Super sluggish off the line - 94Z
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Joined: Apr 2010
Posts: 92
From: Fairfield, PA
Yes... the Optispark is the distributor. The front half has the conventional high voltage spark distribution - cap and rotor. The back half includes an electronic optical pickup for cam position. It sends cam position to the PCM so the PCM can time the spark and the sequential fuel injection. If you have a problem with the optical cam position sensor, it will set codes... but those codes don't turn on the SES light, so you don't know they are there unless you scan it. If the cap/rotor has issues - moisture, carbon tracking, burned contacts, etc. it will not set any codes. It will be down on power and will typically misfire. The 96/97 cars have misfire detection via OBD-II and the added crank position sensor, but the 93-95 OBD-I cars do not include misfire detection.
A missing muffler should not reduce power or torque on a fuel injected engine. In effect, what you are saying about the lack of a muffler causing it to have "no bottom end" might be true on a carb engine, where the improved volumetric efficieny has not been addressed by rejetting the carb. But on an EFI engine, the PCM is fully capable of adjusting for improved breathing (VE). In effect, if lack of a muffler cost bottom end, opening a cutout would be a disaster. It isn't.
A missing muffler should not reduce power or torque on a fuel injected engine. In effect, what you are saying about the lack of a muffler causing it to have "no bottom end" might be true on a carb engine, where the improved volumetric efficieny has not been addressed by rejetting the carb. But on an EFI engine, the PCM is fully capable of adjusting for improved breathing (VE). In effect, if lack of a muffler cost bottom end, opening a cutout would be a disaster. It isn't.
Thanks for the explanation of the optispark.
Actually, I didn't bring up the lack of a muffler issue. That was Brucer on post#6.
Greg
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From: Hell was full so they sent me to NJ
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Joined: Dec 2008
Posts: 437
From: ABQ, NM
Yes... the Optispark is the distributor. The front half has the conventional high voltage spark distribution - cap and rotor. The back half includes an electronic optical pickup for cam position. It sends cam position to the PCM so the PCM can time the spark and the sequential fuel injection. If you have a problem with the optical cam position sensor, it will set codes... but those codes don't turn on the SES light, so you don't know they are there unless you scan it. If the cap/rotor has issues - moisture, carbon tracking, burned contacts, etc. it will not set any codes. It will be down on power and will typically misfire. The 96/97 cars have misfire detection via OBD-II and the added crank position sensor, but the 93-95 OBD-I cars do not include misfire detection.
A missing muffler should not reduce power or torque on a fuel injected engine. In effect, what you are saying about the lack of a muffler causing it to have "no bottom end" might be true on a carb engine, where the improved volumetric efficieny has not been addressed by rejetting the carb. But on an EFI engine, the PCM is fully capable of adjusting for improved breathing (VE). In effect, if lack of a muffler cost bottom end, opening a cutout would be a disaster. It isn't.
A missing muffler should not reduce power or torque on a fuel injected engine. In effect, what you are saying about the lack of a muffler causing it to have "no bottom end" might be true on a carb engine, where the improved volumetric efficieny has not been addressed by rejetting the carb. But on an EFI engine, the PCM is fully capable of adjusting for improved breathing (VE). In effect, if lack of a muffler cost bottom end, opening a cutout would be a disaster. It isn't.
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Joined: Jan 2010
Posts: 274
From: western ky
injuneer,
i understand what your saying about the muffler, i would suspect the same, especially with the computer coming into play...
i do know when i purchased the car, the previous owner had no muffler on the car, it was loud and obnoxious, and the car seemed sluggish and didnt have any power off idle... i bought a flowmaster (not the best muffler i know) for $30 that was my first mod.. had the muffler installed and i could tell the difference as soon as i took off from the muffler shop.. i could easily tell the difference in torque off idle... i think the lack of muffler, along with my stock 2.73 gears was the culprits causing it, it had to be, because that was all that had been done to the car was the addition of the muffler...
thinking my next mod is going to be dropping the flowmaster in favor of a 3 or 3 1/2 inch cat back single perforated core turbo muffler... i need tires first though..
i understand what your saying about the muffler, i would suspect the same, especially with the computer coming into play...
i do know when i purchased the car, the previous owner had no muffler on the car, it was loud and obnoxious, and the car seemed sluggish and didnt have any power off idle... i bought a flowmaster (not the best muffler i know) for $30 that was my first mod.. had the muffler installed and i could tell the difference as soon as i took off from the muffler shop.. i could easily tell the difference in torque off idle... i think the lack of muffler, along with my stock 2.73 gears was the culprits causing it, it had to be, because that was all that had been done to the car was the addition of the muffler...
thinking my next mod is going to be dropping the flowmaster in favor of a 3 or 3 1/2 inch cat back single perforated core turbo muffler... i need tires first though..
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