Sticking fuel injector(s)

[JD's Toy]

I suspect I have a sticking fuel injector, hoping somebody can confirm. Also, with no way to know which one is sticky should I just buy a set of 8?

Some facts.
First off - I've had a really bad idle which up to this time I've said is likely due to a faulty IAC valve. Idle will drop to about 500 rpm at a light and it'll run really rough for a few mins. If the light is long enough the idle will pop back and forth between a nice smooth idle at 700 rpms or so and a rough idle at 500 rpms that nearly stalls me.

Had the flu last week. Wagon sat exactly 7 days. Started it this morning and it would not remain running. It'd rev up to 2000 rpms and then fall straight to 0 rpms. Again I'd think this could be the IAC sticking closed. After 6 or 7 starts it started to "catch" and eventually i got into work. Now everytime I'm at a red light it idles really rough, like it's not firing on all cylinders.

On the highway on the drive in, it definately wasn't firing on all cylinders. I'd have to depress the pedal to get the sucker into 3rd gear to be able to maintain speed. Now if I floorded it it'd immediately downshift but I'd have 0 power for a good amount of time. Eventually it's like somebody flicked a switch (fuel injector??) and it'd be like a mule kicked the back of the car and it'd take off. Finally, I've had a ghost code for a little while now on the wagon. Engine running lean in a continuous memory code. Never pick it up on the KOER test, but it's always there on the continuous memory. My thought is I probably have a bad injector or two that is causing a lean condition during operation that I haven't really noticed until now.

Also, it SEEMED like the situation improved as i drove it into work and got some miles on it. That could be my imagination though...

Fuel injectors are used items that I purchased from somebody on here I believe. I've already ran a bunch of injector cleaner though them just knowing they were used items. Do I keep down this path or just replace them? Do people agree that this is a fuel issue? Is there a fuel injector cleaner that I can buy that'll do a good job of actually cleaning them?

Thanks,
JD

[JD's Toy]

if it helps at all, my code in continuous memory is 41 - right side lean. Right side = passenger side?

[85crownHPP]

Pull each plug and check them out - usually a bad injector will show on the plug. Try tapping on the IAC with a small hammer and see if that helps the starting/idling issue.

[mrltd]

yes, right is passenger side.

I'd check the fuel filter and the big connectors on the side of the intake. It could also be a bad O2 sensor. The kick in the ass is the car switching from closed to open loop and running off the set tables, ignoring a few sensors

[Pirate]

I suspect I have a sticking fuel injector, hoping somebody can confirm. Also, with no way to know which one is sticky should I just buy a set of 8?

Some facts.
First off - I've had a really bad idle which up to this time I've said is likely due to a faulty IAC valve. Idle will drop to about 500 rpm at a light and it'll run really rough for a few mins. If the light is long enough the idle will pop back and forth between a nice smooth idle at 700 rpms or so and a rough idle at 500 rpms that nearly stalls me.

Had the flu last week. Wagon sat exactly 7 days. Started it this morning and it would not remain running. It'd rev up to 2000 rpms and then fall straight to 0 rpms. Again I'd think this could be the IAC sticking closed. After 6 or 7 starts it started to "catch" and eventually i got into work. Now everytime I'm at a red light it idles really rough, like it's not firing on all cylinders.

On the highway on the drive in, it definately wasn't firing on all cylinders. I'd have to depress the pedal to get the sucker into 3rd gear to be able to maintain speed. Now if I floorded it it'd immediately downshift but I'd have 0 power for a good amount of time. Eventually it's like somebody flicked a switch (fuel injector??) and it'd be like a mule kicked the back of the car and it'd take off. Finally, I've had a ghost code for a little while now on the wagon. Engine running lean in a continuous memory code. Never pick it up on the KOER test, but it's always there on the continuous memory. My thought is I probably have a bad injector or two that is causing a lean condition during operation that I haven't really noticed until now.

Also, it SEEMED like the situation improved as i drove it into work and got some miles on it. That could be my imagination though...

