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Monday 9am - 5:30pm Tuesday 9am - 5:30pm Wednesday 9am - 5:30pm Thursday 9am - 5:30pm Friday 9am - 5:30pm

Nelson Performance

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San Antonio, TX
Nelson Performance

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GM LS & LT Performance, Diagnostics & Tuning LSx Performance Specialists
Trucks/cars/suv
GO FAST! In house dyno, tuning, custom wiring, installation, parts.

HPTUNERSD - FAST XFi - Holley EFI

Please contact Nelson performance at 210-626-0278 or at [email protected] for any orders or detailed pricing questions/ inquiries.

10/26/2026

This 2008 Chevrolet Corvette C6 rolled into Nelson Performance for a MAJOR power upgrade, and we're turning up the heat! 🏁💪

That 6.2L LS3 is getting a serious dose of performance with some upgrades designed to take this Vette to a whole new level! 🚀

🔴 A&A Supercharger System – Bringing BOOST into the equation! More airflow, more horsepower, and a whole lot more excitement behind the wheel! 💨

🔴 Performance Headers – Helping that LS3 breathe easier, improve exhaust flow, and unleash that unmistakable V8 sound! 🔥

🔴 Custom Tuning – Dialing everything in to bring the combination together for strong, reliable street performance! 💻⚡

💥 NATURALLY ASPIRATED WAS FUN… BUT BOOST IS BETTER! 💥

The C6 Corvette is already an incredible performance platform, but adding forced induction takes things to another level. We're talking serious power potential without sacrificing the street manners that make these cars so much fun to drive!

And let's be honest… there's just something about a BOOSTED LS3! 😎🔥

🏁 NELSON PERFORMANCE
📍 San Antonio, Texas
🔧 TUNING. DIAGNOSTICS. RESULTS.

10/21/2026

🔥 **2014 Silverado 5.3L — IN FOR A CUSTOM TUNE!** 🔥

This clean black Silverado stopped by Nelson Performance for a little fine-tuning! 💪

A custom tune isn't just about making more horsepower. It's about getting the most out of your truck and improving how it performs every time you get behind the wheel.

🔴 **What can a custom tune improve?**

✅ **Throttle Response** – Sharper, more responsive acceleration.

✅ **Horsepower & Torque** – Optimize engine performance and unlock additional power.

✅ **Transmission Performance** – Adjust shift points, shift firmness, and overall drivability.

✅ **Fuel Economy** – Improved efficiency is possible depending on driving habits and vehicle condition.

✅ **Overall Drivability** – Smoother, more consistent performance tailored to your truck.

At Nelson Performance, we don't believe in one-size-fits-all tuning. Every vehicle is different, and our custom street tunes are calibrated around your specific setup, fuel, and performance goals.

Whether your truck is completely stock or has a few upgrades, the right tune can make a noticeable difference!

📍 **Nelson Performance | San Antonio, TX**

📧 [email protected]

**TUNING. DIAGNOSTICS. RESULTS.**

10/19/2026

🔥 **2021 CHEVROLET TAHOE Z71 – ENGINE & TRANSMISSION TUNING!** 🔥

This sharp red Tahoe Z71 is in the shop for a custom engine and transmission tune, along with two changes the owner will definitely appreciate — **DFM and Auto Start/Stop disabled!** 💪

Modern GM vehicles come with factory programming designed to balance performance, fuel economy, and emissions requirements. But not every driver wants the factory driving experience!

Here's what we're addressing on this Tahoe:

🔴 **DFM (Dynamic Fuel Management) Disable**
DFM allows the engine to deactivate cylinders under certain driving conditions to conserve fuel. By disabling this function through the ECM calibration, the engine will operate on all eight cylinders instead of constantly switching cylinder activation modes.

🔴 **Auto Start/Stop Disable**
No more engine automatically shutting off at stoplights and restarting when you release the brake. Just a more consistent driving experience without the repeated shutdowns and restarts.

🔴 **Custom Engine Tuning**
We're optimizing throttle response, power delivery, and overall engine performance. The goal is a more responsive Tahoe that delivers smooth, consistent power when you need it.

🔴 **Custom Transmission Tuning**
Engine tuning is only half the equation! We're refining shift points, shift behavior, and torque management to improve responsiveness and deliver a more enjoyable driving experience.

💥 **THE END RESULT?**
A Tahoe that responds better to driver input, shifts more confidently, and delivers the performance and drivability the owner is looking for.

At **Nelson Performance**, our calibrations aren't one-size-fits-all. We tailor our tuning to each vehicle, its modifications, and the customer's driving preferences.

📩 Interested in custom tuning for your GM truck or SUV? Email **[email protected]** with your year, make, model, engine size, and what you'd like to accomplish!

