1991 abs part seach, volts issue, bogging down

[POLOG91]

Hello. I've had my 1991 L98 convertible since it was new. It currently has 44,575 miles on it. Last month, the ABS light came on & the dealer I am now going to couldn't pull any codes with the paperclip method (they didn't have the adapter for the diagnostic). They sent me on my way while we tried to locate an adapter. We did flush transmission, brake & power steering system and they found a loose spark plug. In the meantime, I see that the volts gauge is fluctuating sometimes in idle (parked or stopped at light) & when I shut the car down the gauge goes below the marked area. The alternator & battery checked out fine but after checking them the light went out! I assume it was something we touched - a loose connection - that didn't allow enough power for the ABS system to self check on start up?

Well, 8 days ago I start up & the ABS light is on again. Shortly into my drive, I sense it isn't shifting right. Trying to get to 40MPH the RPM's are above 2000 & it's taking too long to make that shift. It wasn't every time. The volts were erratic at stops or if I let it coast. About 30 minutes into my drive, it really started having trouble ... trying to get above 28mph it was straining, the RPM's were over 2000 & the car was rumbling/vibrating. Once it got past that, it ran at 55MPH fine. I was on a highway felt I had no choice. I hit maybe 4 lights & this happened each time. I tried to accelerate slowly for fear of causing damage.

So, back to the dealer. Now they have found the diagnostic adapter & get a code 63 for the ABS solenoid valve relay - pressure, part #14105967. Of course, that part has long been discontinued & they have tasked me with finding an LKQ or salvage part.

I hope someone can help me locate this part. Also, I am looking for thoughts on the volts issue & the car bogging down which the dealer is still trying to figure out. Could this all be related? Here's some more history ......

In the past 3k miles there has been some major work ... It ran beautifully until 1/08 (41k) when I was told the head was leaking. So, the shop (not the dealer) had the top of the engine redone ... R&R top of motor - replace lifters - head gasket - pcv valve - new alternator. In 8/09 I was experiencing rough idle at stops which quickly turned to it wouldn't accelerate ... major vibration. Went to my mechanic & was told the system was full of sludge & deposits. They said it was due to a bad coolant temp sensor. The work done was a 'major tune up plus' consisting of new injectors, sparks, wires distributor, ignition module, coil, coolant temp sensor and they cleaned the egr valve, throttle body, etc. They said they cleaned everything they could except the fuel tank. Ever since I got it back, I noted a slightly rough idle on a cold start. It only lasts until I pull onto the road, but it never did that before. Of course, that mechanic says it's normal or he doesn't sense it

Sorry for the book, but I see too many posts on the Vette sites where folks come back with questions as to what work the car has had.

I really appreciate any help that can be offered with diagnosis & the PART! Many thanks.

[POLOG91]

I have an update. I found the part! Rock Auto has this relay, 14105967. I got it with 1 day mail service for $68. The interesting thing is that while it came from a company called Airtex/Wells, the part had Bosch on it. So the ABS works now. I am waiting still on the bogging down issue. Right now they are looking at the fuel pump & a damper.