My Hyundai Sonata V6 restoration reaches the final stages of completion

The car was taken on its first drive to the local Hyundai service center for wheel alignment and balancing.

BHPian ads295 recently shared this with other enthusiasts:

Hello all!

We're in the final stages of completion.

The big cat is fully assembled and mechanically OK. Since the steering was opened up to replace the axle oil seal on the front, and the joints were fully removed to clean up and grease, and also since the car has all new tyres, the car was due for a steering alignment and balancing ASAP.

Electrically though, there are some issues that we're facing.

• The airbag light stays on and doesn't go away even after starting the car.
• Only 1 speaker of 4 works.
• The radio head unit plays cassettes but doesn't play CDs - it ejects them after attempting to play. The antenna doesn't extend on activating the radio even though the motor itself was tested to be working perfectly in isolation.
• The dash doesn't show the transmission level position (P-R-N-D). The gear indicator briefly flashes "4" sometimes as if it were in 4th gear, even when parked in P. Click/tap the below image to view the GIF.

Thus the cat was taken on its first prowl to the local Hyundai service center for wheel alignment and balancing. It was my mechanic who was behind the wheel, though, and he said the car runs well. He noted that the gearbox seemed to be shifting just a little smoother than earlier. Once the fresh oil cycles properly through all the gears, I expect this to improve even further (remember, we've still only flushed maybe half the system). For posterity's sake, I insisted he get an OBD scan done there, since my cheap ELM327 BT scanner didn't work (couldn't connect to the ECU).

We got many codes, some of which raised more questions than they answered. First let me share the codes themselves, below:

Some notes from the codes:

• The airbag light is on but there are no codes for that. Strange
• There are 2 distinct definitions for the same code, C1256. There's no height sensor on my car so I assume the other one is relevant to me.
• The wheel speed sensor on the Rear Right is suspect - either a loose connection or a malfunctioning sensor.
• There is no auto headlamp levelling system on my car from the factory, so we'll be ignoring that code.

We'll check out the wiring for loose connections in the relevant areas e.g. the TCM error and the dash issues are surely related, probably due to a loose connection or rusty contacts (I should've handed my mechanic a can or two of contact cleaner when he was putting the wiring back together, in hindsight).

We're fixing the low-lying fruit first, namely the wheel speed sensor, the brake switch wiring, and the TCM to ECU wiring. Fingers crossed that solves all of the codes.

If anyone has specific, knowledgeable inputs (from experience) to share about the root cause of my errors and problems, please feel free to chime in!

I contacted tBHPian "1self" for tips, too.

Large cache of spares from the scrap dealer

After paying the first advance on 7th of August, I finally got the entire order of spares I actually paid for, today, on the 23rd of October. It was a lot of work following up, a lot of anxiety, and an inconsiderable amount of risk. I'm so relieved this chapter is closed!

So what all did I get? Front passenger side airbag, wooden centre console with AC controls, side AC vents, fuel pump, interior door handles, front driver side power window switch assembly/armrest, windshield wiper motor + arm assembly, interior cabin light, transmission control unit (TCU), ABS module, the complete cooling coil assembly with blower motor, the mass air flow (MAF) sensor, and lastly the radiator + condenser assembly. The condenser isn't in very good condition (fins are peeling off in places) but I've been assured it's leak-free, which I will test for.

Why did I take such risks for backup parts when there's little obviously wrong with the car?

• While the car has a rep for being reliable, it's still nearly 20 years old. It's hard enough to find a Sonata coming in for scrap parts, let alone a V6 (which I found here.)
• I was able to secure top-quality parts for rock-bottom prices - I paid a princely sum of ₹27k for all the above parts PLUS the parts I put up a few posts ago. Compare this with the cost of purchasing a single MAF sensor brand new - ₹17k approx, that too excluding shipping from Korea. Win!

The guy still played it smart and didn't send the gear shifter assembly and airbox that I'd asked for, but I'd negotiated and left ₹5k as balance to be paid only after delivery, so I'll pay him only after receiving those parts (meaning I've only paid ₹22k so far).

Found timing belts on the cheap from Boodmo

The OE timing belt, manufactured by Gates, cost me a steep ₹6,873 through Mobis India. I myself was surprised it cost so much, but wanted to use OE only. I was randomly browsing Boodmo when I found they had ContiTech timing belts for the V6 EF-B Sonata selling for ₹400 apiece, with an MRP of ₹2,300 approx! I even checked Conti's catalogue and double-checked - the CT1085 belt is indeed made for my car. I was shocked beyond measure and asked my mechanic if it was worth buying. He stated the obvious, that replacement internals are 60k miles, so the car is good for now. I didn't buy them.

Two days later I'm checking Boodmo and the belts (2pcs in stock) are now on sale at a 90% discount, for ₹200 each! I just couldn't miss the deal and bought two ContiTech CT1085 timing belts for a princely sum of ₹406 including shipping.

The way forward

As it stands today, the car is good to go, but I'm keen on sorting out every last issue before I take her home. A quick list of what's yet to be done:

• All the electrical gremlins mentioned above
• Sorting out the relevant OBD codes
• Headlight buffing + clear coat application
• Coolant flush + new radiator inlet and outlet elbows to be fitted
• AC system leak check + gas recharge

I've lost count of the number of family occasions I wanted this car to be part of, but have been missed - my own birthday, my wife's birthday, her sister's engagement, and finally, the arrival of my first child 3 days ago, on 21/10/'24... But there's a different kind of satisfaction with a job well done.

Until next time!

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