Fuel injectors are used items that I purchased from somebody on here I believe. I've already ran a bunch of injector cleaner though them just knowing they were used items. Do I keep down this path or just replace them? Do people agree that this is a fuel issue? Is there a fuel injector cleaner that I can buy that'll do a good job of actually cleaning them?

Thanks,
JD

If you decide to clean the injectors later....the 'wonder' chemicals you buy in a bottle don't work too well in cleaning the injectors out. Methinks you should have them professionally cleaned, or just buy a new set like Tom did. However, if you purchased a set of Exploder injectors...I'd have them cleaned instead.

[gadget73]

Could also be a ripped O ring on the injector base. If its sucking air around the injector, it will run funny and lean. Some penetrating lube sprayed around the base of the injectors will tell you if thats the problem.

[JD's Toy]

little bit of an update for y'all. I have an adjustable fuel pressure regulator on the car and prior to this it was set at like 65 psi. I fiddled with it a little bit and if i decreased pressure the car would just die.

i cranked it all the way up to max psi (about 85 psi at the rail now) and the stumbling at idle has greatly decreased. the "switching" when floored is gone. It's always "on" now.

Also, my elusive "lean" code is gone, no rich codes.

so definately seems like a fuel related problem. and since i have real high pressure at the rail i'm thinking it's gotta be the injectors themselves. gummed up and they have too high of a pressure drop across them now.

oh, also i put my ear to each of the injectors and they are all clicking like they should be, so they are attempting to get the fuel in...

I'll keep my eyes peeled for a new set of injectors at a reasonable price for it. lemme know if anybody has a set lying around! also please let me know if you think i've missed something in my troubleshooting!

[Pirate]

little bit of an update for y'all. I have an adjustable fuel pressure regulator on the car and prior to this it was set at like 65 psi. I fiddled with it a little bit and if i decreased pressure the car would just die.

i cranked it all the way up to max psi (about 85 psi at the rail now) and the stumbling at idle has greatly decreased. the "switching" when floored is gone. It's always "on" now.

Also, my elusive "lean" code is gone, no rich codes.

so definately seems like a fuel related problem. and since i have real high pressure at the rail i'm thinking it's gotta be the injectors themselves. gummed up and they have too high of a pressure drop across them now.

oh, also i put my ear to each of the injectors and they are all clicking like they should be, so they are attempting to get the fuel in...

I'll keep my eyes peeled for a new set of injectors at a reasonable price for it. lemme know if anybody has a set lying around! also please let me know if you think i've missed something in my troubleshooting!

When you put the HO motor in this car, did you also replace the fuel pump to an H.O. unit?

[JD's Toy]

nope. did not replace the fuel pump... if i had the problem more at wide open throttle i'd suspect the fuel pump, but the car seems to run better at wide open throttle than at any part throttle...

since it runs good at wide open and i'd expect i'm gettting proper fuel flow.

[91waggin]

maybe have the injectors professionally sonic cleaned? That did wonders for my gas mileage after I had it done. I assume that the computer was able to regulate the fuel flow more precisely and not squirt more than was needed.

[JD's Toy]

ordered up a set of explorer injectors that have been remanufactured today... found them on ebay for a song. i'll let everyone know how it goes!

[gadget73]

um, you know the stock fuel pressure is like 42 psi with no vacuum right? At 85 psi, you're doubling the flow per injector pulse. Either you have majorly screwed injectors, or something else is very wrong here.

The stock fuel pump can keep up with an HO, but only if its in good shape. If you have a clogged filter or something, it will run all stupid. Usually idle is fine, it requires very little fuel to idle. When you don't have enough fuel flow, WOT will fall on it's face badly. Cruise is usually more or less OK, it gets worse with more load since the fuel demand goes up.

[marquisman]

almost sounds like my wagon lol.

[mrltd]

crimped plastic fuel line? the return line specifically....

[import convert]

does your pump have a whine to it at all? FPR gone bad? or have i forgot if we have one shince ive gone carb? sounds like a vacume leak to me but with the higher preassure it makes up for the extra air