!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!heeeeelllppp!!!
#32
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i tried re-adjusting them last night...still missing...im going to take the intake off tomorrow to get a better look, ive been meaning to do the intake leak fix anyway.
#34
Well if all else fails take it to someone who is certified. Or atleast get a second opinion on it other than yourself. madz28 did your tune so I'd be in contact with them right now.
I have a buddy who graduated Wyotech who I always bother about random things with my car, all it usually takes is a case of beer to get the insight I need.
I have a buddy who graduated Wyotech who I always bother about random things with my car, all it usually takes is a case of beer to get the insight I need.
Last edited by Kaj; 03-09-2008 at 05:29 PM.
#35
The LT1 uses a reluctor wheel driven off the cam and a dual optical pickup to send timing information to the ecm. low resolution is cylinder specific information. 8 pulses, 1 per cylinder with differing pulse width to identify individual cylinders. High resolution signal is 360 pulses evenly spaced for accurate engine speed and a reference for cylinder identification. When the knock sensor detects a misfire, it uses the low resolution cylinder identification signal to determine which cylinder is affected.
This is the "opti" portion of the optispark.
This is the "opti" portion of the optispark.
And, the PCM does not use the knock sensor to identify a misfire. The CKP sensor was added to the 96/97 engines to meet the OBD-II requirement for misfire detection. The PCM monitors the crank rotational speed data from the CKP sensor, and compares it to the know irregularities in the crank rotational velocity due to the impulses of the individual cylinders firing. When the PCM sees a rotational velocity pattern that does not match the known pattern, it counts it as a misfire. As a result, you can get false misfire data, due to crank rotational irregularties caused by an aftermarket cam, or even a rough road.
#36
The reluctor wheel is on the crank and is not used for timing info. There is no reluctor wheel on the cam... only the optical pickup. If the reluctor was required for timing info, the 93-95 engines wouldn't run, because they don't even have CKP sensor. The PCM gets all the info it needs from the high resolution and low resolution optical signals.
And, the PCM does not use the knock sensor to identify a misfire. The CKP sensor was added to the 96/97 engines to meet the OBD-II requirement for misfire detection. The PCM monitors the crank rotational speed data from the CKP sensor, and compares it to the know irregularities in the crank rotational velocity due to the impulses of the individual cylinders firing. When the PCM sees a rotational velocity pattern that does not match the known pattern, it counts it as a misfire. As a result, you can get false misfire data, due to crank rotational irregularties caused by an aftermarket cam, or even a rough road.
And, the PCM does not use the knock sensor to identify a misfire. The CKP sensor was added to the 96/97 engines to meet the OBD-II requirement for misfire detection. The PCM monitors the crank rotational speed data from the CKP sensor, and compares it to the know irregularities in the crank rotational velocity due to the impulses of the individual cylinders firing. When the PCM sees a rotational velocity pattern that does not match the known pattern, it counts it as a misfire. As a result, you can get false misfire data, due to crank rotational irregularties caused by an aftermarket cam, or even a rough road.
Alot of people here know this info, but i ALWAY see you going to details with every post!
#37
The reluctor wheel is on the crank and is not used for timing info. There is no reluctor wheel on the cam... only the optical pickup. If the reluctor was required for timing info, the 93-95 engines wouldn't run, because they don't even have CKP sensor. The PCM gets all the info it needs from the high resolution and low resolution optical signals.
And, the PCM does not use the knock sensor to identify a misfire. The CKP sensor was added to the 96/97 engines to meet the OBD-II requirement for misfire detection. The PCM monitors the crank rotational speed data from the CKP sensor, and compares it to the know irregularities in the crank rotational velocity due to the impulses of the individual cylinders firing. When the PCM sees a rotational velocity pattern that does not match the known pattern, it counts it as a misfire. As a result, you can get false misfire data, due to crank rotational irregularties caused by an aftermarket cam, or even a rough road.
And, the PCM does not use the knock sensor to identify a misfire. The CKP sensor was added to the 96/97 engines to meet the OBD-II requirement for misfire detection. The PCM monitors the crank rotational speed data from the CKP sensor, and compares it to the know irregularities in the crank rotational velocity due to the impulses of the individual cylinders firing. When the PCM sees a rotational velocity pattern that does not match the known pattern, it counts it as a misfire. As a result, you can get false misfire data, due to crank rotational irregularties caused by an aftermarket cam, or even a rough road.
Having a reluctor wheel doesn't mean that it's a magnetic pickup. It can be high and low spots on the outside of a ring or holes that do or do not allow inferred light to pass through. Both will send out a digital high or low.
I do stand corrected on the OBD1 vs OBD2 and individual cylinder ident for misfire. I'd forgotten that OBD1 ecms don't have a provision to tell the difference.