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Faulty Fuel Injector causing mis at startup?


First pic is from truck as I bought it. Had been sitting who knows how long. Pic was April 2021.
Second two pics, the numbered ones, are from a few months later after driving a bunch. Summer 2021. Numbered them in case I could diagnose stuff in future, like now for instance!
So I’ve replaced them all twice.

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Hard to tell from the pic. But it looks like #4 is doesnt have a reddish tint (comes from certain additives stations put in the fuel)

I would say you got a #4 injector not functioning properly.
 
Hard to tell from the pic. But it looks like #4 is doesnt have a reddish tint (comes from certain additives stations put in the fuel)

I would say you got a #4 injector not functioning properly.
Hmmm. Well if it was as easy to change a single injector as it is to change a single spark plug, I’d just buy one nice injector and go one by one and see what solved the problem!
I think what I’m hoping is to find something wrong with some injector gaskets/filters, and be able to get all 6 working like new again.
I see that there are plenty of cheap sets in the $50-75 range, but I’m assuming that once I ran the truck I would find that one or more of them just didn’t work. I’m sure quality control is very low. But I could spring for a nice set, it’s just pretty expensive.
Maybe I’ll try to DIY test my old ones while out of the truck, once I have new gaskets and filters in them.
 
I put cheapos in mine and theyve been fine lol.

Doing injectors is a bit more involved then a plug. Remove the upper intake, pull the bolts off the fuel rail, unhook lines, then remove the rail.
 
No, the injector will leak down all the time in my experience. Its just that on a hot restart that cylinder will be flooded, but on a cold start the gas will have had time to run down past the rings into the oil so that cylinder won't be flooded (plus on cold start more gas is often good). But if you have a newish fuel pump and still need to cycle the key a couple times to have fuel pressure at startup, that suggests that the pressure is leaking out somewhere else, and an injector is a good guess. There are a couple other options, like the schrader valve you mentioned and the pressure regulator, but they are less likely than the injector in my experience.

fwiw, I think the plugs look fine.
 
What are those rebuild kits you mention, 10 bucks on ebay, can you get those at a parts store?
 

But I actually just canceled that order and ordered this remanufactured set instead…


Trying to save time here this week, and I figure with 100% rating, tons of good reviews of reman injectors, a clear return policy and almost 20k sales overall, it can’t be too disastrous haha. I just don’t want to do the work on mine and discover they still are faulty and/or have to set up for spray testing. Will still keep my old ones just in case I have to fall back to to rebuilding those.

Ive checked my spark plugs more recently too, and never saw any issues with them. I wonder how it’s possible that fuel can be leaking into a cylinder and cause this startup issue but not leave any rich looking results on the spark plug. Or maybe it is and I’m just not looking for the right visual indication.

In any case I am taking off the upper intake today and hopefully fuel rail. Will have to disassemble a bunch of small stuff above it all too, so am considering popping open the valve covers to finally take a look at the insides and possibly clean up some gunk if it’s built up in there. I think I can do this without changing the oil, but am also probably going to change the oil anyways since it was mentioned here that leaking injector can get fuel down into oil? Is that right?
 
When you pull the fuel rail dont forget about the hidden bolt behind the drivers side valve cover.

I did, thought the injectors were stuck and took a prybar to the fuel rail.

I ended up replacing the rail cause i bent the piss out of it. Luckly i had a spare but 2.9 fuel rails arnt exactly easy to come by
 
When you pull the fuel rail dont forget about the hidden bolt behind the drivers side valve cover.

I did, thought the injectors were stuck and took a prybar to the fuel rail.

I ended up replacing the rail cause i bent the piss out of it. Luckly i had a spare but 2.9 fuel rails arnt exactly easy to come by

Thank you! Yeah i have been looking around for fuel rails on the inter webs, just assuming i'll discover mine are shabby, but there isn't anything for sale anywhere. I'll be sure to be careful with the bolts/removal...
 
Thank you! Yeah i have been looking around for fuel rails on the inter webs, just assuming i'll discover mine are shabby, but there isn't anything for sale anywhere. I'll be sure to be careful with the bolts/removal...
The biggest failure point on 2.9 fuel rails are rust inside the rail, plugging everything up, or tiny pinholes making leaks (thanks ethanol)
 
Hard to tell from the pic. But it looks like #4 is doesnt have a reddish tint (comes from certain additives stations put in the fuel)

I would say you got a #4 injector not functioning properly.

