Hi, I have recently picked up a 1993 Chevy Caviler Z24 for about 500 dollars. A project car, of sorts. Overall, there is not too much rust on it, considering I'm from Upper Michigan where there is lots of snow and salt. There is some frame rust, but it is a uni-body frame so it shouldn't be heat treated, I can just welt a piece of sheet still in the rust spot.
The issue I am having is there is a misfire making the car shake like a dog in a storm. To be honest, I'm not sure which 2 cylinders are misfiring. I am very sure that it is an issue with one of the coil packs. I used a spark tester and two of the spark plugs were firing almost exclusively at higher RPMs. I have been told that these coil packs are known for going bad in these types of cars, so I intend on replacing all 3 coil packs. However, it is EXTREMELY
difficult to get to them. I cannot for the life of me fit my hands down into the car to get to the coil packs. I had only managed to get the middle pack replaced, the rest I had no luck with. It looks like I'd almost have to pull the entire radiator out from the bottom of the car to get to these darn coil packs. Does anybody have any idea of a better way to get to these packs?
I'm really hoping the misfire isn't due to some issue like stuck or blown piston rings, as that would be a whole other can of worms. I'm just trying to start with the easy issues first. Truth be told, I don't know how many miles the car truly has, as the Odometer is stuck at 40,000 miles. I guess that means it only has 40,000 miles
I would appreciate some help
When I replace coils, I remove the entire unit. I'll also re-paste the ICM while its out. For me, it is easier to remove the unit than to try to replace just the coils with it still mounted to the engine.
I apologize for the late response, life got in the way. The issue I'm having is there is little to no clearance to get to the ignition coils. Do I just go in blind and try to do it? The coils are below the exhaust manifold, and I have thought about removing the coolant fan to give me more clearance, but it's really tough, I'm avoiding taking everything apart if possible. But if need be I'm willing to. Thanks!
I jack up the front of the car a few inches and put jack stands under it. Then remove the air dam, quick to do and offers more room to work. With a swivel head and extensions the 3 bolts that hold the coil pack to the engine are accessible. I don't think I took the radiator fan out, but I don't really remember. You can first try it from underneath and see if you can get to the bolts, I think you can. If not, well then I guess you can remove the fan. It will give you more room for sure. I don't think it is necessary though.
Good luck and be sure to use thermal paste on the heat sink (the metal plate the ICM mounts to). Super Lube White Grease IS thermal paste. A 3-Oz tube is very inexpensive.
This is a bit old and you may have already figured this out but my experience may help others.
On my '92 Sunbird with 3.1, with the starter removed, the coils are easy peasy to get to. The 1st/2nd time I changed them I did from the top, could just get my hand down between the rad & engine. I'm now just finishing up a rebuild of the engine due to all the gaskets failing after 30 years, lol, and found with the starter out, the coils are right there and easily accessible.