r/c4corvette

1984 Automatic with 82k miles. Literally zero rust. Sat in a garage for years, as is the case for many of these cars, and I’m gonna give it the life it deserves.

I recently was got my c4 corvette working and I’m trying to get some cold air from the ac. I’m not the original owner and I have no idea if this car uses r12 or r134a. I’m pretty sure it’s still on the r12 system but I just wanted to be sure so I’m asking for help. Does this look like r12

I can't imagine how many thousands of dollars I have spent in my life on OEM European hydraulic motor mounts over the years, because I learned very early in my automotive hobby journey that aftermarket rubber parts suck ass by and large. Yet for some reason my optimistic self figured hey, it's just an old 350 chevy, surely the aftermarket mounts are fine. Well no tf they were not. Not only were they butter soft, but they didn't begin to line up correctly out of the box and were an astounding pita to install. Unfortunately GM no longer makes them but I was over some time able to rummage up a couple of NOS ones on ebay. They weren't even expensive. They slid right in with minimal fuss and are worlds stiffer. That one on the right has maybe 2k miles on it and the insert is literally flopping around in the housing it's so deformed already. They were soft enough I had a clutch shudder till I replaced the driver side with OEM a few months ago, finally getting around to doing the pass side now. The hell of it is I doubt my originals at 160K needed replacing, they weren't oil soaked, I was getting desperate trying to find a weird vibration (it wasn't the mounts) so I could have left well enough alone.

I still have a slow pressure leak (89). Primes to 42psi, stops at 38, and drops slowly before ignition is on.

I tried the technique of clamping send / return lines to isolate where the leak is coming from, but no configuration of clamps held the pressure. I believe if pressure holds when you clamp the send line, the pump is bad. If pressure holds when you clamp the return line, the regulator is bad. And if you clamp both lines and still have a leak, then an injector is leaking.

Well, no matter what we clamped, it leaked. I have already installed a new fuel pump and fuel pressure regulator, and my injectors show health Ohm resistance (though I know this means that they can still be leaking).

Video is us crimping the send line, and as you can see when we un-crimp it the pressure plummets. Same outcome if the return line is crimped in addition to the send line.

I tried to delete my fuel pulsator incase it was shot but it didn’t change anything. Please help

So I have a 1985 corvette, runs perfect, fresh oil change, plugs, cap, rotor, IAC valve, runs like a top. I’m having a check engine light come on, but only when I’m using cruise control for at least 5-10 minutes. Have no idea what it could be. Every vacuum line I can get my eyes on seems fine, nothing broken, or leaking (as far as the eyes can see) anyone else have this issue or know what could be causing it? The cruise control still works perfectly fine the entire time too.

Original Price 7500 seller saying they’ll do 6, thoughts? 123k Miles

Just did brakes all around and cleaned up the wheels whilst waiting on parts that were initially defective. Had an artistic friend help with the letters… I’m wicked stoked after all that tedious workmanship.

EDIT

Discovered the problem! It's the harmonic balancer. The weight has slipped off the hub because the rubber ring broke. Someone in the comments noticed the movement in the video. Thank you all for the help!!

Does anyone have any ideas what this sound might be? Never had this before. Doesn't sound like engine knock to me as it's too slow and clunky sounding compared to what I've heard before in other engines.

I took my 1985 corvette to a shop to get its engine rebuilt because of a tick the car had. Ever since I got it back the car has never ran quite right with me having to hold the gas to keep the car on and having a small backfire from the exhaust on top of other major problems with the shop that did the rebuild. I’m not sure if I want to go ahead and take out the engine and build it myself or scrap the L98 and go full send with a LS1 build has anyone built the L98 and made reliable power at 500Hp With EFI? And is it worth it compared to the LS swap?

Im sure its a c4 motor, just dont know which one. Engine swap on 1970s c10

I've always been into 90's and 00's Japanese cars for as long as I can remember, but every time I'd take my dog out, we would walk past this body shop and stare at this C4 just sitting abandon in their back lot. Couple years went by and I decided to do some digging and found out where the owner lived. I walked over to his house and offered to buy his car. After a little hesitation, we agreed on $2,800 and the car was mine.

Mechanically, the car is solid. It runs and drives. Interior is in great shape too. The instrument cluster doesn't work and the car definitely needs a paint job. Aside from that, the car is a blast to drive and I have a new found appreciation for old American cars. Feels good to be a part of the C4 club. Can't wait to restore this car to its former glory.

First time cranking since getting into an accident a couple months ago. Charged the battery and cranked right up.

It wasn’t making this sound before the accident. Curious if anyone knows what this sound could be?

$4k for a 6-speed manual LT1 with only 68k miles, I think that's a good deal

When I got it, I sort of assumed it'd be a bit boring. I mean it has as much hp as my daily while not being that much lighter. But holy crap this thing is fun to drive.

it wasn't running when we got it because of a recent electrical issue the owner had. But with the help of my friend's unpaid labor, we got it started in just 3 days.

So far I'm loving this car, any tips for a first time c4 owner?

To preface, I’m still kind of new to cars and am learning as I go. So, I turn it on, the engine starts, begins to rumble and stutter, I put it into gear, then the engine shuts off.

EDIT: Replaced IAC, starts up and runs when gas is pushed to high revs, but revs will slowly lower until the engine shuts off again

My understanding is that the only difference between the 84-85 door insert and the 86-89 door insert is the power locks button area. I am modeling based on an 85 and would like to create a modified version for 86-89. I am looking for two things.

1. A clear picture of the backside of the 86-89 door panel insert so I can get measurements.

2. Someone that can test print and confirm fit of the 86-89 panel (as a thank you I can send you the files for any of my parts that you may be interested in for free).

Sucks but it had to be done

Fiberglass repair on the front body kit. Upside down lying on the driveway to get underneath was awful with resin dripping. But like the title says, it had to be done. A lot of the lower lip was hanging on with bondo, silicone, and hopes and dreams. Previous owner was obviously rough on some curbs with this car so low.

Next up sand and smooth it with some fiberglass filler. Then get this cup car splitter mounted. NASCAR used a material called tegris, which is like a plastic version of carbon fiber. It’s super tough and will be a sort of sacrificial scrape plate as well as provide downforce for this mega horsepower stock L98 lol.

After that, the rest of this body kit needs adjusting then flashy paint at some point.