Checking fuel pump or injectors?

2tone

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So I seem to have a problem with my injectors or high pressure fuel pump but my usual shop says they don’t have the knowledge or experience with the new gen to know what to look for and they don’t want to charge me to start replacing things without being sure it’ll fix it. Are the injectors that hard to visually check? Is this something that needs to be done by Honda themselves?

Updates on page 2

Update: finally got the car fixed, it turns out the shop I had my spark plugs replaced at decided for themselves that they should go a step colder for my aftermarket car(even though I asked for oem plugs) but apparently they put plugs with a completely wrong gap size causing my cat to fail and all the problems. Glad to have my car running well again after almost three months of running with incorrect plugs, I hope this didn’t cause any damage to the engine. The shop is reimbursing me for what Honda charged to change the plugs and running compression test etc to make sure there was no damage


Update: spark plug replacement didn’t solve the issue, I’m guessing the incorrect plugs caused the issue in the first place especially since the problem started shortly after having them installed.
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Triple_peaz

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I would do as much research I can first. Second option would be Honda. Are you using after market parts?
 

charleswrivers

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I think thing they're not much different than any other injector with regard to checking the resistance of it's coil. It does run at a high pressure and may inject fuel over a different amount of time and even have 2 injection events vs one but it's still fundamentally a similar device. I'm not sure what the spec is. Perhaps someone who's pulled one apart might know.

Honda Civic 10th gen Checking fuel pump or injectors? aac9fea116417c5af46ec7b75fe90b38

You still have the regular old conventional fuel pump/filter set back at the tank.
Honda Civic 10th gen Checking fuel pump or injectors? a4c47fce73738dbe6e859eb1f196512a

So far as the HP fuel pump... I don't know a great deal about it. I assume is driven off the cam. Either way, are you able to see pressure via your OBD2? You say there's a problem but I'm not sure what issue you're having. A lot of car makers are using DI and have been for several years, so your usual shop is a bit behind the times.

I did go out and look at my engine for a moment. I figured they were in the back... and yeah, sure enough... they're back there. I attached a link for a video. Skip to around 5:30 and it'll show their location. It's a bit of a PITA to bend back in that spot... but they're back there. There's so much void between the engine and the firewall, I almost wonder if it's be easier to put the car on a lift and access them from underneath. If you can access them, you need not pull them. Just pull the clips and measure their resistance if someone can post the nominal spec. Otherwise you can always measure them all and compare. If an injector has failed, it is very unlikely more than one failed... that that won't reliably tell you whether or not an injector has failed mechanically. You'd have to look at your fuel trims for that. OBD2 should give you that again.

Many Z cars with many failed injectors in the post-ethanol age that killed the original design ones. Good luck. Make sure you're going after the right thing though and not chasing your tail. Again, the video is well worth a watch... it explains the layout very well. I spend a good chunk of change for a FSM if one were available. My Z32s one is available as a free app.

 
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I would do as much research I can first. Second option would be Honda. Are you using after market parts?
Stage 1 vit tune, catted downpipe, and an Intercooler
 
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I think thing they're not much different than any other injector with regard to checking the resistance of it's coil. It does run at a high pressure and may inject fuel over a different amount of time and even have 2 injection events vs one but it's still fundamentally a similar device. I'm not sure what the spec is. Perhaps someone who's pulled one apart might know.

aac9fea116417c5af46ec7b75fe90b38.gif

You still have the regular old conventional fuel pump/filter set back at the tank.
a4c47fce73738dbe6e859eb1f196512a.gif

So far as the HP fuel pump... I don't know a great deal about it. I assume is driven off the cam. Either way, are you able to see pressure via your OBD2? You say there's a problem but I'm not sure what issue you're having. A lot of car makers are using DI and have been for several years, so your usual shop is a bit behind the times.

I did go out and look at my engine for a moment. I figured they were in the back... and yeah, sure enough... they're back there. I attached a link for a video. Skip to around 5:30 and it'll show their location. It's a bit of a PITA to bend back in that spot... but they're back there. There's so much void between the engine and the firewall, I almost wonder if it's be easier to put the car on a lift and access them from underneath. If you can access them, you need not pull them. Just pull the clips and measure their resistance if someone can post the nominal spec. Otherwise you can always measure them all and compare. If an injector has failed, it is very unlikely more than one failed... that that won't reliably tell you whether or not an injector has failed mechanically. You'd have to look at your fuel trims for that. OBD2 should give you that again.

Many Z cars with many failed injectors in the post-ethanol age that killed the original design ones. Good luck. Make sure you're going after the right thing though and not chasing your tail. Again, the video is well worth a watch... it explains the layout very well. I spend a good chunk of change for a FSM if one were available. My Z32s one is available as a free app.

