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Discussion Starter · #1 ·
it has a 351w in it, it sat up for a little bit and when I got it, it ran somewhat rough, struggled to stay idling, rough first crank
I replaced fuel filter and spark plugs and it ran the same so I replaced the fuel pump because there was no sock on it and the tank was rusted to hell and back(I cleaned the tank out)
Started it up and it ran the same, 1 week later and it won’t start at all, I am pretty positive it’s a fuel issue since it bogs down when I press the gas
im thinking injectors are clogged so my question is if I use mechanic stethoscope and I turn it over will I be able to hear the injectors?
If y’all have any other ideas of what it could be please help I am stuck and it’s my daily driver
 

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it has a 351w in it, it sat up for a little bit and when I got it, it ran somewhat rough, struggled to stay idling, rough first crank
I replaced fuel filter and spark plugs and it ran the same so I replaced the fuel pump because there was no sock on it and the tank was rusted to hell and back(I cleaned the tank out)
Started it up and it ran the same, 1 week later and it won’t start at all, I am pretty positive it’s a fuel issue since it bogs down when I press the gas
im thinking injectors are clogged so my question is if I use mechanic stethoscope and I turn it over will I be able to hear the injectors?
If y’all have any other ideas of what it could be please help I am stuck and it’s my daily driver
Just go ahead and pull the injectors. You can hook 12V to them to open them and you can rig something up to spray carb cleaner through them. Might want to reverse the flow (spray from the injector tip) to wash any crud out.

Might be time for new injectors.

Not sure about the 351W, but on my 4.6L, I upgraded from the factory EV1 style injectors (which I'm sure your truck has), to Ford Racing EV6 injectors.

Newer style, different spray pattern. Supposed to be more efficient? I dunno. They been in the truck for about 2 years. Better gas mileage than before, but that's mostly because I had a bad injector that I was replacing.



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I would perform a compression test to rule out a mechanical fault.

Also switching to a different style injector probably won’t do much if anything. And if you clean yours do not keep 12v on it for more than a second. They were not designed to have 12v constantly run through them.
 
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I would perform a compression test to rule out a mechanical fault.

Also switching to a different style injector probably won’t do much if anything. And if you clean yours do not keep 12v on it for more than a second. They were not designed to have 12v constantly run through them.
The reason I recommended the Ford Racing EV6 injectors that I linked to is they're very affordable for what they are. A good bit cheaper than OEM injectors and they're still Ford, not some Chinese stuff from Amazon or Ebay.

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Discussion Starter · #6 ·
I would perform a compression test to rule out a mechanical fault.

Also switching to a different style injector probably won’t do much if anything. And if you clean yours do not keep 12v on it for more than a second. They were not designed to have 12v constantly run through them.
Not that I think a different kind of injectors will help but new ones maybe and if I do I might as well get the better than oem ones
 

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Not that I think a different kind of injectors will help but new ones maybe and if I do I might as well get the better than oem ones
That's what my logic was.

They're slightly bigger than stock (24lb vs 19 or 21), but the PCM adapts to it and just lowers the duty cycle of the injectors to maintain the right air/fuel ratio.

Plus, they're Ford Blue :D

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Another thing to consider is that the cats may be clogged up, particularly if they are the originals.
Thats a VERY good point. I had it happen, too. Happened all of the sudden. Driving fine, got on the interstate, gave it some gas and if felt sluggish. About an hour of driving later and I couldn't go over 20MPH WOT. Barely made it back go the house. I can only imagine what the EGTs were like.

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Discussion Starter · #10 ·
That's what my logic was.

They're slightly bigger than stock (24lb vs 19 or 21), but the PCM adapts to it and just lowers the duty cycle of the injectors to maintain the right air/fuel ratio.

Plus, they're Ford Blue :D

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I plan on putting a cam/heads etc so that was my thinking, have room to grow if the stock are already maxed out almost
 

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Discussion Starter · #11 ·
Thats a VERY good point. I had it happen, too. Happened all of the sudden. Driving fine, got on the interstate, gave it some gas and if felt sluggish. About an hour of driving later and I couldn't go over 20MPH WOT. Barely made it back go the house. I can only imagine what the EGTs were like.

