I just bought a 1992 C4. I wanted to know if there was anyway to get a record of service from the dealerships. I am assuming they have some kind of network? The car was last on the road in 2015 and it looks like I will have a decent amount of investigation work to see what works and what needs to be repaired. I was hoping I would be able to get an idea of what work was done if it was done at a dealer of course.

Thank you for the help

 

First place I would go is the selling dealership and the dealership that maybe doing repairs if different, I worked as a Corvette mechanic in a very large Corvette Dealership in NJ in your time frame and every year when the cold file storage room would get tight we would Dumpster 10 year old or beyond requiered holding file, now in today's Digital world there might be hope for the newer cars. But those cars trapped in the 386 Computers or Pre-Pentium era which is what the Dispatcher used (Billing/Type of repair, Not actions or explaination of repair) and probably backed up on a Floppy maybe even a zip disk I'm afraid are lost most likely.

 

Spending time trying to track down what has been serviced may be a lesson in futility. Even Carfax may not be accurate due to some dealerships and repair facilities not reporting to Carfax.

Does the car run and drive currently? If so, just change all fluids including oil, transmission, differential, cooling, brakes, etc. as a starting point. If any codes are showing fix those issues. Then drive it making repairs as needed or make modifications that you would like to have on the car. Just keep doing regular maintenance and you should be fine.

 

I've found flushing the brake fluid in these c4s is critical. The ABS pump on these is sensitive and impossible to find a new one now. Old brake fluid gums up everything in these cars. The Master cylinder is also really expensive on this car.
As for your history, go to any chevy dealer. If its there they should be able to pull it up for you. They may require proof of ownership. Tell them you're thinking of bringing it in for a follow up service and want to see when it was last done so they don't think you're wasting their time.

 

You are absolutely right topfuel67!

"Brake Maintenance" is usually just replacing the pads but the Brake Fluid does need to be changed every five years or so. There are videos on YouTube showing how to do it. I bought a second ABS unit to have for spares and I hope I never need it. There was a great video posted by a Forum member about how to "break down" and "clean" the ABS unit. It was recent and was made out of the United States if I am correct.

I uses a Phoenix Reverse Bleeder and find the brakes fairly easy and quick after having done it a few times. The reverse bleeder pushes the fluid backwards UP towards the master cylinder. The 1988 C4 has a ONE Year only master cylinder and it has two lines coming out of it. One is for fluid OUT and the second for the fluid IN. I simply connect a small hose to the Fluid IN line and send the fluid to a clear gallon jug allowing me to see the difference in color of the brake fluid.

The 1988 has the fluid go to the ABS unit which then distributes the brake fluid. It goes to the front Right, front Left and the Rear brakes. The excess fluid in the ABS box goes back to the master cylinder. I ruptured a line stepping hard on the brake pedal and ALL the brake fluid ran out leaving NO brake working. Thank goodness I have a working Parking brake....

CARFAX was useless with my two Corvettes. The first was Too old and the second did not get entered into the system by the seller. I just know it came from New Jersey where it was purchased when new.

 

What was done in the past, so what.... Evaluate what you have and work from zero, pulling all maintenance (fluids/tune up) now that you are the owner. My 2c.

 

^^^ Learned the hard way that a seller for receipts, history is worthless if the wrench handler was a hack.
Same as anything in life happening prior to today really is insignificant.

Good advice above just start wtih the basics...things that can leak, are worn, look for funky wiring connectors. That little stuff can leave you stranded. Have fun with getting to know your new nemesis

Also x2 on the carfax thing. One driver I own doesnt show some bumps and bruises it got over the years even though they were reported.

Edit-If most of the work was done at the dealer...say new control arms at 70k its a safe bet the car was really taken care of. Most any dealership can enter your vin and pull it up depending on age

 

It was just worth a shot to ask. I have the FSM and I have to list of things to work on. It ran but on the way home all kinds of things started to fail. It wouldn't get over 4000 rpm, then 3000 ran and by the time I got home after a 85 mile drive I had only 1000 - 1200 rpm to work with.

The seller told me they put in a new fuel pump and filter, I have had the car up to confirm the fuel filter was new so I assume the pump was as well
New Opti - Looks like it has failed after 100 miles
New water pump - On closer inspection the water pump bolts have some shine on them that someone had them off recently, but the smaller bolts that hold on the fin'd cover are brown with age. I have my doubts on the new pump maybe just new seals, anyway that's getting replaced.
A refurbished ECM - they thought it just had an opti issue and then found the ECM worked when you hit it start a rough idle. It was done by Corvette Central so I hope that's a non-issue.
Bad AC programmer, the orange backlight no read out. I am going to send that to be refurbished. That should fix that issue.

