78 SC Ignition or Fuel???

MikeD48082 · 07-30-2004, 06:35 AM

This past weekend I decided to take my SC for it's first long trip since I have owned it. The car ran great for approx. 30 miles until I hit stop and go traffic. It did not overheat, however after about 20 min. in traffic it just died. As it was sputtering and backfiring, I managed to get it fired up and off of I-75. After letting the car sit for 30 min., as I was waiting for a tow, It fired right up and ran great. I have driven it short distances 3 times since with no problems. Any suggestions on where I should start???

Thank you.

jpnovak · 07-30-2004, 06:44 AM

There have been some recent posts about the CDI and coil failures in the heat. Try the archives for CDI, failure*, coil*, etc.

If you have the stock Bosch CDI it is likely fine. I would suspect bad contacts, a slowly dying coil or a bad transmission ground strap.

rlane · 07-30-2004, 09:19 AM

I agree, but if you have the Bosch 6 pin acquire a second working one as "even" the Bosch boxes fail. I found it cheaper to convert to MSD and carry a spare but IF I had it to do over I would pay one of our fellow Pelicanites to redo the Bosch box and get a used spare.
My failure description was the same as yours but I ignored it, drove it 250 miles to a DE and it failed on the ride out to the track Sat morning!!!

MikeD48082 · 07-30-2004, 10:53 AM

My PO installed a PermaTune Ignition box. Are you suggesting I switch to the Bosch or the MSD???

rlane · 07-30-2004, 11:12 AM

It was a Permatune that failed in mine, they have a pretty bad reputation around the forum for doing just as you described.
In order of preference I think opinion has moved back to getting someone to rebuild your Bosch or obtaining a rebuilt (Pelican has them and if you do a search you can find a member who does rebuilds) then using MSD 6 AL's then Permatune.

rlane · 07-30-2004, 11:24 AM

It was a Permatune that failed in mine, they have a pretty bad reputation around the forum for doing just as you described.
In order of preference I think opinion has moved back to getting someone to rebuild your Bosch or obtaining a rebuilt (Pelican has them and if you do a search you can find a member who does rebuilds) then using MSD 6 AL's then Permatune.

Early_S_Man · 07-30-2004, 11:27 AM

Mike,

What ambient and engine oil temp when the failures occured? Permatunes have a reputation of late for being temperature-sensitive -- intermittent! Some on the board have them and aren't experiencing any problems.

What condition is the green coax signal cable coming out of the distributor in? If it is cracked or turning brown, it needs to be replaced, pronto, as it can also cause intermittent ignition problems!

MikeD48082 · 07-30-2004, 11:49 AM

Richard, Thank you very much for your help!!!

In reply to Warren, It was about 80 degrees, and the oil temp was about 3/4 on my "idiot" gauge. So, your description makes alot of sense... I will check all my connections, and probably try and locate a rebuilt Bosch unit.

Thanks again, guys

rlane · 07-30-2004, 03:41 PM

Warren as always points out the important thing, that green trigger wire is a good idea, our host sells them and I can tell you mine was really ratty. It has a shield/ground that seems to take a lot of abuse. Permatune does have some diagnostic info on their website and mine in fact did turn out to be a failure.Oh..and invest in the oil temp gauge upgrade/retrofit our host sells...my non numerical guage in the 78SC was reading HOT when in fact on the new gauge ..and with a temp sensor it was probably 30 degrees off