Any LT1 guys left in Houston?
#1
Any LT1 guys left in Houston?
I think my opti is going out but I want to be 100% sure before I pull it. I'm just not sure if the symptoms I have are accurate for an opti dying or if it's something else. When my first opti went out it didn't do anything like it's doing now.
#4
Well, I still have a set of cast iron heads lying around. And I still have the inverted Torx tool (E4?) for disassembling the OptiSpark. I'd bet the Harmonic Balancer still has quick-removal capabilities, too. I think I have a water pump I saved to (maybe) upgrade to electric.
But, NO!...I've moved to LSx's...
-KP
But, NO!...I've moved to LSx's...
-KP
#5
#6
More info would help. How many miles on that opti? How long has it been doing it? Does it feel like you're hitting a rev limiter (not THE limiter, just does it feel like that)? What brand opti is in there?
Make sure it's not fuel by checking fuel pressure, and start with inspecting all the plug wires for damage/burns/breaks. Also watch the engine at night and look for spark arcing out the wires. Make sure your plugs aren't fouled. You want to eliminate all the small stuff before doing the opti. Too many of them are misdiagnosed, and it just costs you time and money.
Make sure it's not fuel by checking fuel pressure, and start with inspecting all the plug wires for damage/burns/breaks. Also watch the engine at night and look for spark arcing out the wires. Make sure your plugs aren't fouled. You want to eliminate all the small stuff before doing the opti. Too many of them are misdiagnosed, and it just costs you time and money.
#7
More info would help.
How many miles on that opti? Approx 15k
How long has it been doing it? 3 months/approx 1200 miles
Does it feel like you're hitting a rev limiter (not THE limiter, just does it feel like that)? It feels like all the timing is getting snatched out on a ramp as I accelerate from any rpm in any gear(timing verified not getting pulled out)
What brand opti is in there? Delco
Make sure it's not fuel by checking fuel pressure, Tested good last week
and start with inspecting all the plug wires for damage/burns/breaks. Brand new wires checked and wrapped
Also watch the engine at night and look for spark arcing out the wires. No burns that I have seen. I burned a full set up before I got this new set and wrapped them in high temp wrap. No issues since.
Make sure your plugs aren't fouled. Brand new plugs with less than 500 miles. Last set came out perfectly clean
You want to eliminate all the small stuff before doing the opti. Too many of them are misdiagnosed, and it just costs you time and money.
How many miles on that opti? Approx 15k
How long has it been doing it? 3 months/approx 1200 miles
Does it feel like you're hitting a rev limiter (not THE limiter, just does it feel like that)? It feels like all the timing is getting snatched out on a ramp as I accelerate from any rpm in any gear(timing verified not getting pulled out)
What brand opti is in there? Delco
Make sure it's not fuel by checking fuel pressure, Tested good last week
and start with inspecting all the plug wires for damage/burns/breaks. Brand new wires checked and wrapped
Also watch the engine at night and look for spark arcing out the wires. No burns that I have seen. I burned a full set up before I got this new set and wrapped them in high temp wrap. No issues since.
Make sure your plugs aren't fouled. Brand new plugs with less than 500 miles. Last set came out perfectly clean
You want to eliminate all the small stuff before doing the opti. Too many of them are misdiagnosed, and it just costs you time and money.
Trending Topics
#11
Cats are gone. O/R Y. The o2s are brand new but I will pull them and check them again. Hopefully I come to a resolution today good or bad. Tired of messing with it. I'd like to just drive.
#13
Also eliminate the rest of the ignition system.
http://shbox.com/1/coil_testing.jpg
http://shbox.com/1/4th_gen_tech2.html#opti_test
#15
Car is a 94.
I have checked the opti harness as well as the ICM harness both are dead on spec. The o2s are bosch; brand new with less than 1k miles on them. They alternate between maybe 80 and 860 mV. I was told they are supposed to vary that much. I'm not sure if they're supposed to do it simultaneously but they tend to alternate with one being high and one being low.
I checked and cleaned the IAC yesterday as well as the TB. Put it back on and all the symptoms persisted:
-rough idle[idle goes as low as 475 during logging while in gear and quickly attempts to recover to 550 where it's supposed to be],
-power through all rpm ranges above 2000 greatly reduced
-vibration that I can feel through the pedal almost on a loop
-intermittent backfiring
One thing I heard yesterday as I left it running right before I put a gun in my mouth was some kind of popping that almost sounded like arching so today I'm going to ****** the alternator and alternator bracket and pull all the plugs and wires. I'll ohm out all the wires to be sure it's not those for the 3rd time.
I have checked the opti harness as well as the ICM harness both are dead on spec. The o2s are bosch; brand new with less than 1k miles on them. They alternate between maybe 80 and 860 mV. I was told they are supposed to vary that much. I'm not sure if they're supposed to do it simultaneously but they tend to alternate with one being high and one being low.
I checked and cleaned the IAC yesterday as well as the TB. Put it back on and all the symptoms persisted:
-rough idle[idle goes as low as 475 during logging while in gear and quickly attempts to recover to 550 where it's supposed to be],
-power through all rpm ranges above 2000 greatly reduced
-vibration that I can feel through the pedal almost on a loop
-intermittent backfiring
One thing I heard yesterday as I left it running right before I put a gun in my mouth was some kind of popping that almost sounded like arching so today I'm going to ****** the alternator and alternator bracket and pull all the plugs and wires. I'll ohm out all the wires to be sure it's not those for the 3rd time.
#16
In an earlier post you stated it wasnt backfiring. To be clear it is backfiring? In my opinion that changes the hunt up a bit. Its apparent you have an ignition issue but Im still not sold on the opti just yet. Let us know what you find after the plug and wire inspection.
#18
In an earlier post you stated it wasnt backfiring. To be clear it is backfiring? In my opinion that changes the hunt up a bit. Its apparent you have an ignition issue but Im still not sold on the opti just yet. Let us know what you find after the plug and wire inspection.