Fuel injector expected lifespan?

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No. Actually, as far as I can see...which is somewhat restricted by

*this and that,* it appears that the fuel line goes to the injector rails, actually the rails appear to be connected with some kind of flexible fuel tubing.

I would like to spend more time under the hood examining this. I was only out in the driveway for 10 minutes, and was getting dirty looks because I was holding up dinner.

Of course, yes.

good question. Like I said above, I would like more time to look at this.

OK, that I believe. It is a squarish module attached directly to the bank 2 fuel rail, and has a wiring harness and vacuum line going to it.

So I still have a question then. The vacuum to the sensor appears to move according to the demand for fuel via the throttle position. IOW, if you *goose* the throttle plate for more rpm's, I get a larger vacuum...say 20mm Hg...and when I let the throttle snap back to the idle position it falls to 10mm Hg, and then stabilizes at about 15mm Hg.

So there is _some_ interplay between intake manifold vacuum, and this

*module.* IF this was just a pressure sensor, as in say, a coolant temp sensor, or say ... an oil pressure sensor, WHY THE VACUUM LINE? You don't need a vacuum line to test pressure.

So, there I am good and confused now. Thanks alot.

Lg

Reply to
Lawrence Glickman
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Sure it did...but since Tegger brough up the subject, I thought we could kill two birds with one stone, since I've been watching my fuel pressure fly all over the place...especially going High at times, up to 60 psi, when cruising, and then it will drift back into the 40's psi zone where it should be. Why would it DRIFT like that?

I was just getting on the bus hoping we could both get an answer to our own problems at the same time. Next time I'll wait for the FORD bus. Not meaning to get in the way of Tegger's situation.

Lg

Reply to
Lawrence Glickman

Ok, I see. My bad. Looking back through the thread I found this:

"I monitory my fuel pressure through an OBD II port on my 2003 Vulcan V6. Believe me, it is all over the place, from 35 low to 60 psi high. All over the place. You can see the numbers if you want, as I can post them."

After reviewing the appropriate Ford repair manuals I understand that you do indeed have a Returnless fuel system. No Vulcan listed in my manual, but I assume it has the same system as other Ford models) There is no fuel pressure regulator on the fuel rail, as BOB said. Why is there a vacuum line attached to the pressure sensor? I'll get back to you on that one. It's

3:30 AM here and Ill have to sleep some before I can dig through the Ford manuals for more information on that one. BTW, the pressure variations are normal on that system.

Later,

Reply to
Kevin

Hee hee!

Figures someone would come up with that. Ain't IMDB great?

Toyota MDT > Comboverfish wrote:

Reply to
Comboverfish

That's the way to do it.

You were checking between 5v reference and ground. You need to check between signal return and ground.

Resistance checks are many times useless in determining a component's worthiness.

It's possible that you had it set to 'Autorange' and it was crossing over at some point into the next range. (i.e. if 0-3999 ohms and

0-39999 ohms were two consecutive ranges on your meter, you would see a glitch when you reach 4000 ohms)

Still, look at voltage. Look for around .5 volt across the two wires with engine fully warmed up.

That method is particularly good for looking at the spray patterns, but you must realize that there is nothing securing the injectors to the rail when you remove the components from the cylinder head. Atleast I son't think that Acura employs injector retainer clips. If they do have retainers then go ahead, thinking safety and caution first. I think 10 seconds would be more than enough from a volume standpoint. Ofcourse the longer you go, the more accurately you can control testing inaccuracies. Testing length/errors in timing the tests should be as high a number as practical.

Toyota MDT in MO

Reply to
Comboverfish

"Comboverfish" wrote in news: snipped-for-privacy@j73g2000cwa.googlegroups.com:

I also backprobed the return (-) wire to ground. I got something like .25 volt, and no change with throttle position.

Probing between + and - gets me the expected 5V, but no change with throttle position.

OK...Didn't know that...