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This kinda sounds like my symptoms, I got it running today just checking plugs and filling the gas tank full of gas, it is really low on power, wants to idle around 500-600 rpm and wot is a no go, takes about 4 seconds to kick in and it didn’t go above 3k rpm’s
 

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The reason I recommended the Ford Racing EV6 injectors that I linked to is they're very affordable for what they are. A good bit cheaper than OEM injectors and they're still Ford, not some Chinese stuff from Amazon or Ebay.

Sent from my F-150 using Tapatalk
New injectors may help for sure but like I said they have a different spray pattern that may not be correct for his application.

Not that I think a different kind of injectors will help but new ones maybe and if I do I might as well get the better than oem ones
Like I said above they may help but have a different spray pattern. The original injectors should have a single nozzle where these newer ones may have 2-4. Depending on which direction they spray, they might spray on the walls of intake runners. That will hurt performance because it doesn’t allow for fuel atomization. And if you go with a bigger injector it will run rich on the stock tune.
 
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Discussion Starter · #14 ·
New injectors may help for sure but like I said they have a different spray pattern that may not be correct for his application.



Like I said above they may help but have a different spray pattern. The original injectors should have a single nozzle where these newer ones may have 2-4. Depending on which direction they spray, they might spray on the walls of intake runners. That will hurt performance because it doesn’t allow for fuel atomization. And if you go with a bigger injector it will run rich on the stock tune.
I understand now
 

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New injectors may help for sure but like I said they have a different spray pattern that may not be correct for his application.



Like I said above they may help but have a different spray pattern. The original injectors should have a single nozzle where these newer ones may have 2-4. Depending on which direction they spray, they might spray on the walls of intake runners. That will hurt performance because it doesn’t allow for fuel atomization. And if you go with a bigger injector it will run rich on the stock tune.
Jumping from the stock injectors to the 24Lb EV6 shouldn't hurt performance. Certainly didn't in my case. I went from EV1 injectors in my '99 F150 to the Ford Racing injectors I linked to.

The ECU can correct for the difference in flow fairly easily with a small change in injector size. It's just looking at voltage readings from sensors to get the engine running at it's ideal AFR.

The advantage to the 6 hole nozzle on the injector I'm using is that it does a better job atomizing the fuel.

Frankly, unless it's a race car, I don't think it'll matter too much. The price for those Ford Racing 24Lb injectors is outstanding - that's the main reason I went with them and why I recommend them.

I should also say: unless you get a custom tune for the ECU, every time you unhook the battery, it'll go back to the default tune. As in, any adaptations that the ECU has made to compensate for the changes in injector size, engine wear, altitude, driving style, etc will be reset. It doesn't take long for it to "come back", though.

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Discussion Starter · #16 ·
Jumping from the stock injectors to the 24Lb EV6 shouldn't hurt performance. Certainly didn't in my case. I went from EV1 injectors in my '99 F150 to the Ford Racing injectors I linked to.

The ECU can correct for the difference in flow fairly easily with a small change in injector size. It's just looking at voltage readings from sensors to get the engine running at it's ideal AFR.

The advantage to the 6 hole nozzle on the injector I'm using is that it does a better job atomizing the fuel.

Frankly, unless it's a race car, I don't think it'll matter too much. The price for those Ford Racing 24Lb injectors is outstanding - that's the main reason I went with them and why I recommend them.

I should also say: unless you get a custom tune for the ECU, every time you unhook the battery, it'll go back to the default tune. As in, any adaptations that the ECU has made to compensate for the changes in injector size, engine wear, altitude, driving style, etc will be reset. It doesn't take long for it to "come back", though.

Sent from my F-150 using Tapatalk
I plan on getting the quarter horse shortly bc if I’m not mistaken that saves tunes, and Ik that generally the more holes an injector has the better it vaporizes and normally the least amount of “fluid” you have in the mixture of air/gas runs the best, sorry Im young trying to learn, correct me if I’m wrong
 

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Discussion Starter · #17 ·
Jumping from the stock injectors to the 24Lb EV6 shouldn't hurt performance. Certainly didn't in my case. I went from EV1 injectors in my '99 F150 to the Ford Racing injectors I linked to.

The ECU can correct for the difference in flow fairly easily with a small change in injector size. It's just looking at voltage readings from sensors to get the engine running at it's ideal AFR.

The advantage to the 6 hole nozzle on the injector I'm using is that it does a better job atomizing the fuel.

Frankly, unless it's a race car, I don't think it'll matter too much. The price for those Ford Racing 24Lb injectors is outstanding - that's the main reason I went with them and why I recommend them.

