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2.5GT lags on acceleration


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Just to give you a better visual idea.. Here are all your knock events from one 78k log file.. The top table is actual knock events, and the bottom shows the total data points.. Note that 78k is not a lot of data so this is a considerable amount of knock. Any knock over 1.1 load or so is typically a problem. Note also that these knock events are happening despite the ECU pulling max timing from your timing table..

980388186_gt2005knock.thumb.jpg.3e8f65e153e9ea50b3f54bc4672b7e35.jpg

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I guess anything is possible yes. If the car truly drives fine it could be noise causing the ECU to pull all that timing which would in turn make the car run poorly. Check under the hood for anything that could be causing a rattle. I do however have my doubts on this..

 

As for logging, if you feel up to it, do one more short driving log with the following parameters:

 

AF/Correction#1 (2 byte)

A/F learning #1 (2 byte)

AF Sensor # 1

Engine Load

Engine Speed

Ignition Total Timing

Knock Sum

IAM

Feedback knock

Learning knock

Roughness for each cylinder.

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No to the clutch questions. It's an automatic transmission (6 speed, I think?).

 

Here are new logs for short trips with a couple of quick but not full throttle runs.

 

The first log: Engine was cold and I thought running kind of rough. I stopped logging and wrote the file:

 

https://docs.google.com/leaf?id=0B2aEuJiEjv06ZjE4MDgwMDAtZDQyOC00M2MxLTllNjgtYjA0MTgwZWQxN2Nk&hl=en_US&authkey=CK2C9MUE

 

Second log: I sent a "Reset ECU" command, turned off, waited 10 seconds, turned to "On", waited about 5 seconds, started engine and drove off:

 

https://docs.google.com/leaf?id=0B2aEuJiEjv06MzRjMDU4M2QtODFhYi00OGQyLWI5OTctYjhhYjM3YzM2MDhh&hl=en_US&authkey=CJaswvwI

 

 

Third is from Learning View with a drive similar (but not identical) to second log above:

 

https://docs.google.com/leaf?id=0B2aEuJiEjv06ZDkwN2I1MjYtZjllNi00MTZhLTgwYWEtNWEwMmYzYWI1ZGRh&hl=en_US&authkey=CL7ghdwE

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First log is not useful and the 2nd 2 links appear to be the same learning view. The fact that IAM (ignition advance multiplier) is at 0 explains any power loss. Boost control is disabled by the ECU at this point and you're running a failsafe (RICH) fuel table. Worse though is even with IAM at 0 it is pulling as much as 10 degrees in the lower rpms.

 

Still interested in seeing how roughness monitors increment while driving..

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Yeah, your IAM should be 1 but I'm not surprised it's 0, it's pulled so much timing it's not even going to think about advancing it. There's a lot of physical knock with your feedback knock, check around for a loose bolt in the area? I guess that'd be the first thing to check...sometimes loose debris can trip the sensor if it's vibrating near it. Your A/F's look good on the learning view however.

 

-12 of feedback knock, cheeeseee and rice.

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I'm almost wondering if there's a problem with your ECU. You should getting atleast 1 code, lol. Misfires will throw codes, sometimes phantom misfires won't but judging by the amount of cyl 4 misses there are- I'd suspect a code.... and there weren't any codes before you reset the ECU?
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I'm almost wondering if there's a problem with your ECU. You should getting atleast 1 code, lol. Misfires will throw codes, sometimes phantom misfires won't but judging by the amount of cyl 4 misses there are- I'd suspect a code.... and there weren't any codes before you reset the ECU?

 

This was the first time I used Learning View, so I can't say for certain about before.

 

However, everyone who has worked on this problem has commented that there were no codes thus adding to the confusion about what was happening.

 

I'll try again later after the car has been driven for a bit.

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I'm not sure what is going on but I suspect something mechanical. I will add that my car pulled similar timing when my engine went. In my case it was accompanied by considerable engine noise. At no point in time did my car throw a code either despite total engine failure.
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I'm not sure what is going on but I suspect something mechanical. I will add that my car pulled similar timing when my engine went. In my case it was accompanied by considerable engine noise. At no point in time did my car throw a code either despite total engine failure.

 

 

Valid point, engine mechanical noise, I.E. tapping/knocking can trigger a knock sensor and in turn retard timing. However the OPmeister said his engine sounds fine.

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Maybe this is kind of silly, but I used my phone's voice recorder to record several seconds of engine sound. It is an .amr file and needs to be played using the QuickTime player. I can look into converting it to an .mp3.

 

https://docs.google.com/leaf?id=0B2aEuJiEjv06MjRjMTYyNTAtNGMwNy00NGE2LTliNmYtMTkxYzc0NjViMmRi&hl=en_US&authkey=CIOewqMJ

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I just read this thread, I have the identical symptons with my car, going thru the same exact thing. Had one cylinder 9 psi low, all others normal. Some days it won't even happen other days its terrible. The hotter it gets the better it runs odly enough? Threw a code for the first time this week twice for bad o2 sensor/circuit. Have not had a chance to change it yet. I feel like its not the issue tho. I wanna drive it off the bridge at times!
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