It's an autoranging meter (Iequus 3320). Doesn't seem to be any way of disabling that.

The factory manual does not ask me to check for voltage. It gives test procedures and specs for resistance only. I'll check voltage tonight, provided I'm doing it right, which I'm not sure of yet.

So you're not concerned about burning out the injector coils or damaging them in some way? Remember, by grounding them this way I am taking the resistor out of the loop.

Reply to
TeGGeR®

"Comboverfish" wrote in news: snipped-for-privacy@j73g2000cwa.googlegroups.com:

Believe me, the last thing I want is fuel spraying everywhere.

I was going to zip-tie or wire them in place in the fuel rail. My injectors are only held in place by the bolts at either end of the fuel rail, which clamps them between the rail and the manifold runners.

I was also going to use highball glasses to catch the fuel, figuring a tall narrow glass would have less chance of spraying back in my face. I'd build a carrier for the glasses so they wouldn't tip over.

Reply to
TeGGeR®

=3D=3D=3D=3D=3D HAVE IT BRONZED.:--)

mho v=83e

Reply to
fiveiron

The Kevin entity posted thusly:

Hmm... I was told by someone that OBD II is for diagnostics only, which I took to mean 'for static trouble codes'. This seems to say that it can be used for dynamic monitoring of some systems.

I'm interested in finding out more. Is there a good place to get an overview of such things as protocols, etc.?

Reply to
Oleg Lego

Forget the vacuum line- test the fuel pressure directly. I'll bet you anything there's a fuel pressure test port on the fuel rail.

Reply to
Steve

If you have three wires going into the TPS, 1) is 5 volts, 2) is variable voltage return to the ECM, and 3) is ground, typically in that order on the connector.

Most modern DVOMs are autoranging by default. There is often an "Auto" button that you can hold down for some time and the meter will change to manual mode. If there is the word "Auto" or "Autorange" somewhere on the LCD display, then you should be able to toggle it off. Then you set the range to include the highest possible expected value. If you are reading battery voltage then you would set your range to the closetst limit above ~ 15 volts. On a meter that uses 4^10 range divisions, this would be the 0-40 volt range.

The old Honda manuals did not show expected voltages for most of their component tests, just resistance. Pretty worthless, IMO.

Good point. Just keep them attached to the original wiring harnass (incorporating the resistor block on the B+ sides of the injectors) then backprobe the ground control wires in each injector individually. I don't think 10 seconds on-time is going to cause damage to the injectors as long as there is fuel in them. If it makes you feel better, do a 5 second test, but precision becomes more a factor in sample accuracy.

Toyota MDT in MO

Reply to
Comboverfish

This I "could" be wrong about..... but somewhere I read that it was just a safety precaution in case the sensor developed a leak. It would allow the engine to burn the leaking fuel rather than have it dripping on top of the engine. I couldn't find an explanation for it in the service manual though. Maybe Neil or someone else can confirm whether or not this is the reason for a vac. hose...... Bob

Reply to
Bob

There is a test port on each of the 2 fuel rails, but they are plugged with Hex bolts. Both of them. No schrader valves. Bugger that, I haven't the $ to buy a fuel pressure gauge at this time anyhow.

Lg

Reply to
Lawrence Glickman

Much more than just codes! These guys have just about all the information you could want about OBD II.

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Kevin Mouton Automotive Technology Instructor "If women don't find you handsome, they should at least find you handy" Red Green

Reply to
Kevin

The Kevin entity posted thusly:

Thanks a bunch!

Larry

-- Keep your stick on the ice! Red Green

Reply to
Oleg Lego

"TeGGeR®" wrote in news:Xns97B85F9C592ACtegger@207.14.113.17:

Tegger,

Your idea sounds something similar to the equipment I use at college.

It's for diagnosing injector problems and delivery rates and then for giving them an ultra sonic clean.

Have a look on the manufacturers web site, there's lots of useful info there anyway.

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In my experience, injectors seldom need replacing though?

