I recently replace plugs and wires on my stock lt1, i switched to the MSD 8.5mm super conductor wires. Now my problem is that it starts up fine and runs fine in park and nuetral, but when put in any gear it sputters. Could this be a swithced wire on the optispark? No CES codes either
Try running the engine again. Make sure (....gas tank is over 10% full and .. oops probably not pertinent to a 95 or 96) that you keep the throttle steady for a few seconds at least. That way any misfire codes that might be pending will get set. It takes at least two ignition cycles to set the MIL for misfire codes.
Ok ill try running it again. I was burping the coolant system since i replaced radiator, started and shut it off mulitiple times. Will it throw a code if it is misfiring?
Those readers are great... but somewhat limited. Consider two other possible ways to go:
1. If you use a smart phone, get a $20 Bluetooth OBD2 adapter (http://www.amazon.com/Elandpower-Bluetooth-Scanner-OBDII-Diagnostic/dp/B004B7YXOM/ref=pd_sim_auto_2) and download the Torque app ($5), or
2, If you have a laptop PC, get a $15 USB adapter (http://www.amazon.com/HDE-ELM-327-Diagnostics-Cable/dp/B004B7PSA0/ref=pd_sim_auto_5) and use a "free" app like OBDWiz or mine (GDScan) and do the same on a much larger screen.
Either way will give you way more information than a simple code reader. For example, you will get misfire counts by cylinder# even when there are not enough to light the MIL. Also graphs, virtual gauges (not on mine), and data logging.
Nice to know. So if the codes come up as example " cylinder 8 and cylinder 6 misfiring" Would that just simply state that the wires are put on backwards on the optispark?
"Multiple misfires" doesn't help much. Can you access the misfire count by individual cylinder? That's where you find out if it's truly random, or related to one or more cylinders - e.g. cross-firing plug wires.
No. The wires were all correct. Can you show me a pic of how you routed the msd 8.5 wires? I have them running through the same "hell hole" as the stock one
My guess is that one or more wires are DOA, or that one or more terminals aren't pushed in/on all the way. BTW, when I was testing my OBD scanner software, I unplugged one wire to force the cylinder#1 misfire code and the engine idled pretty much normally also.
Checked all the wires on both sides, and all of them were connected properly. It ran fine, but as the more i drove it the worse the sputtering came back. Next thing i know the CEL light was flashing then stayed on. Could it be the gap on the plugs that can cause the P0300 "multiple misfire" code? What is the correct gap to be set at .50?
Not sure if it applies on the older cars like ours but its worth a shot, disconnect the battery and while the battery is disconnected clean the throttle body and blade then reconnect the battery and let it idle with the a/c off for a few minutes. A lot of newer vehicles require this as part of the spark plug replacement.
I've tried that. Im thinking it could be the gap, but then again the E3 plugs you cannot gap. Everything ran fine before i changed out the plugs and wires. I never had any codes or problems with the EGR valve or any vacuum leaks.
When I changed the plugs and wires on mine I spun the wire the wrong way and burned it on the header and had a p300 code for the #4 and #8, changed those wires and all fine. But the saving grace was the misfire count feature. On a older bird I had the MSD 8.5mm wires and they worked pretty bad, ran a 8mm set from Autozone and it ran perfect. The other thing to check is if the coil wire is all the way on and if the coil is working properly. I just had to change mine last week for the same issue you are having. $60.00 at Bennett for the AC Delco unit with a 1 year warranty.
I'll check that tomorrow, as far as right now im a little too pissed to work on a car and break something. I'll tackle it when i have a little more patience.
Ya i think i'll have more than one, while i sit and stare at the scars on my hands from trying to reach the plugs on the passenger side. Maybe a beer and a prozac haha
A buddy of mine tried the Bosch multi-electrode plugs in his LT1 and hated them. Best way he could describe them is "funky". Replaced them with conventional plugs and it ran great. The E3 plugs are "gimmick" plugs, just like the Nology "silver" core plugs.... a huge waste of money, with no measureable performance gains. And as you can see, may even involve a degradation of performance. They don't offer anywhere near enough variations in plug heat range, dimensions, etc. to correctly match the plugs specified for every possible engine, so they offer a few choices, and use them in way too many variations of engines, some of which they are simply not correct for.
That's what im starting to wonder. But they wouldn't throw that P0300 code, but then again everything was kosher before i put those plugs in. It almost sounds like the car has a small mild cam when running. Which are best bang for your buck plugs? Not trying to spend another 5.99 per plug
Just get the correct NGK Iridium plugs.... TR55-IX I believe. They may cost more, but the last wayyyyyy longer, holding the recommended 0.050" gap. That's why the factory installed platinum plugs - so they could provide a 100,000 mile emissions guaranty with no parts replacement. Iridium is a step up from platinum. Yes, a $2 conventional, non-precious metal plug will be cheaper, but it may only last 15-20K miles, the gap will open up, and then you'll be back under the hood scraping your knuckles.
I run conventional plugs, but only because nitrous does not play well with the platinum plugs, and I have to pull them regularly to check for signs of detonation, so it's no big deal to put a new set in every once in a while.
It's also possible that one is loose, or that you cracked a porcelain insulator while installing them.
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