on my 03 Ex 4.6l. I've posted before about a suspicious O2 reading I get only on one side (driver) that shows a lazy 02 that seems to want to show a rich reading (.6-.7). I've swapped and replaced both 02's with new bosch sensors and I get the same reading from the upstream drivers side. I'm wondering if I have a leaky injector on that side.

Not sure how to test for that other than to pull each plug and look for carbon buildup more so one one plug than the others. Is there a better way to check for leaking injectors?

And if I find one that looks suspect, can it be serviced or do I need to replace it. And of course, I'm wondering if I do need to replace it, how do I get it out. Can anyone offer a simplified procedure for taking out the injector(s)?

Thanks.

 

If you have a fuel pressure guage, you can hook it up to the fuel rail and check the reading after shutting down the engine. It should hold the pressure.

To remove a fuel injector, you must remove the fuel rail on the side that the suspect injector is on. The fuel rail is held in place by 2 screws. The screws are screwed into the intake manifold. Once you've removed the 2 screws, you lift up on the fuel rail and out pop the injectors. There's no need to remove the fuel rail completely. Only need to lift it about 3-4 inches. When you remove the injector, make certain that the upper O ring comes with it. These sometimes remain inside the fuel rail. If they do, use a small screwdriver to remove them from it.

Unfortunately though, I would venture to say that it's not your injectors as they rarely go bad.

Good luck

Anthony

 

have u had them flushed?? or had an injector leak down test done.. if there is debris in there then it will stick an injector open

 

How do you know that it's running .6-.7

 

No tests done of any kind thus far. Just fishing for ideas before I go spending money on a "test" that I didn't need. I'm just trying to figure out why my O2, even after being replaced would show a sluggish reponse and a reading that tends to hover around .6-.7.

As for how I know the reading, it is from the datalogging in Xcal. The graph does go up and down, but slowly. Doesn't switch fast like the other O2 (which is the way it should). And the intermediate values of the bad O2 seem to fall in that range.

here is the graph from my gallery - third graph down (red) is the questionable O2. 2nd graph down from the top (black) is the good O2 (psg side).



Just trying to figure out why only one side would tend to show a rich reading and show a lazy response, even with swapping original O2's and two new replacements. I should add that the truck runs like a top. No problems, no codes, no CEL's. Just thinking I am using more fuel on that side for some reason.

Any thoughts?

 

My recommendations: The engine will throw a code if there's a problem. I think you need to park the Xcal and quit worrying about it. If there isn't a code, then the rich condition and the slow switchrate are within spec. Any attempts to change the fact will probably be met with dissapointment, because according to the logic of the computer, everything is fine.

Now as for an explanation.. I can't read the graph, so are you sure you're monitoring the FRONT o2 sensor? A rear O2 sensor will switch slower by nature. Also, O2 sensors AREN'T the most exact at determining a/f ratio. So, instead of buying more sensors/parts, go buy a wideband and see what's going on. Also, you could be having a ground issue that the Xcal is seeing. I don't know how the edge hooks to the O2's and I don't know how the Xcal is grounded, but that is a common problem.

I can't think of any more reasons right now, but if it were me, I'd just leave it alone. The switch rate is in spec, and the a/f is in spec.

Thought of something else. AGAIN, I don't know how the Xcal works so this might be a stupid suggestion, but try datalogging JUST the faulty O2 sensor. The Xcal may be getting interference between the two.....

 

Thank you Chester. I agree about the no CEL / code perspective. Just part of my personality that likes to tinker and find out "why". As for the O2, Im sure that I'm sure that I have the right ones identified. the datalogging software is very clear in lableing which is which. I've logged both front and rears.

I was thinking about a ground issue too. Didn't think about it in the Xcal. was thinking about the wiring in the truck somewhere. That might be a little too much digging even for me, unless it throws a code.

I may still check the plugs. Its something I can do in my drivway that wont' hurt anything.

PS - where would one install the wideband sensor?