Contour Enthusiasts Group Archives Forums Modifications 3.0L Duratec Injectors?

I am only wondering since I can get FRPP parts for a discount..but I wont do the leg work if the demand isnt there... If people are satisfied with getting used ones, then so be it. I will have to decide which ones to go with on my car...and whether or not to use 19lb or 24lb on my 2.5L engine....

Nikolas

I would be interested in getting new 24's to fit the returnless system, I'm just trying to figure out what is compatible at this point.
Fordpartsonline lists the 99 Taurus injectors that Brad had at $40.xx but the 00/01 units at $27.xx - maybe Bill Jenkins can straighten it out.

i ahve 24lb injectors off a 01' 3L with 4 miles

Do they have the right connectors to fit the returnless system? If so, I'd be interested in them.

I got the driveability issues once the exhaust went on. Stock pressure.
I tested by raising the stock pressure again, and that seemed to help for about 10 minutes. At that point the cpu learned about the new fuel pressure and the 'stuttering' came back though not as bad.

I have the new fuel pump and I am waiting on the new MAF as well. I will update you guys after I put on the new MAF. I may still end up with bigger injectors in the long run.
Brad, can you get 24# injectors that fit? Cheap?
If so, maybe we can do some swappage. I've got 3L heads and some other stuff.

warmonger

The engine gets more fuel with the same size line by running a higher pressure. The stock 2.5L engine runs at 39psi idle and 45 psi WOT whereas the SVT's run at 45 psi idle and 54-55psi WOT. The higher pressure just means more volume of fuel per unit time.

warmonger

well i haven't taken a look at the connectors but i am assuming that they do. If anyone can chime in please do

The 24's I've had came off of 3 liters that I've purchased. None available at this time. You need to get that thing on a scanner with a wide band O2 sensor if it's having stutter problems.

Also, the ECU wouldn't be able to learn anything about higher pressure in the fuel line as it doesn't use the O2 readings at WOT... Not sure why the stutter went away and came back... having trouble figuring that one out. BTW, how did you jump the pressure?

What I meant about the pcm 'learning' the pressure:
The key about the pcm learning the high pressure is the way I jumbed the pressure. I fixed it to the desired pressure with a screw. This prevented the two-step pressure that the regulator normally has (45psi idle 54psiWOT). Initially it helped out, but as the pcm corrected the normal non-WOT driving to the high pressure it began to stutter again. I am convinced that the pcm made adjustments to WOT injection because when I would step on it, I would get some pinging up around 6500 rpm that was not there when I had the "two-step" fuel pressure. The pcm definitely counts on the pressure jump when you go WOT, I've proven that to myself on numerous occasions.

Now all that said, I haven't gotten any new O2 data with the new exhaust. However, I got enough data before to extrapolate what is going on.
Essentially, with stock intake and exhaust I had no driveability issues, but the O2 data showed that my AF was already lean below the IMRC opening point, then at that point the AF went from lean to a little too rich.
When I fixed the pressure with a screw, this had the effect of leaning out the AF above the IMRC point because it didn't have the 2-step change in pressure. That leaning out evidently put me in the right AF value for that rpm range because I had lots more power.

With the exhaust down at the y-pipe on the dyno:
The AF ratio for the whole rpm range just got leaner by a few points, but had the same overall shape. I lost torque below IMRC point because it was way too lean at that point, but the AF ratio was pretty good above the IMRC point and that is where I made so much power.

So here I am with the open exhaust having a product of those problems. I am too lean below the IMRC point and pretty good above the IMRC point. THerefore I get a lot of power above and stuttering below.

So how do I fix the problem?
Maybe an SAFC, but the new MAF is going on first.
If the MAF has no effect then I will have to go get an SAFC.
I'm really tired of waiting though.

warmonger

At part throttle, the new MAF or S-afc won't do anything because the ECU will relearn everything to get back to within stock specs. WOT is another matter.

The ECU ignores the O2's at WOT and bases the fuel and timing off of the MAF values vs. RPM on a preset table. Changing injectors, MAF's, and MAF values (via S-AFC, Calibrator, or the MAF itself) will have a profound effect because the ECU will not relearn these preset tables. If that is where your stuttering problem is, you could be in luck.

It's all good, what's it hurt to try, right?

Forgot to mention... at 212 to the wheels, you are very close to 100% duty cycle, at least by doing the math. Any OBD-II scans at WOT?