My tach is jumping 200-300 randomly. Always under load, never at idle. Tends to happen more when it's hot. Sometimes you can feel the car hesitate for a split second, but not often enough to be consistent. Search turned up the idea that the wires going to the coil were going back, but mine look perfect. Brand new coil, as well. Tracing the cables the other direction leads me to the ignition module. Could it perhaps be the culprit?

 

It's very possible.

 

could be that, sensor problem (mine was the tps - check to make sure its at .54v? or .55v? at idle. i can't remember), the distributor, or even your plugs / plug wires. single out the culprit

 

+1 for plug wires
my car did the same thing i replaced the ign moudle and pickup in the dizzy didnt fix it
threw on a set of p[lug wires and it went away.,though my tach jumped around like 800-1000 rpms

 

The plug wires arne't that old and appear to be perfectly fine. Haven't checked the plugs yet. Coil is new, connecting wires look fine. I've had another vote for ignition module(the problem sounds similar to a car dying when it's hot and not starting until it's cool and how the ignition module is the problem). I've also got an offer for a dizzy from a 4th gen Camaro with low miles for $20. I'll check the plug wires again, and I found out the ignition module is only $35. A "new" dizzy would be good to replace my 200k one too, I'm sure.

 

replace the distributor cap and rotor, i had the same problem. fuel might be a problem, fuel filter might need to be replaced. possibly injectors need to be cleaned

 

The car is getting fuel, never stumbles hard enough to indicate it's not. A very very slight hesitation is the only thing aside from what would appear to be an electrical issue, and even then, it's inconsistent. I'm fairly certain at this point that it's an ignition issue.

 

my wires also looked fine,no burn marks or arc marks but sure enough it fixed my problem

 

I don't think the 4th gens came with a dizzy...ever on a v6. IIRC, they started using the 3.4L in the 4th gens (93) and they were all DIS. I can't ever recall seeing one with a dizzy.

 

It would have been a v8, then. I wasn't told the exact year, but the guy is a Camaro freak like ourselves() and tends to hoard old parts. The vast majority of them are 4th gen. I'm still waiting for him to tell me which of his Camaros it came out of. A search on PartsAmerica.com for a dizzy for my car and any random 4th gen car yields the same AC Delco part number, so it should work fine.

 

mine did the same. i had to get the wires that went to the tps fixed. that did the trick btw i have a 2.8

 

Turns out it was crappy wires. The metal contacts inside had come apart from the wires and instead of sparking onto the plugs, they were just concentrating a spark in that direction. The heat and vibration made it worse.

I found this out while on a road trip and had to replace them on the side of the road. I had attempted to replace a distributor with a new one before the trip, but the new one was defective, so I put my old one back in... due to bad wires, the dizzy was one tooth off. The new wires resulted in the engine not firing. The old dizzy's cap housing had broken away from the shaft and made it impossible to set the spark advance, so I ended up having to replace a distrubutor, set the base timing and spark advance... all on the side of I-65 outside Louisville. What a weekend. -_-