LT1 Ignition problem
 

I have been using the Accel DFI gen 7 for 3 seasons now and have never encountered a real problem before. This past season installed a MSD billet distributor on my LT1. When the engine is cold it turns over several times before firing but once fired its OK. The car will run and idol all day as long as you keep the engine running. Once you shut the car off and if any heat is still in the motor (at least recognized by the temp gage) when you go to fire the motor again it turns over really hard, and I have to open the throttle body all the way for it to fire. It idols for several seconds and shuts off. When it shuts off it does not stumble or fade away it just shuts off like a kill switch is being thrown. If you give it any throttle during this brief period of idol the tach needle goes crazy and is not reading true RPM's and then it dies. I have checked ground wires, changed the ECM, changed coils, and changed ignition modules. I have been pulling my hair out, what's left anyway, trying to figure this out. If you can offer any help please do.

Re: LT1 Ignition problem
 

I hate to tell you this, but it sounds like the MSD Optispark-distributor! I have heard of some problems with these units!

Re: LT1 Ignition problem
 

Hello Jason...remember me? I ran the stock distributer...just removed all the optispark stuff and added the MSD cap and rotor. I used a crank trigger and did not feed that trigger signal into the ECU. I ran the timing locked out just for simplicity and ran an MSD digital 6 and also an MSD 7Al2 for a while. I have no experience with the MSD distributer for an LT-1 but it sure does sound like it is the trouble as Woodro says.....

Re: LT1 Ignition problem
 

I've also seen numerous problems like that with the MSD Optispark. I replace the plastic pegs on the stock GM rotor with aluminium 1/8" pop rivets to prevent slinging the blades off the rotor, that is the only problem I ever had with the factory GM pieces. I later went to an MSD crank trigger for the signal and only used the Optispark for the cap and rotor.

Re: LT1 Ignition problem
 

Sorry to say but the MSD piece is junk! I have sold several of these units and 3 out of 5 were screwed right out of the box! QC on these must not exsist!

Re: LT1 Ignition problem
 

Hello Rich I sure do remember you how are you. I should have bought your stocker instead of fiddling with this P.O.S. Anyway I had 1 good run on the car at the grove running 8 tenths under in E weight and I thought I was in the right direction. Then on the second trip to a test and tune this issue turned up just out of the blue. Figuring the MSD was really the only change I had made to the car I sent the distributor back to MSD, almost against thier will, and they said they would replace the optical eye. Got the distributor back and nothing changed so I figured it must have been something else causing this problem. I was not aware of any complaints about this distributor at the time or I would have just put a crank trigger on it to begin with. Thank you guys for taking the time to respond to this thread. I do appreciate it.

Re: LT1 Ignition problem
 

Hello Jason.....My car had an MSD 7AL2 in it when I bought it. My first few runs were ok...after I figured out the firing order mix up....like you had. After a few runs it started to miss real bad over 6000 and the tach would become erratic at the same time it missed. I borrowed a friends box and it ran fine. I sent the box to MSD explaining exactly what it did. They told me they found nothing wrong. I swapped the bpx back in the car at least twice and everytime it missed just like before. I replaced the box and the coil. Went to a MSD Digital 6 and matching coil. Ran fine. My car has changed hands twice. It is still local and the owner is working on the fuel map with someone that is pretty knowledgable. I liked the car but had to sell it for a number of reasons...Good luck with your Camaro. See you maybe at a race somewhere....Rich

Re: LT1 Ignition problem
 

I am glad you guys posted this and also thanks for helping out.I run Jeff Potts old LT1 Camaro it has a old Accel system in it I was thinking of upgrading to new system.Also I think there might be some changes to wireing I need to make.First I know I want to put crank trigger on it also it still uses a lot of factory wireing is there a system that you guys like

Re: LT1 Ignition problem
 

The crank trigger can work with any ECU as far as I know. I had an Accel Gen VII and it has many more features than a racecar needs. I spoke to a few guys when I had my Firebird and Holley ECU's seemd to be the most popular as they were out there a long time and people maybe shared info on their fuel map. I thought about buying a differnt ECU too. I looked at the Fast unit software and it seemd to me that they all did the same thing and one was not way better than another. I needed the help of an experienced "tuner" and the present owner has someone that has a lot of experience with EFI helping him. WOT was fine but other areas were not so good and he cleaned that up quite a bit. I read about sequential versus bank to bank but don't know if it's worth the effort. I ran locked out timing and runnning the crank trigger signal thru the ECU and plotting a timing curve is probably better. I bought a stand alone datalogger and had my ECU upgraded to work with it. I got nowhere with that...wasted money. I used an Innovate LM-1 with the RPM converter to help me get as far as I did and it was a very big help. I knew exactly nothing about an LT-1 and never even looked under the hood of a street car before I did mine. I built the engine and tuned the ECU from scratch by myself. I hated to sell it but really had to. It was a really fun car to drive when it made a good run......

Re: LT1 Ignition problem
 

Try a different opti would me my suggestion. My first MSD opti was installed on my new bracket engine before I went to Tulsa for Ed to tune my car last december. He got it tuned ok but it had a slight high rpm miss that just got worse the first race of the year. It ended up being the optical sensor was bad right out of the box. While it was out to MSD I bought another one so I could continue the racing season and it ran fine untill the rotor button gernaded after about 30 passes. Put the first one back in and the bearing had too much play in it and the rotor rubbed into the cap ruining both the cap and rotor. I now have the second back in the car and ran it the rest of the season and it seems to be doing fine with over 150 passes on it. I am still keeping the other one in the trailer in case it lets go again. MSD has fixed them under warranty everytime so far but I dont know what will happen next time because their warranty is only for 1 year and it is up on one and will be up on the other in april. One thing you might want to check is how long the drive pin is on your cam. I helped a couple of kids here locally get their cars squared away after they installed aftermaket cams and on both of them the drive pin was too long. It ended up pushing too far into the slot in the opti and caused problems for both. MSD fixed thier optis as well even though it was their screw up for not checking to make sure the pin length was right. I cant remember if they had Crane or Comp cam but it was one of them. Like most people I thought I was helping myself and preventing future problems by going to the MSD opti and did not find out untill after my problems were over that they were having problems with them.
Rob