Alright, ill start by what the car is doing. Its an 88 350tpi, it doesnt seem as torquey as before (seems to get worse the more it warms up), it will stall at random times (under throttle and at idle) and my idle fluctuates pretty noticably.

I installed an aftermarket tach, and the needle is constantly shaking. Its not a smooth motion as it revvs, it seems to jump around. My old stock tach didnt work at all, so im not sure if thats the engine acting weird or the tach acting wierd. I boight the tach from a friend, and he said it worked great for him. I thought it may have been a vacuum leak but i checked my vacuum and it was great, right where it should have been. TPS is set right at 54v and climbs smoothly as it should.

The car isnt nearly as torquey as before, and ive been having a problem with it stalling since wednesday. The car has a brand new coil, fairly new 7mm plug wires (6-8months, and going to upgrade to 8mm summit street/strip wires soon) and about 1month old bosh platinums. Ive read that people have had misfire problems with these plugs, and that they can cause pre-ignition in our cars (with stock heads), causing the knock sensor to retard timing causing a loss of power. so im switching back to copper ac delcos probably tommorow. I gapped them at 40 i believe, bc the stock gap is 35 and i read where the stock system can handle up to 45, so wih my upgraded ign system i bumped it up to 40. I dont think this is what caused my problems though.

The car just dies out of nowhere, i really have no clue why. It has the brand new coil, brand new esc, cap and rotor are fairly new (6-8 months), however, today i made an interesting find. I had the ign contole module tested 10+ times (it passed), and when i inspected the cap i found a gouge inside the cap along the wall. It was fairly deep, its obvious the stricker on the rotor was hitting it there. There was a black powder on the inside too, i was told that was from the rotor grinding away at the cap. I didnt replace the cap or rotor yet. I was told to check the distributor shaft for play, and it did have some but not a lot. I was told it should have some, so im not sure if its ok, or too much. The pickup coil will twist slightly and move up and down a little as well. This is the part i am most confused about.

Usually when it dies it will start right back up, however iv had several times recently that it took several times to restart, and ive noticed that sometimes when im trying to restart it after it dies and it wont start, the ses light will be off even when the key is in the on position, and sometimes it will flash and then go back off. Very strange, not sure what to make of this.

Im also getting a strange noise, seemingly from the drivers side valve cover area, i believe around cyl 1 & 2. I dont even really know how to describe it, its like a vibration noise almost...? It does corrospond with rpms.

So far, ive never gotten an ses light.

Could the platinum plugs make the knock sensor retard timing so much that it would stall??

Im very confused, and would appreciate all help. Thanks in advance

 

If your distributor shaft is loose enough to allow the rotor to contact the cap then it's time to replace it. I'd be willing to bet the noise you are hearing from the engine is coming from the distributor as well. I'd never advocate throwing parts at a problem, but in this case you have found something that is obviously worn well beyond its service limits and thus should be replaced before you can continue with troubleshooting.

 

When you say replace, you mean replace the distributor shaft right? I was told it could just be a bad bushing, is that possible?

If i go to the junkyard, i can use a distributor from a 3rd gen 305 right? Carbed, tpi, or tbi? Any other vehicles with a distributor i could use?

With the scratch in the dist. cap i figured that was probably enough evidence in itself that the shaft was the problem, but didnt want to jump to conclusions and start throwing parts at it, like you said. But is it safe to say thats the problem?

 

Honestly, for what a reman HEI costs, I would go ahead and pick up a whole dizzy so you get a new pickup coil as well. I think last time I checked at a chain store they were running way under $100, but if your budget is tight then you may as well pull yours apart first and see what all is damaged in there - it may well be salvageable.

I wouldn't say that this is definitely THE problem with your car, but I'm pretty sure it is A problem, and you won't really be able to accurately troubleshoot the rest as long as you've got a distributor shaft wobbling around.

EDIT: Just checked Advance Auto and remanufactured HEI is $99.95, brand new ones are $125-$130. As far as junkyard stuff goes, it's really a crapshoot but I think any HEI out of a computer controlled small block car (feedback carb, TBI, TPI) with the same number of wires in the connector (4? 5?) will work, but I'm not 100% positive. I believe your car is a roller cam motor, however, so you would want to keep the hardened drive gear off your current distributor if you got one out of a flat tappet motor at the 'yard.