It's your money. You say to replace them as cleaning is a waste. For less than the price of one injector, I have had mine working like new when before the truck was sluggish. Cleaning does work and make a difference. The book states that you do not need to add anything to the fuel. It does not say don't clean the injectors. Which was done by the dealer in my case.

So far I have had 4 trucks with injectors and put a total of 400,000 miles on them. 160k on one alone. Never have I had to replace an injector. Cleaned multiple times, but never replaced.

 

 

No, I said don't replace them, AND don't clean them. I'm saying that they DON'T sludge up because 1. there's nothing in today's gasoline to make them sludge in the first place! 2. If there was, then why don't your fuel lines "sludge" shut? 3. Why don't the fuel filter holes "sludge" closed? 4. What about the injector screens? Why aren't they stopped up with "sludge"? That's because there isn't any sludge in it at all! Shellac is a thing of the past, that was attributed to carbureator deposits due to evaporation.

5. You'll get a CEL when an injector stops up.

But that being said, do whatever makes you happy. It doesn't really matter about the truck, as long as you sleep good at night!

 

How much ARE a set of nicer fuel injectors...and how are they rated (like the number towards what they perform better at)??
~Phil

 

Unless your truck has some serious mods, or a weird problem, the stock ones will perform the best.

 

O.K. cool! What if I want to change them to gain performance? What would I have to do in order to have the mod's needed to change them to a higher performance?? Thanks agian for clearing it up
~Phil

 

You would have to have enough engine mods to "max out" your injector's flow capabilities. And even then, there's cheaper ways to get more flow out of your injectors. In short, unless you're running some type of forced induction, you probably won't max the stock injectors out.

What modifications do you have in mind?

 

Chester; perhaps you had better go do some homework. The computer does not have any idea if an injector has fired properly or not; All it knows is that the injector has constant power, and is grounded to be opened. If those two things happen, the PCM assumes the injector is working correctly. Fuel lines don't get varnished, or 'sludged' as you put it, because their always full of fuel! The absence of fuel on an injector for the 1/100th of a second over a few years WILL cause varnish, no matter how you look at it. Why do you think fuel tanks rot out? Filter screens are just that- Filters. They ARE serviced in any good shop, and any GOOD technician knows this.

The best way to get more power, is to give the vehicle more fuel. Whether it's higher fuel pressure or more volume, That's the key. So Stock injectors are not the best for power/performance. Plugging the pressure regulators vacuum supply will yield 10 PSI more pressure, therefore improving power, but drastically reducing fuel economy. The injectors on Ford vehicles from about '97 to present are of the saturated style. They are synchronus, which means they are timed to the ignition, or the event. (spark, squirt)

Besides a tuning chip, or a tuner program, the best bang for buck is fuel delivery for performance.

 

Interesting. Read post # 6 in the thread below.

https://www.f150online.com/forums/sh...d.php?t=276882

 

The computer knows if an injector sprayed or not through information gained from the missfire monitor. I don't feel like writing an essay today on how it works. But put it simply, if you had a stopped up injector, that particular compression stroke would not yield the "correct" crankshaft acceleration, and that would be detected by the missfire monitor.

Bluegrass knows his stuff. Read the post that oneloaf gave you.

I don't necessairly agree with this statement ..But I don't have time to argue it right now. I don't see bigger injectors helping anything until you have a need for them. It's not a diesel.

 

You can gain a little torque with them.

Read post #9 in the post below.

https://www.f150online.com/forums/sh...d.php?t=273321

 

hey 94 f150 i have an 88 and i didnt have the bucks for the injectors when i built the motor so i stayed with the 19lbs stock ones, if i put a plug on the fuel pressure regulator i will be flowing as if i had got the 24pounders?? or at least close to it?? do you think that is worth the loss of mpg?

 

Well remember that there's no replacement for displacement - a bigger pintle is a bigger pintle, regardless. But yes, plugging the Regulator vaccum line will not control fuel pressure, resulting in higher output pressure from the pump - Approximately 10psi. Kind of a backyard trick, but it works - but you'll be giving up economy, remember. Just try it, See if you like it. It's completely reversible. For that stock look, I've used a ball bearing pushed up inside, and then you can just put the hose back on. If you just want to try it, Use a Golf Tee.

-Jimi

 

freakin awsome i love tricks like that! thanks!

 

Well you guys are beginning to spar and get out in left field a bit.
Injectors are sized to fuel the HP the engine is designed to produce.
Just replacing with larger capacity units dosn't increase power. Only with diesels can you do that.
The why of it is simple when you take into account that no more air is used to make more power. At less than WOT the ox sensors keep an A/F ratio at 14.6 to 1, so incressing the injector size or raising the fuel pressure just makes the PCM shut them down more when the OX sensors detect the extra richeness.
At WOT. the best A/F around 12 to 13 to 1 gets too rich again and 'may' reduce power for no other reason and burn more fuel.
Another thing you can get into with injectors to big is the min and max. opening pulsewidths are taken out of proper design limits.
A bigger injector flowing to much fuel is shut down below it's min reliable fuel metering then metering become non-linear while the max power pulsewidths are operated off fixed tables in the PCM and not the OX sensors. This in itself can make WOT fueling too rich because the PCM does not know anything about the injector "size", only that something is there by electrical monitors.
The miss fire detectors don't have much to do with the injectors directly.
The missfire monitor detects the time of the power stroke and detects it as a missfire if it become to slow when compaired to internal PCM history and expected times. When the power contribution is down, the monitor assumes the cylinder is missfiring for whatever reason, a bad plug, COP, boot, plug wire, coil module, injector, water in the fuel or anything that interfers with combustion. It can't tell what the 'exact' cause is.

As for injector spray patterns changing over time. It's common knowledge that over time the patterns can change from seat wear, carbon formations on the tips, gum from a leaking injector, acids in the gas that will still flow by a filter, crank case oil intake from the PCV, engine cylinders that stop with the intake valve open exposing the injector to heat before cool down and sometimes reversion flow back out of the cylinder. This is how the under sides of an intake valve can carbon up. It's also part the temp of the parts where a cooler surface can collect these things. Over time, carbon can soak up part of the injector flow and never reach the cylinder.
Mass Air control can account for a lot before it gets to far out of hand but Speed Density engine control cannot account for these things very well because the engine is running on a computer model program that can't account for some things because it has no way to do so..
So bottom line is, in the real world, injectors do go 'south' over time for several reasons. You may never feel it because there is nothing to 'constantly' compair with until they are ether cleaned, fail in some manner or replaced. While this is all going on, the PCM program can in most cases correct for poor operation by up to 20%. This keeps you from feeling the effects until the program can't correct any futher.
The old carbed engines suffered from poor valve seal when aged, become hard starting etc. Notice nobody complains about needing a valve job any more because FI covers it up until they get so bad the power takes dive.
The valve seal lasts so long now because of the precision of fuel injection and the cooling the intake valve gets and the much better condtions the exhaust valves have to live in.
Ahh, computer programs that learn until their limits are reached!