Going carb = no optispark
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Going carb = no optispark I've had it with the optispark. This thing is a brand new GM piece with no more than 1K on it. Car was driving fine, and we had some rain here (happens once a year for a week) and some wet roads and a few deepish puddles, and it starts acting up already.
It drives fine when you first start it, then as it warms up or after 20 mins of driving it starts backfiring out the exhaust, sputtering, and missing like crazy. Especially under load.
I remember all these symptoms before replacing the previous one.
I am considering going carb just to get rid of the worst distributor to be ever made, unless I can get a coil pack system and keep the fuel injection part of it.
Rant over
It drives fine when you first start it, then as it warms up or after 20 mins of driving it starts backfiring out the exhaust, sputtering, and missing like crazy. Especially under load.
I remember all these symptoms before replacing the previous one.
I am considering going carb just to get rid of the worst distributor to be ever made, unless I can get a coil pack system and keep the fuel injection part of it.
Rant over
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I turned the car off, back on and I heard a pop as it fired up, but then funnily ran smooth? (crazy LT1s).
Fast forward to today, driving to the mall, all good (no rain today roads dry). Drives ok, get to the mall and then starts to sputter. Its usually doing it in idle in gear or when I'm just about to move and then clears out.
However, on my way back, it drove alright for a few mins and then it starts to sputter in gear, rpms dropping really low, had to throw it in neutral many times and rev it, and it would still drop and not idle. Then as I tried to get her moving on the road to get home it started to back fire and miss heavily.
I really hope its a few ignition cables burned by the headers or something and not the opti. I'm trying hard to save for a stall and don't want to be investing into another opti.
I would rather go carb!
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I will scan for codes and get back to you guys. 5 mins.
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Before throwing the opti under the bus, make sure you dont have bad plug wires. I got some new wires years ago from a vendor on the board (no longer in business) and they were pure junk. Worked great till it rained and the car spit and sputtered and ran like crap.
When the wires were wet there were sparks shooting out of them like the 4th of July. Got new MSD wires and all the problems were gone.
Spray a mist on the wires and watch for sparks and crackling noises. If these effects happen, you need newer lower resistance plug wires.
When the wires were wet there were sparks shooting out of them like the 4th of July. Got new MSD wires and all the problems were gone.
Spray a mist on the wires and watch for sparks and crackling noises. If these effects happen, you need newer lower resistance plug wires.
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This!! ^^^
I bet the % of improperly diagnosed opti failures is WAAAAAYYYYYYYY up there!
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OK, I know I took long but thought I would do some testing myself first.
First thing I did, I reflashed my PCM back to the OEM tune. Believe it or not, no misfiring during driving and ran smooth except in traffic it drove like crap (as expected) but was really weak compared to tuned of course. I even logged the driving on FreeScan (will try to upload it).
Then I stop in a parking lot, and reflash the PCM to the tune I got. Car drove well for a few mins, and then it goes all hay wire. I was logging on DataMaster this time though. It was sputtering like crazy, sounded like it was running on half the cylinders :S even the O2 sensors were reading very far apart. One was 5xx mV and the other 1xxx mV :S
Almost home, I start hearing a ticking from the engine, sounded loud (engine still sputtering). I stopped at the parking lot and popped the hood (it was also struggling to idle), the sound was coming from within the engine, like it was a lifter stuck or something.
I will look for a site that I can use to upload the logs and if any of you guys could look it up.
I kept getting the EST OPEN code but I don't understand how I could get it when my opti is practically new. Knock counts even hit 60,000! WTF?
I am having a really bad day
EDIT: the roads are dry now and there is no rain.
First thing I did, I reflashed my PCM back to the OEM tune. Believe it or not, no misfiring during driving and ran smooth except in traffic it drove like crap (as expected) but was really weak compared to tuned of course. I even logged the driving on FreeScan (will try to upload it).
Then I stop in a parking lot, and reflash the PCM to the tune I got. Car drove well for a few mins, and then it goes all hay wire. I was logging on DataMaster this time though. It was sputtering like crazy, sounded like it was running on half the cylinders :S even the O2 sensors were reading very far apart. One was 5xx mV and the other 1xxx mV :S
Almost home, I start hearing a ticking from the engine, sounded loud (engine still sputtering). I stopped at the parking lot and popped the hood (it was also struggling to idle), the sound was coming from within the engine, like it was a lifter stuck or something.
I will look for a site that I can use to upload the logs and if any of you guys could look it up.
I kept getting the EST OPEN code but I don't understand how I could get it when my opti is practically new. Knock counts even hit 60,000! WTF?
I am having a really bad day
EDIT: the roads are dry now and there is no rain.
Last edited by ADM; Dec 8, 2009 at 04:32 PM.
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Thanks
knock on wood, i've never had an opti problem. think of all the normal people (that dont mess with their cars) driving around their LT1 with MAYBE 1 replaced opti over 100k miles. i personally know of a buick roadmaster with WAAY over 100k miles on the stock opti.
the opti may not be the most robust design, and its not in a great location, but it gets the job done and its not half as bad as people make it out to be.
the opti may not be the most robust design, and its not in a great location, but it gets the job done and its not half as bad as people make it out to be.
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OK, did some data logging again, its a dry sunny day so hoping any moisture should have left our beloved opti.
The passenger side O2 is reading a constant 1097 mV from start up, which looks its not even reading as it seems, but the driver side is reading and fluctuating depending on amount of throttle.
EST OPEN code remains, and so does the tick that sounds like a stuck/collapsed lifter (coming from the intake area). Engine won't even idle, like most of the cylinders aren't even getting any spark.
Will check if all cylinders are getting spark.
The passenger side O2 is reading a constant 1097 mV from start up, which looks its not even reading as it seems, but the driver side is reading and fluctuating depending on amount of throttle.
EST OPEN code remains, and so does the tick that sounds like a stuck/collapsed lifter (coming from the intake area). Engine won't even idle, like most of the cylinders aren't even getting any spark.
Will check if all cylinders are getting spark.
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I think I will be heading towards an EFI 24x conversion kit. Have been looking it up all day long, and have already contacted the makers of the kit. I think I should have invested into this before.
I get to keep my fuel injection, will get 2 new O2 sensors and ready made extensions.
Only problem is it will take 3 weeks to get a harness done for my car (unless they have one in stock).
I get to keep my fuel injection, will get 2 new O2 sensors and ready made extensions.
Only problem is it will take 3 weeks to get a harness done for my car (unless they have one in stock).