Check my plugs

[djcodeman]

Yea, it was a gradual thing. At first I had the off idle thing every now and again but it has progressed to over half the time. Quite frustrating.

It could be the tune. Not ruling anything out. I can't seem to see anything in the logs and i've had all the smart guys in the forum have a look as well. It's very difficult to see anything that's going wrong. A lot of what i'm doing to rule things out is also so if I go back to the tuner to have a look I don't waste anyone's time to do these things then. I will have some concrete information that will hopefully help them help me.

have the tuner look at it.

Sponsored

 

[Optimum Performance]

What does the tuner say about the data logs? What fuel? Verify fuel quality, close up the gap .002". Valve spring seat pressure, VVCT, timing. Try a hotter plug to see if it clears up at idle.

 

[Angrey]

You have to be careful of spurious and false relationships when diagnosing. Just because something is correlated to the tune, doesn't necessarily mean it's tune. Could be that the tune is struggling to provide adequate spark under those conditions (where it changes). Never assume. Checking the harness is drastic and expensive but there's a lot of OTHER issues that end up not being sensor or mechanical component, but connections and/or harness.

Furthermore, if the issue has "progressed" over time, unless you've changed the tune, that's indicative of it being something physical or component related. Not saying it's not the tune, but if it's grown, that's usually a symptom of something mechanical/wiring. In some cases, the progression is due to running it like that long enough that it effects the physical components (so it could still be the tune, but less likely).

If you've checked the coils, I'm betting it's either harness OR something in your charging system that's not giving it adequate juice under certain conditions, which is causing it to misfire.

 

[Torinate]

What does the tuner say about the data logs? What fuel? Verify fuel quality, close up the gap .002". Valve spring seat pressure, VVCT, timing. Try a hotter plug to see if it clears up at idle.

You have to be careful of spurious and false relationships when diagnosing. Just because something is correlated to the tune, doesn't necessarily mean it's tune. Could be that the tune is struggling to provide adequate spark under those conditions (where it changes). Never assume. Checking the harness is drastic and expensive but there's a lot of OTHER issues that end up not being sensor or mechanical component, but connections and/or harness.

Furthermore, if the issue has "progressed" over time, unless you've changed the tune, that's indicative of it being something physical or component related. Not saying it's not the tune, but if it's grown, that's usually a symptom of something mechanical/wiring. In some cases, the progression is due to running it like that long enough that it effects the physical components (so it could still be the tune, but less likely).

If you've checked the coils, I'm betting it's either harness OR something in your charging system that's not giving it adequate juice under certain conditions, which is causing it to misfire.

I hear you,

Haven't had the tuner review these logs yet. Wanted to make sure I tried all the possible causes I could so they didn't send me away to try them. Compression is spot on. Have not tested valve seat spring pressure. Would a soft spring come up on idle only or cause the tip in hesitation? What's the process of testing that? I imagine disassembly, head removal etc? Fuel is consistently from the same 3 stations - Petro Canada 94 octane. Has always been my "go to place" between 3 different stations and never had an issue.

Have moved coils around without success. Really don't think it's the harness but I did have a close look at all the spots I could see and the connectors for the coils and injectors. Did not remove the wire loom or the factory tape. Would using a dielectric grease on every connector help? Lambda and fuel trims have been consistent with original logs when tune was first done.

Yes... progressed over time. I never looked for any idle misfires until it started popping at idle. The tip in also changed. I remember initially when it would happen every now again - just once and usually the first or second time pulling away from a stop sign on my street I had the delay - then it would be fine after that. Now, it happens 50-60% of the time without any rhyme or reason. Step on the gas and it goes, or step on the gas and it decides to wait a second before going. Someone mentioned possibly transmission as well. This is the beauty of the problem! It could be 1 of 100 different things and in any combination. No CELs though. So I KNOW there's an issue, but the car doesn't...

That's an interesting proposition about the battery / charging system. With that said, I am still on the original battery. It has never shown an issue. It's on a battery tender and stored in a heated garage in the winter. Certainly something to think about. Plugs are new. 6510s as recommended by tuner and gapped at 028. Would a stock heat range plug help the idle, but what would it do under boost / load?

I too wondered about the VCT and possibly an issue at idle or a slow response on tip in. Others have looked at the logs and didn't see anything that stood out. With that said though, the logs are the typical logs that the tuner has you do, so lots of PIDs that could potentially slow down the responses of all of them i'm told.

I appreciate the time and energy to help out!

 

[Angrey]

I hear you,

Haven't had the tuner review these logs yet. Wanted to make sure I tried all the possible causes I could so they didn't send me away to try them. Compression is spot on. Have not tested valve seat spring pressure. Would a soft spring come up on idle only or cause the tip in hesitation? What's the process of testing that? I imagine disassembly, head removal etc? Fuel is consistently from the same 3 stations - Petro Canada 94 octane. Has always been my "go to place" between 3 different stations and never had an issue.