Thanks for all the info and link! Sorry, to give more background, my car is misfiring only under full boost(~18+psi) and running lean. Drob and javi have looked at my data log, and drob said “I’m inclined to say you have an injector problem”. I would imagine drob is right but the shop said based on the tests they ran on my car they can’t be sure without replacing them and they don’t want to charge me for it without being sure it’s a fix. I’m not 100% on what tests were ran since I was at work all day and picked my car up after the shop was already closed. I do know they include compression tests and swapping spark plugs, and fuel pressure. They said that there best guess is either the hp fuel pump or injectors so I imagine they ran any available test they could related to them. It seems like they couldn’t narrow it down to one or the other and didn’t want to just pick one and charge me for it to find out it was the other.
 


charleswrivers

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Well, you should be able to check pressure from you're... well call it the LPFP, that's tank based. It feeds the HPFP. From there the HPFP will boost the 10s of lbs of pressure but a lot of volume (it's a little centrifugal pump) to it's 1000s of lbs of pressure. This pressure isn't static I don't think, it can vary. I'm not really sure what drives it. I assume it's driven off the cam, which would mean it's pressure would vary with engine speed and duration of injection, with pressure building when it has no place to go (injectors shut. If makes sense to me that it's got to be a positive displacement pump (not that it matters too much) other than if there's any issues with whatever passes for it's plunger, as it tries to push, there'll be back flow back towards the LPFP side and pressure won't ever get as high as it should be. Then, obviously the injectors themselves. I'd of thought you'd throw a code if your fuel trims were out of wack low. Again, you can check it's coil used to turn them on... but if they failed mechanically, this won't work. I've dies the 'listen for tapping' tests before on my Z's, but that never worked for me that well. Those cars have notoriously loud lifters half the time and can mask other noises.

I'd caution you against pushing the car too hard. Running lean can damage an engine in a hurry. If you are running lean though, I would pull all my plugs and read them. If one one is lean (I'll post a chart at the end of this) then only that cylinder is lean and likely your injector on that cylinder is electrically failed or mechanically stuck shut. When rejetting carburators, I'd got WOT for a bit, then kill the engine and read them. Hot and white is lean. Mind you you'd need to cause the lean condition to accomplish this... kind of undesirable, but a method none the less. I would also make a caveat, DI engine are a lean burning engine by design in some cases and will sometimes do intentional stratified mixes. It may be, depending on how the engine is being asked to run at the time, all the plugs could look lean.

Honda Civic 10th gen Checking fuel pump or injectors? spark-plug-running-600


All and all, no car should be outside it's powertrain warranty yet, with the oldest one being a 2016. I'd revert to stock and take it to a dealer.
 
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Well, you should be able to check pressure from you're... well call it the LPFP, that's tank based. It feeds the HPFP. From there the HPFP will boost the 10s of lbs of pressure but a lot of volume (it's a little centrifugal pump) to it's 1000s of lbs of pressure. This pressure isn't static I don't think, it can vary. I'm not really sure what drives it. I assume it's driven off the cam, which would mean it's pressure would vary with engine speed and duration of injection, with pressure building when it has no place to go (injectors shut. If makes sense to me that it's got to be a positive displacement pump (not that it matters too much) other than if there's any issues with whatever passes for it's plunger, as it tries to push, there'll be back flow back towards the LPFP side and pressure won't ever get as high as it should be. Then, obviously the injectors themselves. I'd of thought you'd throw a code if your fuel trims were out of wack low. Again, you can check it's coil used to turn them on... but if they failed mechanically, this won't work. I've dies the 'listen for tapping' tests before on my Z's, but that never worked for me that well. Those cars have notoriously loud lifters half the time and can mask other noises.

I'd caution you against pushing the car too hard. Running lean can damage an engine in a hurry. If you are running lean though, I would pull all my plugs and read them. If one one is lean (I'll post a chart at the end of this) then only that cylinder is lean and likely your injector on that cylinder is electrically failed or mechanically stuck shut. When rejetting carburators, I'd got WOT for a bit, then kill the engine and read them. Hot and white is lean. Mind you you'd need to cause the lean condition to accomplish this... kind of undesirable, but a method none the less. I would also make a caveat, DI engine are a lean burning engine by design in some cases and will sometimes do intentional stratified mixes. It may be, depending on how the engine is being asked to run at the time, all the plugs could look lean.

spark-plug-running-600.jpg


All and all, no car should be outside it's powertrain warranty yet, with the oldest one being a 2016. I'd revert to stock and take it to a dealer.
Yea we read the plugs at the shop and they showed being lean. Going back to stock would cost me a bit of money or more time then I’d like to have my cars problems un resolved. I’m thinking about just taking it to Honda tomorrow since it’s my only day off and just paying for whatever may be the problem. Going back to stock would require me paying a shop or waiting until me and my uncle who lives 2hours away had I know some service guys there who are into modding 10th gens so maybe they’ll help out a bit. And I think the problem the shop was having was that the car is running completely fine until high boost, so it made it hard to pinpoint I guess?
 

