Why does my Pontiac Sunfire start and then die?

Short answer: If a Sunfire starts for a second or two and dies, the Passlock anti-theft system is usually shutting off the fuel because it didn't get the right signal from the ignition lock cylinder. A weak battery or a worn ignition switch can cause that. Check the battery first, read the codes (theft codes like P1626 and P1632 confirm it), and check your VIN for the ignition switch recall.

Symptom: Most of the time it starts and drives fine. Sometimes it fires for 1–2 seconds and shuts off, or cranks without starting. The security light may come on or flash.

What to check first

1. Test the battery and clean the cables. A battery reading around 11.3 volts is effectively dead and can confuse the anti-theft system.
2. Read the codes. P1626 and P1632 are theft-deterrent codes that point to Passlock shutting off fuel.
3. Watch the security light during a no-start.
4. With the key on during a no-start, check other accessories (fan, wipers, radio). If some are dead, the ignition switch is suspect.
5. Check your VIN for the ignition switch recall at nhtsa.gov/recalls.
6. If it cranks without starting at all, check for spark with an inline tester and look at the spark plugs.

Likely causes

1. Passlock anti-theft system shutting off fuel. The system cuts the fuel pump and injectors if it doesn't see the right signal.
2. Weak battery or corroded cables. Low voltage can trigger the problem.
3. Worn ignition switch or lock cylinder contacts. Members suspected a 10-year-old replacement switch had worn out again.
4. Spark plugs or coils. If it cranks but never fires.

What it usually costs

No owner in these threads posted a final repair bill. The ignition switch recall repair is free if your car is included and it hasn't been done.

Is it safe to keep driving?

A car that dies right after starting is mostly an inconvenience, but if it ever shuts off while driving, stop relying on it until it's fixed. Verify with a mechanic.

DIY or shop?

DIY for the battery, cables, code reading and spark plugs. Ignition switch and Passlock repairs are usually shop jobs; some owners use the relearn procedure for Passlock.

Recalls, bulletins and complaints in plain words

• Related recalls: NHTSA lists these recalls touching this area of the Pontiac Sunfire: 02V070000 (1995-1997 model years, electrical system); 04V036000 (1998-2001 model years, electrical system). Check your VIN at nhtsa.gov/recalls. If your car is part of this recall, the dealer fixes it for free.
• In plain words: These recalls cover the ignition switch: if the engine doesn't start and you hold the key in START for a long time, high current can heat the switch enough to melt parts inside it. If your car is part of this recall and it wasn't done, the dealer fixes it for free.
• NHTSA complaints: 224 keyword-matched complaints for Pontiac Sunfire 1995–2005 (of 1,219 unique complaints queried, NHTSA complaints API by model year, queried 2026-10-24; keywords: stall, dies, shut off, won't start, no start, cuts out, idle, security, theft, passlock, ignition switch, crank). This counts complaints that mention these words. It is not a defect finding.

What owners report

• In My Daughters' 2001 Pontiac Sunfire - engine wont start on 30% of the keycycles on Car Talk, a 2001 Sunfire started and died after 1–2 seconds about 30% of the time. Members raised Passlock and the ignition switch recall; the recall work had been done in 2004. The owner found codes P1626 and P1632 (theft deterrent), freeze-frame data showing the fuel pump and injectors off, and a battery at 11.32 volts. Members said to replace the battery and clean the cables first, and that the 10-year-old replacement switch could be worn out.
• In 02 Pontiac Sunfire Ignition Enigma on Car Talk, a 2002 Sunfire 2.2 owner with similar no-starts had good fuel pressure in both conditions. A member said to check spark with an inline tester and pull the plugs before assuming a bad ignition switch.
• In Anti-theft system 98 sunfire on Car Talk, a 1998 owner's anti-theft light came on almost every drive and sometimes kept the car from starting. A member said the car has GM's Passlock system (1998 is near the changeover to Passlock II).

Quick tip

Start with a battery test. It's free at most parts stores and it solved more of these than anything else. Then read the codes before buying an ignition switch.

Vehicle focus: 1995–2005 Pontiac Sunfire with the 2.2L or 2.4L four-cylinder. The Chevy Cavalier has the same Passlock system.

Safety / mechanic note

If the engine ever shuts off while driving, stop relying on the car until it's diagnosed. Verify with a mechanic.