What happened on the ride home,
Lost the turn signals - fixed cleaned off the haze on the fuse, started working again.
No horn - cleaning contacts started working again
Lost reverse - Big issue, when to back it out of the driveway, no reverse. I can get it into position and ZFdoc was kind enough to help me, almost sure its a blow weld on the reverse gear. $$$
Code 36 - the seller said they put in a new Opti - not sure what happened here.
Code 64 - Bad O2 sensors - replaced both code gone
I changed the oil, diff and trans fluid, it will get new coolant when I do the water pump.

Thank you for the suggestion on the brake fluid, it got new tires. It wasn't on the road since 2015 so they had dry rot etc.

Checked all the fuses in the passenger fuse box, no blown fuses, just the bad contact if you want to call it that.

I am going to replace the spark plugs, wires and serpentine belt while I have everything apart for the opti and water pump. I am going to check the injectors, see how that looks. After all that I hope I have a strong running engine and I can work on the transmission problem.

If all goes well I will have the car ready for the spring to enjoy it for a few years.

A got into this knowing it would be a project, we shall see how it goes and thank you all for the advice and help

 

If you have a fuel pressure gauge throw it on the shrader valve....pressurize it by turning the key to "on" the turn off and leave it for say an hour see how much it drops to what #

Most are long enough you can tape the gauge to your windshield and see the psi under load.
If all is good Id almost be suspicious of the cats being bad (if you have 0 codes). That can keep you from accelrating
Check your vacuum also. Sounds like youre capable of all this, most times problems are something simple

 

I am working on getting the AC programmer out to get fixed. Does anyone have an idea what this connector is for? It was jumped, and there is a plug close by with two black wires in it.

Thank you

 

If that yellow wire has a black 'tracer' I'd say the CSS (Clutch Safety Switch) has been 'jumper/bypassed' and the car should start without foot on clutch! The 2 blk wires go to switch up by pedal pivot!

8A-30-0 in the FSM.

 

Good to know, it could start in gear. I wonder what else I will find. Thank you telling me what it is.

 

CTmccloskey, the two lines on the master cylinder on the 1988 Corvette are both output lines going to the ABS. The ABS has two input ports, one for the front brakes and one for the rear brakes, and three output ports, two for the front, a right and a left, and the last one for the rear, which services both the right and left rear calipers. I have no idea where you got the idea that the two ports on the master cylinder are an in and out.

 

Interesting day working upside down and sideways. Got the A/C programmer off, I was expecting to find things in OK condition. Just thinking the capacitors would need to be replaced due to age. This little surprise was waiting for me, a corroded off pin and a mess in the connector. Is this just an unfortunate circumstance of age? Or is this something else at play that caused this? There was no visible water damage on the card board backer or in the connection or box itself. Just in the connector. The pin that corroded off of course was stuck in the connector. It is the orange wire which I believe it the defroster? 4th pin in starting at the right, on the row that the connector lock latches over the plug. I got it out, time for a drink.

 

Orange C4 in that connector is 'Battery Input'. The terminals are Metri-Pack 100 Female and should be a relative easy find. Delphi (Aptiv) would be I believe a 12146447. If you've an older GM dealer in your area they might likely still have. A parts guy or service technician familiar with electrical might know where the terminal inventory is. Should be in 'Drawer 3' if they can help you.

 

^^^this dude is an encyclopedia when it comes to these cars
That clutch switch is just one more thing that can leave you stranded keep it bypassed

 

All the help is much appreciated. The well of knowledge here runs deep and I am sure I could use the help.

Question are the mineral oil smoke generators a good tool for vacuum line diagnoses? I see you can make one for less then $30 bucks and visually I can see lines that look suspect. My plan was to use a vacuum line tester to start and the smoke if the vacuum testing shows me issues and I can't locate them.

 

Question for the group. Is there a story to be discovered here? The paperclip is the front of the motor.

 

I have one and it is priceless when it comes to finding vacuum leaks.
If you are a DIY mechanic then it will be money well spent.

 

Looks a little rich but nothing horrible.

As far as the smoke machine, I made one with a mini compressor, a mason jar, some resistor wire I had laying around (it was a thick type used for smoke effect/vaporizers) baby oil and an old cotton rag. Hooked up to a car battery for a few seconds with the soaked rag it would start a smolder and smoke for about 5 minutes then unplug after that occurred. The regulator was turned down to it barely had flow and that was that. Worked well for what I needed, almost too much smoke but very thick so you would see it. It is a great tool to have imo. I actually only needed it for an intake leak and coincidentally found several other issues along the way. So technically it sucked because I had to fix more than I thought lol.