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Discussion Starter · #1 ·
Friends please help me with my problem.
I began to feel a strong loss of power from 1500 to 2500, this happens when the motor is not heated to 85 degrees Celsius, as soon as it heats up everything passes and the car goes ok.
I connected my HP tuner and recorded the logs, I was surprised when I saw that a knocks appears in this range.
Sensor No. 1 shows that the voltage on it starts to rise to 4 volts, as I understand it on the left side of the engine, everything passes above 3000 rpm, no knocks.
I changed the knock sensors, I changed the oxygen sensors, the problem remained
I don't know what to do anymore.
 

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JGC Srt8 2014
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Friends please help me with my problem.
I began to feel a strong loss of power from 1500 to 2500, this happens when the motor is not heated to 85 degrees Celsius, as soon as it heats up everything passes and the car goes ok.
I connected my HP tuner and recorded the logs, I was surprised when I saw that a knocks appears in this range.
Sensor No. 1 shows that the voltage on it starts to rise to 4 volts, as I understand it on the left side of the engine, everything passes above 3000 rpm, no knocks.
I changed the knock sensors, I changed the oxygen sensors, the problem remained
I don't know what to do anymore.
Hi there,
Forged engine internals? (Rods and Pistons)
 

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JGC Srt8 2014
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I have similar issue but with forged engine and custom exhaust. Tried to dial in with HPT and the their forum (some guys are quite helpful there). Managed to reduce the retard significantly but not to get rid of. They say that Mahle pistons are very noisy, so I live with that. Once the engine warms up - retard is zero. But that obviously is not your case.
 

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Well, if it does not exist when engine warms up - I'd say that is not. Try using better petrol and (98 or 100) and see if retard is lower. If it's the same - most probably it is not a real knock. As far as I understand the principals ))
 

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Pull spark plugs and compare.

Also post your log, might be too much ignition advance. Some parameters increase timing like low intake air temperature and low engine coolant temperature. And I wouldn't drive hard before the engine warms up anyway.
 

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the logs of mine are below - with cold engine and huge retard, after warm up without. all done with same conditions - start from a complete stop under very mild throttle.

can only post pics, attachements as *.txt or graphic files are only allowed, that is what TS is writing about.

Font Line Rectangle Screenshot Parallel


ps: topicstarter, I hope you do not mind I interfere in your thread? the problems seem to alike even though the engines are different (stock/modified)
 

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Discussion Starter · #16 ·
he logs of mine are below - with cold engine and huge retard, after warm up without. all done with same conditions - start from a complete stop under very mild throttle.
and during the knock, what is the voltage on knock sensors 1 and 2? My voltage on knock sensor 1 rises to 4 volts and on knock sensor 2 does not reach 1 volt
 

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the logs of mine are below - with cold engine and huge retard, after warm up without. all done with same conditions - start from a complete stop under very mild throttle.

can only post pics, attachements as *.txt or graphic files are only allowed, that is what TS is writing about.

View attachment 233071

ps: topicstarter, I hope you do not mind I interfere in your thread? the problems seem to alike even though the engines are different (stock/modified)
Ok I believe this is definitely true knock, because the knock sensor voltages are normal after warm up.
6.4s are known for low speed knock but this is too much 9° at 21% TPS is not normal.
1-2° short term knock is normal with initial tip in, and between shifts at WOT.

Do you have a tune? If yes, send me a link to your HPT post I'll go take a look.
 
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