Intermittent issue - boost, misfire, temperature

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kryptto

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@Ta2dResqr ever dream of those bigger XDI injectors to go with that fuel pump? :(

 

Ta2dResqr

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@Ta2dResqr got ya buddy. See attached

Volt and ohms
Is that All Data? Looks like same format. I was looking at 2015 and it said 11-18 ohms. I ended up swapping injectors front to rear. (1 to 4, 2 to 5, 3 to 6). Problem stayed with #3.

I put the MSD #3 coil on a spark tester and plugged it in to the coil connector. O had hood consistent spark.

I am assuming I am getting injector pulse because that cylinder was wet and fouled. I suppose all I have left to do is a compression/leak down test.

Outside of a mechanical issue with cylinder #3, I have no ideas. A computer issue has crossed my mind with it acting up worse when the temperature gauge drops. The fact that it always drops to a flat 149 and it is almost instant and when it goes away, it jumps right back to mid range is why I am wondering about it. I checked all the harnesses I could while the intake was off.
 

Ta2dResqr

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@Ta2dResqr ever dream of those bigger XDI injectors to go with that fuel pump? :(

I have but with moving injectors and the problem not moving, I am afraid I may end up needing a motor. Swinging that on jackstands with no motor lift may not be an option. Especially this time of year in Ohio with a Harley as my backup mode of transportation.
 

Ta2dResqr

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Drove it to work this morning. It was acting up at idle. When I got to cruising speed it acted up until it got warm. When I got on the freeway and to cruising speed it started acting up again. I put it in Sport mode and dropped it to 5th gear. I drove the whole way to work without the light coming on or a noticeable miss. As soon as I got back to idle in the parking lot, it started acting up again.

Last thing I got is compression/leak down test. Guess I keep pushing it off because it is an expensive, time consuming repair if needed. After that, i will be down to electronic intermittent issues.
 

kryptto

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After that, i will be down to electronic intermittent issues.
Wiggle test the harness to see any variance in that injectors readings? That was an interesting test. Sorry to hear the frustration.
 

Ta2dResqr

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Well, either dropped a turbo or motor on the way to work. Stopped at the security shack to get on property and the car stalled. Started it back up and blue smoke everywhere. 2500+ rpms it seems fine. No smoke, no miss. Go below that and it turns into a smoke show. Hoping I can limp her home and start tearing it apart. Turbos are 6 month old TurboBay rebuilds. Last weekend, there was not much oil in the intercooler. Smoke is coming out both tailpipes but with the common 3rd cat, I don't know if I can use that in diagnostics. When I lost the rear turbo, only 1 side smoked. Not sure if I will part out the mods to pay for a motor or what. Find out more when I get home and tear it apart this weekend.
 

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SHOdded

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i have factory manuals to use for my posts.

i would suspect the turbobay rebuilds. post pandemic, quality on stuff has really dropped, not to say these folks had quality stuff before lol.

pcv could always be an issue but otherwise the smoke is usually from turbo failure.
 

Ta2dResqr

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i have factory manuals to use for my posts.

i would suspect the turbobay rebuilds. post pandemic, quality on stuff has really dropped, not to say these folks had quality stuff before lol.

pcv could always be an issue but otherwise the smoke is usually from turbo failure.
I was too depressed this weekend to even mess with the car. Turbos would be awesome because they have a 2 year warranty. Motors look like they are going for $3k-6k right now.
 

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i have not seen motors go on the SHO except in WOT situations in subfreezing temps, when engine temp was not uptospec.

the Flex however, for whatever reason, i have seen a few blocks getting windowed.

return whatever you can to stock, make sure the tune is appropriate, and reevaluate. we have occasionally seen the pcm get bricked, not sure after how many tuning cycles, but iirc more common on 2013+ - as are ptu and rdu failures.

on the 2015, weird issues were caused by loose oem wiring connections at the vct solenoid, can't say that is your issue, but might as well check for similar culprits throughout the bay.

yeah tracking down these gremlins can be depressing with the sheer amount of mechanical and electrical elements involved. just when you think you know it all, 15 years down the road, there's always one more. hang in there.
 

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Well, finally got around to a compression test. 150 psi on cylinder 6 (for a comparison), 0 psi on cylinder 3. It moves the needle off the resting pin and releases a tiny pressure when purging the gauge.
 
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kryptto

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Well, finally got around to a compression test. 150 psi on cylinder 6 (for a comparison), 0 psi on cylinder 3. It moves the needle off the resting pin and releases a tiny pressure when purging the gauge.
Ughhhhh

I get a mental image of Lucy pulling the football from Charlie last second l, ifl you don't get the joke done ask I am aging myself....
 
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