**NELSON PERFORMANCE**
TUNING. DIAGNOSTICS. RESULTS.

10/18/2026

🔧 **TECH TIP SUNDAY!** 🔧

🚨 **A MISFIRE DOESN'T ALWAYS MEAN A BAD LIFTER!**

Your engine starts running rough, hesitating, or misfiring, and suddenly you're worried about one of the most expensive repairs on your GM engine. 😳💸

But here's something you should know!

⛽ A failing fuel injector can cause symptoms that feel very similar to a mechanical engine problem.

A faulty injector may:
🔴 Deliver too much or too little fuel
🔴 Cause intermittent misfires
🔴 Create hesitation or loss of power
🔴 Cause rough running under certain driving conditions

And here's the tricky part: **An injector can malfunction intermittently, making the problem harder to pinpoint.**

That's why proper diagnostics matter!

At Nelson Performance, we don't automatically assume a misfire means lifter failure. We test the fuel, ignition, electrical, and mechanical systems as needed to identify what's actually causing the problem.

💡 **Today's takeaway:** A misfire is a symptom, not a diagnosis!

🔧 **NELSON PERFORMANCE**
Tuning. Diagnostics. Results.

10/17/2026

🚨😴 CAUGHT SLEEPING ON THE JOB!

JUST KIDDING! 🤣🔧

This C10 is getting a **complete chassis rewire**, and that means getting into some pretty interesting positions!

We're replacing the old wiring harness along with those crusty, aging electrical connectors, terminals, sockets, and pigtails. Years of heat, corrosion, and wear can take a toll on electrical connections, so we're making sure the new wiring has reliable connections throughout.

It's tedious work, but doing it right matters! 💪

Who needs yoga when you work on classic trucks? 🧘‍♂️😂

🏁 Nelson Performance
Tuning. Diagnostics. Results.

10/16/2026

🚨 **ALL THE WAY FROM EAGLE PASS, TX!** 🚨

**Multiple shops. A dealership. Still misfiring!** 😳🔧

This 2019 Chevy Tahoe made the trip from Eagle Pass to Nelson Performance after several unsuccessful attempts to get to the bottom of an intermittent misfire.

Here's what we were working with! 👇

🔴 The dealership suspected the fuel pumps.
🔴 Coils and spark plugs had already been replaced.
🔴 The misfire continued, primarily during highway driving.
🔴 The customer feared he might have a failing lifter. 💸

**ENTER RAY!** 💪🔍

In LESS THAN ONE HOUR, Ray narrowed the problem down to **TWO faulty fuel injectors!**

✅ Fuel pressure checked out GOOD!
✅ No evidence of lifter failure!
✅ Two problem injectors identified!

We recommended replacing all the injectors and associated harnesses. Unfortunately, our customer couldn't stay for the repairs, but he left with something he hadn't gotten elsewhere — **ANSWERS!** 🙌

💰 And those answers could save him THOUSANDS in unnecessary repairs!

❤️ To our customer from Eagle Pass, THANK YOU for making the drive and trusting our team!

🏁 **STOP GUESSING. START DIAGNOSING.**

📍 Nelson Performance | San Antonio, TX

**TUNING. DIAGNOSTICS. RESULTS.**

10/15/2026

🔥 **2003 GMC SIERRA — NOT EVERY FIX NEEDS A REPAIR BILL!** 🔥

This beautiful Sierra is no stranger to Nelson Performance! 😎💪

We've had the pleasure of working on this truck before, including a full custom tune, fuel injectors, fuel pump, and O2 sensors.

When a customer continues to trust us with their vehicle, that means something to us. We appreciate that loyalty, and we don't take it for granted! ❤️

🔧 **SO WHAT BROUGHT HIM BACK?**

The customer wanted an idle adjustment and thought the truck needed a retune.

Allen hooked up the laptop to take a look, and guess what we found? 👀

🌡️ **The engine temperature sensor was UNPLUGGED!**

Here's why that matters! 👇

The engine computer relies on temperature readings to determine how much fuel the engine needs and how to manage certain operating conditions. When that information is missing, it can affect how the engine runs, including idle quality.

✅ Sensor reconnected.
✅ Issue identified.
✅ No retune necessary.
✅ **NO CHARGE!** 💯

We could have charged for a tuning adjustment, but the truck didn't need one.

**THAT'S THE DIFFERENCE BETWEEN SELLING A SERVICE AND SOLVING A PROBLEM!** 🔥

At Nelson Performance, we're not here to sell you something your vehicle doesn't need. We're here to figure out what's actually wrong and get it right.

Sometimes it's a major repair. Sometimes it's a simple connection. Either way, you deserve an honest answer.

