volts to the pump, you are looking for a voltage drop as the pump runs starting at first start and continue to monitor volts through engine warm up, also touch the pump to feel how hot it gets.
Same with power wires to coil, just don't touch the coil, it will bite you. Seriously, I'd rather be btch slapped by Conor McGregor
Ok i finally got the car to run long enough to run and test the power wires connected to the coil (msd blaster ss), and it read about 5volts idle at about 5-600rpm,not sure what volts its suppose to be but im guessing its suppose to be higher than that.. and then it starts idling down and stalls and the volts go:5-4-2-0..
 
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You should have 12 volts at the red/green wire at the coil.
I just had help testing it again, with a different volt meter and it read NEGATIVE .678 im quite puzzled.. be in mind the coil is powered from the msd6al box, im unsure if the power would read differently from that but yea.. also sometimes like right now, i start the car up and it runs enough to stay running for any amount of time as long as i dont touch the gas.. but it sounds like it has a miss fire to me because it just dont sound right lol.
 
Ok you lost me there, I'd have to be there to help ya, sorry.
Should i have power at the coil with just ignition turned on? Because while the car isnt running i have no power..
Edit: well i did some research and on the msd tech help site they say that there should NOT be any voltage to the coil without the engine running. And also, while running there can be upward of 350volts and fluctuations.. i read with another meter that it was at 5-35volts fluctuating so idk anymore.. im frustrated
 
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Ok so i did hours of research so i could hopefully find the root of my problem tomorrow.. what ive come up with is that the coil itself has gone bad, ive decided this is the most likely problem because my engine seems to be having very similar problems that other people have had due to a bad coil. As well as 100’s of people having this same issue with MSD specifically their made in china crap coils. Many stories of them dying in 3-6 months and some lasting a couple years.. mine is about 2-3 years old but has barely any time on it so i wouldnt have given it a second thought, but now im quite sure this could be the issue. Tomorrow i will be doing a ohm test on it and probably switching to an accel super stock coil.. it sounds as though a stock motorcraft coil is your best bet, but as i have an msd6al im unsure if i should use that or if its possible.. i will confirm or deny whether or not this was the issue for anyone in the future when i get down to it..
 
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Put a Ford coil on it.
I did exactly this, expecting to fix my problem of course. Andddd nope it still runs like chit, no change at all. So im back to not knowing again. I took apart my ground leads and cleaned corrosion off and still nothing. Tested all my plug wires and they seem fine. The last thing i can think of is the carb got too much chit in it so I’ll probably take it off and clean it.. doubt that will do anything but who knows. Back to square 1 but i know whats not the issue now!
 
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Ok so i took off the carb and took some parts of it apart but didnt do a complete breakdown because it looked pretty stinkin clean in there as it should, but i cleaned it pretty good and i even found a spidey sorta blocking some jet hole on top under the air cleaner idk what hole but yea. And did all that got some cleaner in my eye (how long before i learn?) and slapped her back on and it still runs about the same im unsure if anything changed.. still sounds wrong like a missfire and wants to die after throttle half the time.. also i checked the timing to make sure it didnt jump somehow, and it was in range.. im fresh out of ideas.. i guess I’ll pick up some plugs tomorrow just so im sure thats not the issue, and drain the tank n put some new gas in it and see what i get.. other than that please help lol.
 
Grab a vacuum gauge, check vacuum readings,
Does you distributor have vacuum advance?
I have to go back and refresh what been done and what is happening.
I wish I could put hands on this thing, I feel we are missing something.
 
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Lets see how it runs with new plugs.
After going back over your thread I'm back to an electrical issue.
Here is something to try, after you change the plugs and it still is not right, when it is running and starts to die, either spray starting fluid in the carb or close the choke and see if it picks up.
 
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Grab a vacuum gauge, check vacuum readings,
Does you distributor have vacuum advance?
I have to go back and refresh what been done and what is happening.
I wish I could put hands on this thing, I feel we are missing something.
How do i check vacuum readings? Ive never done something like that before unfortunately.. and i dont believe it does, i dont recall any vacuum lines going to it.. it is a msd dist some sort of billit one i cant remember the pn Ill check tomorrow. I wish you could too because i feel the same..
 
Lets see how it runs with new plugs.
After going back over your thread I'm back to an electrical issue.
Here is something to try, after you change the plugs and it still is not right, when it is running and starts to die, either spray starting fluid in the carb or close the choke and see if it picks up.
Ok will do..thank you. Also I have stock truck heads i think, and have autolite 25’s they are just copper core standard. Is it worth the extra buck each to get the autolite ap25 platinum?
 
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Also i been wonderin maybe because its been cold and the car been sittin a lifter got stuck?? Not sure if it would cause these problems.. but i do notice on the driverside it sounds like somthing is goin on not sure..