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Yea we read the plugs at the shop and they showed being lean. Going back to stock would cost me a bit of money or more time then I’d like to have my cars problems un resolved. I’m thinking about just taking it to Honda tomorrow since it’s my only day off and just paying for whatever may be the problem. Going back to stock would require me paying a shop or waiting until me and my uncle who lives 2hours away had I know some service guys there who are into modding 10th gens so maybe they’ll help out a bit. And I think the problem the shop was having was that the car is running completely fine until high boost, so it made it hard to pinpoint I guess?
Sounds like a plan. Good luck! Regardless of mods, IMO, things like LPFP... injectors... HPFP... fuel pressure regulators, etc would be things that would not be denied based on mods. The pumps will work happily, regardless of system load. The injectors would just get longer pulses and operate at a higher duty cycle. I don't feel like you can attribute your mods to issues with the car's fuel system. The only thing that might give them grounds would be if you're using E85. I think the manual specifies E15 it less (my memory might be off). Since you're not doing the flexfuel thing, I'd say you're good to go.
 
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Sounds like a plan. Good luck! Regardless of mods, IMO, things like LPFP... injectors... HPFP... fuel pressure regulators, etc would be things that would not be denied based on mods. The pumps will work happily, regardless of system load. The injectors would just get longer pulses and operate at a higher duty cycle. I don't feel like you can attribute your mods to issues with the car's fuel system. The only thing that might give them grounds would be if you're using E85. I think the manual specifies E15 it less (my memory might be off). Since you're not doing the flexfuel thing, I'd say you're good to go.
Awesome! Thanks for the advice.
 


SaintClarence27

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Well, you should be able to check pressure from you're... well call it the LPFP, that's tank based. It feeds the HPFP. From there the HPFP will boost the 10s of lbs of pressure but a lot of volume (it's a little centrifugal pump) to it's 1000s of lbs of pressure. This pressure isn't static I don't think, it can vary. I'm not really sure what drives it. I assume it's driven off the cam, which would mean it's pressure would vary with engine speed and duration of injection, with pressure building when it has no place to go (injectors shut. If makes sense to me that it's got to be a positive displacement pump (not that it matters too much) other than if there's any issues with whatever passes for it's plunger, as it tries to push, there'll be back flow back towards the LPFP side and pressure won't ever get as high as it should be. Then, obviously the injectors themselves. I'd of thought you'd throw a code if your fuel trims were out of wack low. Again, you can check it's coil used to turn them on... but if they failed mechanically, this won't work. I've dies the 'listen for tapping' tests before on my Z's, but that never worked for me that well. Those cars have notoriously loud lifters half the time and can mask other noises.

I'd caution you against pushing the car too hard. Running lean can damage an engine in a hurry. If you are running lean though, I would pull all my plugs and read them. If one one is lean (I'll post a chart at the end of this) then only that cylinder is lean and likely your injector on that cylinder is electrically failed or mechanically stuck shut. When rejetting carburators, I'd got WOT for a bit, then kill the engine and read them. Hot and white is lean. Mind you you'd need to cause the lean condition to accomplish this... kind of undesirable, but a method none the less. I would also make a caveat, DI engine are a lean burning engine by design in some cases and will sometimes do intentional stratified mixes. It may be, depending on how the engine is being asked to run at the time, all the plugs could look lean.

spark-plug-running-600.jpg


All and all, no car should be outside it's powertrain warranty yet, with the oldest one being a 2016. I'd revert to stock and take it to a dealer.
Powertrain isn't unlimited miles, is it?
 

charleswrivers

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Powertrain isn't unlimited miles, is it?
5 years and 60k miles. I suppose there may be some past the 60k miles... but no one past the time. I didn't think so much about mileage as I'm at nearly 1.5 years and only at 11k. Sometimes I forget there are folks that have long commutes. If it wasn't for some intentional long drives to use it vice the larger and more long-trip friendly Odyssey, I'd be well under 10k still.
 
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Any update on this OP? Would like to hear more about this.
I won’t be able to get my car looked at by Honda until Saturday morning sadly, I will update the thread when I get more info
 

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5 years and 60k miles. I suppose there may be some past the 60k miles... but no one past the time. I didn't think so much about mileage as I'm at nearly 1.5 years and only at 11k. Sometimes I forget there are folks that have long commutes. If it wasn't for some intentional long drives to use it vice the larger and more long-trip friendly Odyssey, I'd be well under 10k still.
I guess I'm likely to be in the painful position of using up the miles. 2300k after 1 month.
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