Help with Code 16-Low Resolution Pulse
Thread Starter
Advanced
Joined: Oct 2009
Posts: 67
Likes: 16
From: Lancaster, Pa
Help with Code 16-Low Resolution Pulse
I have a '92 with LT1 and keep getting a code 16 after car gets warm. Sometimes it won't start after it is warm and has sat for a few minutes. It will turn over with starter, but, will not fire. After a while, it cools and starts right up. When this happens, I get the code 16. At times, it will stall at driving speeds and when I pull over, it will usually start within a couple minutes. I also get a code 16 when this happens. It has not stranded me yet, but, I don't trust it these days. Previous owner installed MSD opti about 1000 miles ago, but, it is now out of warranty. I have tried troubleshooting as per the service manual, but, the MSD has a hard wired distributor connection, so no plug to disconnect at the opti. I can only check voltage at the test connector by the fuel rail. I get no spark and no injector pulse as the ECM is not recognizing the low pulse and cuts out spark and fuel.
Is my problem in the distributor? Do I need a new one already? Has anybody else had this happen? Thanks for any advice!
Is my problem in the distributor? Do I need a new one already? Has anybody else had this happen? Thanks for any advice!
Team Owner
Joined: Feb 2006
Posts: 23,192
Likes: 117
From: San Antonio Texas
MSD's opti is built like a tank. Too bad they filled it with cheap, slow responding photocells that barely make it through the warranty period. Looks like you (also) got one of their turkeys. It seems to be hit or miss with them. You either get one that is super great or you get one with borderline electronics. At that price they should test EACH Opti before shipping it and include the data sheets in the box. Maybe that way they would have a more dependable product that you wouldn't have to buy two of just to get one good one.
Le Mans Master
Joined: Mar 2001
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From: Life is just one big track event. Everything before and after is prep and warm-up and cool-down laps
Cruise-In III Veteran
Cruise-In IV Veteran
St. Jude Donor '12
Yep its OPTI time. Good news is that its been done once so its just a day of work in the garage.
Tech Contributor
Joined: Aug 2006
Posts: 9,933
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From: Peoria Arizona.. Resident Gold Cylon
Replace your Opti. May want to look at replacing the water pump at the same time. Make sure the new replacement Opti is the newer vented style if you decided to revert to OEM. GC
Instructor
Joined: May 2009
Posts: 110
Likes: 1
I also got a dud from MSD , mine didnt make 2 weeks. couldnt get warrenty cause i threw out bill.cant afford new one and labour charges.THAT WAS LAST YEAR. oh ya,almost forgot ,mine didnt come with a rotor!!! had to order that too. wont be replacing it with a msd thats for sure.
Thread Starter
Advanced
Joined: Oct 2009
Posts: 67
Likes: 16
From: Lancaster, Pa
Thanks for the replies, everyone. I called MSD and spoke to a tech and he told me it was most likely the opti low pulse sensor gone bad. I got a new MSD opti and put it in this weekend by myself. For a weekend wrench turner, I didn't do too bad. It took me about 6 hours when all said and done. I was very careful with both the removal and install of the new one. Car runs fine now with none of the previous symptoms. I am sending the old one back to MSD to have it rebuilt for around $100. I will keep it as a spare for my '93 when it gets sick. Thanks everyone.