🤝 To our returning customer, thank you for continuing to trust us with your Sierra. We appreciate your business!

🏁 **NELSON PERFORMANCE**
*Tuning. Diagnostics. Results.*

10/12/2026

🚨 **NO START! AND THIS ONE HAD A TWIST!** 💀🔧

Sometimes the biggest problems start with the smallest shortcuts! 👀

This 2017 GM engine came to Nelson Performance with a **NO-START condition.** During diagnostics, we discovered there was NO fuel pressure coming from the high-pressure fuel pump.

Time to investigate! 🔍

Our inspection uncovered something interesting...

The customer had installed a fuel pump that wasn't correct for this engine. The electrical connectors weren't compatible, so instead of using the correct pump, they decided to **JUMP THE CONNECTIONS WITH WIRES!** 😳⚡

Take a close look at that picture. YES, those wires are connecting two plugs that were never designed to work together!

🚫 **HERE'S THE PROBLEM!**

Just because you can make an electrical connection doesn't mean the components are compatible!

Modern GM direct-injection fuel systems are precisely engineered. The high-pressure fuel pump must be compatible with the engine's fuel system and control strategy.

A couple of jumper wires won't magically make the wrong pump work!

⚠️ Incorrect components and improvised wiring can lead to:
🔴 No-start conditions
🔴 Fuel pressure and control issues
🔴 Electrical faults
🔴 Potential damage to expensive components
🔴 More money spent diagnosing and correcting the original mistake

💡 **THE TAKEAWAY?**

**THE RIGHT PART MATTERS JUST AS MUCH AS THE RIGHT INSTALLATION!**

Saving a few dollars or trying to make an incompatible part work can turn into a much more expensive repair.

At Nelson Performance, we don't just throw parts at a problem. We investigate, test, and find out WHY something isn't working.

👀 **BEFORE YOU READ THE CAPTION, DID YOU SPOT THOSE JUMPER WIRES?**

Drop a 🔧 if you caught it!

**NELSON PERFORMANCE**
TUNING. DIAGNOSTICS. RESULTS.

10/11/2026

🔧🎃 **TECH TIP SUNDAY!** 🎃🔧

🩸 **YOUR ENGINE IS THIRSTY… AND YOU MIGHT NOT EVEN KNOW IT!**

🚨 Just because your truck isn't leaking oil doesn't mean it isn't LOSING oil!

Did you know some GM engines can burn oil between oil changes without leaving a single drop on your driveway? 😳

By the time you notice, damage may already be happening!

🔍 **WHERE IS YOUR OIL GOING?**

🔴 **AFM/DOD Systems:** Certain GM engines equipped with Active Fuel Management have known oil consumption concerns.

🔴 **Piston Rings:** Worn or stuck rings can allow oil into the combustion chamber, where it burns with the fuel.

🔴 **PCV System:** A malfunctioning ventilation system can pull excessive oil into the intake.

🔴 **Valve Stem Seals:** Worn seals can allow oil into the cylinders, sometimes causing blue smoke at startup.

💀 **HERE'S WHERE IT GETS SCARY!**

Running low on oil can cause:

⚠️ Camshaft and lifter damage
⚠️ Timing chain and valvetrain wear
⚠️ Bearing damage
⚠️ Complete engine failure 💸

🚨 **DID YOU KNOW?**

Your oil pressure gauge is NOT an oil level gauge!

Your engine can be dangerously low on oil and still show oil pressure.

🛠️ **HOW DO YOU PROTECT YOUR ENGINE?**

✅ Check your oil regularly between changes.
✅ Monitor how much oil you're

10/10/2026

🏁 **MONDAY'S BUILD. FRIDAY'S HEAD START!** 🔥

This 2008 Corvette wasn't scheduled to start until Monday… but it's Friday, the car is here, and our guys aren't wasting any time! 💪🔧

We're getting a jump on the teardown so we can get this Corvette ready for its next chapter!

👀 **Now take a GOOD look at that parts cart!**

What do YOU think we're getting ready to install? 🤔

We're not spilling the details just yet! 😎

We'll be taking you along throughout the build — from teardown to installation, tuning, and the finished product.

🔥 **FOLLOW ALONG for progress reports and the big reveal!**

👇 Drop your guesses in the comments. Let's see who knows their Corvette upgrades!

Address

10034 Roosevelt Avenue
San Antonio, TX
78214

Opening Hours

Monday	9am - 5:30pm
Tuesday	9am - 5:30pm
Wednesday	9am - 5:30pm
Thursday	9am - 5:30pm
Friday	9am - 5:30pm

Telephone

+12106260278

Website

http://www.nelsonperformance.com/

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