Hope this helps in some way...

Reply to
Ric

"Ric@rdo" wrote in news:Xns97B9E1EF06FBDRicrdo2000freeservec@62.253.170.163:

Can your system diagnose injector coils that are weak? I've been thinking (thinking can be dangerous, I know) about this, and it seems to me that my proposal wouldn't necessarily be able to sense problems that result in injectors that open and close improperly due to a weak coil.

I considered this: Idle injector duration, approx 2ms. Duration under load approx 4ms (just for the sake of argument). At 3,000 rpm (to pick a number), you've got 1,500 injector pulses per minute, or 25 per second. That's 25 openings and 25 closings per second. If the coil is weak and opening is delayed, I would not see that with a single opening and closing during my test. I'd have to simulate actual operation by pulsing the injectors the way they are in service.

I then considered: In order to pulse the injectors, I'd need to rig a breadboard with circuitry and an oscillator that would pulse the injectors for 4ms 25 times per second for as long as it took to fill a CALIBRATED LAB BEAKER (not a Dollar General highball glass) with fuel to the point that differences would be apparent. This breadboard would be necessary to ensure I was cycling the injectors precisely equally.

Finally I decided: Even with the above, I could not diagnose a *sticking* injector, where the pulse and volume might be correct, but the *timing* might be off.

I think I need a professional injector testing place.

And there we have one! The closest ones to me are...British Columbia, 1,200 miles away, or Columbus, Kansas, 700 miles. I think I'll need to find something more local. Thanks for the link though.

I kinda need to find somebody with whom I can schedule the service, and get my injectors back same day, or next day.

It's not usual, no, unless they're electrically bad. This according to my mechanic. However, I also have almost 267,000 miles on my car, so all bets are off as far as that goes. Very few techs have much experience with cars with that kind of mileage.

It all does. Thanks. Comboverfish especially has been a great help.

Reply to
TeGGeR®

"Comboverfish" wrote in news: snipped-for-privacy@e56g2000cwe.googlegroups.com:

I checked the TPS with voltage. It's fine. 0.3V at closed throttle, 4.4 at WOT. Smooth as a baby's bottom through the whole range of travel.

Also checked the intake air temp sensor for resistance. It reports exactly what the manual says it should, just like the coolant temp sensor. I was unable to backprobe either sensor (TW or TA) on account of the sensor design, but I did later discover the round connector near the injector resistor at the firewall, which *can* be backprobed. I'll check for voltage tomorrow, but frankly I'm not convinced I'll find anything wrong. So far, NOTHING has checked out bad.

Fuel pressure was checked yesterday by my local Acura dealer. It's absolutely perfect: 40psi. Acceptable range is 37-44 psi. They also confirmed my test that the regulator is not leaking.

So far, the ONLY thing that has resulted in ANY change in the vibration has been the first Motorvac test, which made it worse. I suspect there's an injector mismatch that was buffered by deposits on the other injectors or valves. Now that they're gone, the mismatch is plain.

The problem HAS to be the injectors.

Reply to
TeGGeR®

We use a digital Storage Oscilloscope with an inductive amp probe to monitor current ramping on injectors in order to determine propper electrical and mechanical funtion of the injectors. The pattern of current changes makes it easy to identify injectors that have electrical or mechanical problems. This still dosen't really indicate flow rate problems due to dirty nozzles though.

Reply to
Kevin

How about a couple of cheap suggestions?

Do a quick test of the injectors - do you see one or two that are obviously bad (low flow, lousy pattern?)

Head to the junkyard and procure a couple of used injectors and swap 'em around - see if it changes the symptoms.

Fwiw, the wife's Beretta has 235,000km on it on the original injectors - but they're starting to clack like a diesel now and the idle isn't what it used to be.

I just wonder if you're overthinking the diagnosis of a bad injector - it might be blatantly obvious that one injector has packed it in by the spray.

Ray

Reply to
ray

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