Have moved coils around without success. Really don't think it's the harness but I did have a close look at all the spots I could see and the connectors for the coils and injectors. Did not remove the wire loom or the factory tape. Would using a dielectric grease on every connector help? Lambda and fuel trims have been consistent with original logs when tune was first done.

Yes... progressed over time. I never looked for any idle misfires until it started popping at idle. The tip in also changed. I remember initially when it would happen every now again - just once and usually the first or second time pulling away from a stop sign on my street I had the delay - then it would be fine after that. Now, it happens 50-60% of the time without any rhyme or reason. Step on the gas and it goes, or step on the gas and it decides to wait a second before going. Someone mentioned possibly transmission as well. This is the beauty of the problem! It could be 1 of 100 different things and in any combination. No CELs though. So I KNOW there's an issue, but the car doesn't...

That's an interesting proposition about the battery / charging system. With that said, I am still on the original battery. It has never shown an issue. It's on a battery tender and stored in a heated garage in the winter. Certainly something to think about. Plugs are new. 6510s as recommended by tuner and gapped at 028. Would a stock heat range plug help the idle, but what would it do under boost / load?

I too wondered about the VCT and possibly an issue at idle or a slow response on tip in. Others have looked at the logs and didn't see anything that stood out. With that said though, the logs are the typical logs that the tuner has you do, so lots of PIDs that could potentially slow down the responses of all of them i'm told.

I appreciate the time and energy to help out!

I didn't even consider the VCT and cam timing. Could be if you're only seeing it at idle conditions where the adjustment is full.

Problem with Ford's ridiculous charging system is it may still be within parameters for the alternator/battery but at lower rpm where the alternator tries to conserve effort, current may not be enough to fire properly. Worth looking into. If you're due for a battery change, try swapping that out first and see if the problem persists.

 

[Torinate]

Yea. Not a bad idea really... Thanks!

 

[SheepDog]

I moved the coils around last time as well. It didn’t change anything. I think you’re right. Misfiring enough to register but not a high enough percentage to trip a CEL. The misfires are most prevalent in cylinder 1 but all of them are registering misfires. I put the plugs back in and actually moved all of the coils this time as well. Basically switched them side to side.
I think maybe I’ll do another smoke test but that’s not likely the culprit. I spent an hour checking every connection and wire that I could get to on the wiring harness hoping to maybe find a chafed wire but nothing. I didn’t remove any of the factory tape to look under it though. Grounds are tight. I’m missing something.

Have you put a bore scope down into the cylinders through the spark plug hole to check for carbon deposits on the pistons?

 

[Torinate]

Have you put a bore scope down into the cylinders through the spark plug hole to check for carbon deposits on the pistons?

I have. Pistons and piston walls look great. Tried to take a few pics but they didn’t turn out. Did that last year and again the other day when did the compression test. Not much carbon at all. This is a 16 as well, so no di injectors.

 

[SheepDog]

I have. Pistons and piston walls look great. Tried to take a few pics but they didn’t turn out. Did that last year and again the other day when did the compression test. Not much carbon at all. This is a 16 as well, so no di injectors.

How about fueling issues? BAP wiring issues, dirty filter sock on the pump bucket, loose/damaged fuel line connections, air getting in the lines etc.

 

[SheepDog]

Add pinched or damaged Fuel injector O-rings to that list

 

[Torinate]

Haven’t seen any fueling issues. Afr runs what’s commanded. No knock. Damaged prong should show up on a smoke or would be a fuel smell underhood if leaking out. Fuel trims look the same as when final logs were done after blower install 3 years ago. Funny. Looking back it was May 2020…

 

[Wkbrd2damax]

Following. I have been having a very similar issue with mine over the last couple years thru many modifications. Mine is hesitant when cold and also once it warms up. Also sounds like a miss once it warms. Haven’t been able to narrow mine down either.

 

[Torinate]

Following. I have been having a very similar issue with mine over the last couple years thru many modifications. Mine is hesitant when cold and also once it warms up. Also sounds like a miss once it warms. Haven’t been able to narrow mine down either.

Has it ever thrown a CEL?
Do you hear a popping sound at idle sporadically?
What happens with your hesitation? Do you step on the gas then nothing for a second then goes? It's really frustrating lol!!

 

[Wkbrd2damax]

Yes. Popping sound at idle that is sporadic. Sounds like a sporadic miss. Car has a hesitation when accelerating at the beginning then smooths out and takes off. Does that more when cold than hot but can still feel it once it has warmed up. Has been like that from basic bolt on’s all the way till now with a whipple.

 

[Torinate]

Yes. Popping sound at idle that is sporadic. Sounds like a sporadic miss. Car has a hesitation when accelerating at the beginning then smooths out and takes off. Does that more when cold than hot but can still feel it once it has warmed up. Has been like that from basic bolt on’s all the way till now with a whipple.

Eerily similar...

I'll post a fix when I get there - I would ask you to do the same as well...

Sponsored