Maybe it’s luck, or maybe you have an eagle eye!

When I got the upper intake out, I started looking closer at the fuel rail and reached out to touch injector #4 and it spun freely. Like with a light touch using finger tips I could spin that injector a bunch. That’s with the fuel rail still fully mounted and tightened down. Once i got the electrical connector off of that one, it spun even easier.

Any theories as to what major air leak into cylinder #4 would do to its performance? Seems like it would be a pretty big deal. I’m assuming it’s worn gaskets, and I’m assuming there’s a good chance some of the others are near shot as well.

What’s weird to me is that it never amount to a visible fuel leak on #4. Or maybe it was so small I never caught it.

I didn’t yet mess with the others, I just got right to work…. I have all the bolts out, including the hidden one, and have 5 of 6 electrical clips off. The last clip, I think it’s cyl #6, is tough to unclip since access of the side latch is near impossible. So I’m hoping to just lift the whole fuel rail up and disconnect that clip a little easier that way.

Iv got to study up on what exactly to expect when pulling on the rail and what is supposed to give and where.

Looking forward to having the rail out and cleaning it. Hopefully it’s useable still.

I’m also not sure how to detach the main fuel input line from the rail. Circled in red below. The regulator is out, but that line has some sort of grip on the rail input that is very flexible inside and wants to remain connected and springs back no matter how much you tug away. It’s going a good job holding on and feeding the truck fuel! But it is confusing to work with.

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You need something like this: Fuel And Transmission Line Disconnect Tool Set, 7 Piece (harborfreight.com) .
It goes around the metal tube on the fuel rail and pushes back into the connector. this pushes the spring inside the connector outwards so the connector can slide off. I have this exact set and have had to do a little file work on it to get it to go in easier. There is probably a better set that fits better.
 

But I actually just canceled that order and ordered this remanufactured set instead…


Trying to save time here this week, and I figure with 100% rating, tons of good reviews of reman injectors, a clear return policy and almost 20k sales overall, it can’t be too disastrous haha. I just don’t want to do the work on mine and discover they still are faulty and/or have to set up for spray testing. Will still keep my old ones just in case I have to fall back to to rebuilding those.

Ive checked my spark plugs more recently too, and never saw any issues with them. I wonder how it’s possible that fuel can be leaking into a cylinder and cause this startup issue but not leave any rich looking results on the spark plug. Or maybe it is and I’m just not looking for the right visual indication.

In any case I am taking off the upper intake today and hopefully fuel rail. Will have to disassemble a bunch of small stuff above it all too, so am considering popping open the valve covers to finally take a look at the insides and possibly clean up some gunk if it’s built up in there. I think I can do this without changing the oil, but am also probably going to change the oil anyways since it was mentioned here that leaking injector can get fuel down into oil? Is that right?


I bought a set of these after cheap replacements wreaked havoc on my 2.9. Many new injectors spray from multiple holes, which is a very different spray pattern and volume (like a spray bottle or glass cleaner) from original injectors (who have a single pintle, and spray pattern more like that of a squirt gun.
 
I bought a set of these after cheap replacements wreaked havoc on my 2.9. Many new injectors spray from multiple holes, which is a very different spray pattern and volume (like a spray bottle or glass cleaner) from original injectors (who have a single pintle, and spray pattern more like that of a squirt gun.

You got the same set from the same seller? (After you bought a bad set.) And these have worked ok so far?
When I received them I’m planning to compare the design to my old ones just to make sure they are in fact going to operate like OEM. Would be funny if my old ones weren’t even OEM. Who knows what’s in there. But I’m guessing they are, and that the severely failing orings is due to sitting for like 10 years and drying out and cracking.
 
Sorry, the ad image and language looked similar. I actually purchased from this seller:


and they worked beautifully, up until unforeseen issues with bad/rusty fuel damaged them. The seller did honor the warranty and replaced the injectors, but I did have to send back the damaged injectors at my own cost. Either way, very happy with both the seller and the product.
 

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