I should also say: unless you get a custom tune for the ECU, every time you unhook the battery, it'll go back to the default tune. As in, any adaptations that the ECU has made to compensate for the changes in injector size, engine wear, altitude, driving style, etc will be reset. It doesn't take long for it to "come back", though.

Sent from my F-150 using Tapatalk
Oh the only thing I didn’t read was where u said it atomizes lol just forget the previous reply
 

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My only warning with tuning is that you CAN mess up the motor. Nothing stopping you from doing something dumb.

That said - read up on it and you aught to be fine.

Seriously READ. Watch videos. Talk to experts. Don't go in blind on your daily driver.

Worst case scenario, you mess up the engine block.

If you have the room and have the ability to swap engines, keep an eye out for a 351W for sale on Craigslist or Marketplace. If it's a good deal, pick it up as a spare so if you mess up your engine, you aren't without a truck for too long.

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Discussion Starter · #19 ·
Jumping from the stock injectors to the 24Lb EV6 shouldn't hurt performance. Certainly didn't in my case. I went from EV1 injectors in my '99 F150 to the Ford Racing injectors I linked to.

The ECU can correct for the difference in flow fairly easily with a small change in injector size. It's just looking at voltage readings from sensors to get the engine running at it's ideal AFR.

The advantage to the 6 hole nozzle on the injector I'm using is that it does a better job atomizing the fuel.

Frankly, unless it's a race car, I don't think it'll matter too much. The price for those Ford Racing 24Lb injectors is outstanding - that's the main reason I went with them and why I recommend them.

I should also say: unless you get a custom tune for the ECU, every time you unhook the battery, it'll go back to the default tune. As in, any adaptations that the ECU has made to compensate for the changes in injector size, engine wear, altitude, driving style, etc will be reset. It doesn't take long for it to "come back", though.

Sent from my F-150 using Tapatalk
I found ev1 style injectors for the mustang that’ll fit the 351w, they flow at 24 lbs, for $100? Are they worth buying or for the price do u think they would go bad in a couple months? They
My only warning with tuning is that you CAN mess up the motor. Nothing stopping you from doing something dumb.

That said - read up on it and you aught to be fine.

Seriously READ. Watch videos. Talk to experts. Don't go in blind on your daily driver.

Worst case scenario, you mess up the engine block.

If you have the room and have the ability to swap engines, keep an eye out for a 351W for sale on Craigslist or Marketplace. If it's a good deal, pick it up as a spare so if you mess up your engine, you aren't without a truck for too long.

Sent from my F-150 using Tapatalk
im trying to find a class on tuning rn, I wouldn’t tune it myself until I know for a fact that I can, Thankyou for the advice, I think I’m gonna check timing, make sure all 8 plugs are firing and then move to cleaning injectors
 

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Jumping from the stock injectors to the 24Lb EV6 shouldn't hurt performance. Certainly didn't in my case. I went from EV1 injectors in my '99 F150 to the Ford Racing injectors I linked to.

The ECU can correct for the difference in flow fairly easily with a small change in injector size. It's just looking at voltage readings from sensors to get the engine running at it's ideal AFR.

The advantage to the 6 hole nozzle on the injector I'm using is that it does a better job atomizing the fuel.

Frankly, unless it's a race car, I don't think it'll matter too much. The price for those Ford Racing 24Lb injectors is outstanding - that's the main reason I went with them and why I recommend them.

I should also say: unless you get a custom tune for the ECU, every time you unhook the battery, it'll go back to the default tune. As in, any adaptations that the ECU has made to compensate for the changes in injector size, engine wear, altitude, driving style, etc will be reset. It doesn't take long for it to "come back", though.

Sent from my F-150 using Tapatalk
Apples to oranges, injector placement is different which affects both differently. Can the 6 hole injectors atomize fuel better, perhaps, but even so it’s negligable at best, especially in the older pushrod motor.

Also, the ecu will not be able to adjust to the bigger injectors. The ecu expects x amount of fuel given a pulse. With bigger injectors more fuel is injected given the same pulse time. The ecu cannot adapt to the difference in fuel flow and will run rich. This is evident in the mustang world when Ford switched from 19 to 21 pound injectors in late 01. The model years with the 21 pound injectors ran rich in stock form because Ford did not adjust the tune.
 
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