Engine code
P0021: Intake camshaft timing over-advanced (bank 2)
How this range is built
| Part of the job | Low | High |
|---|---|---|
| Parts | $60 | $500 |
| Labor: 1 to 4.5 hours × $125 to $175 an hour | $125 | $788 |
| Fees: shop supplies, disposal, diagnostics | $10 | $30 |
| Total, rounded | $190 | $1,325 |
The hourly rate is the BLS Occupational Employment and Wage Statistics, May 2025 average pay for this trade in Boston, $31.54 an hour, times 4 to 5.5 to cover what a shop bills (overhead, tools, insurance, profit). Parts are a band from budget aftermarket to the manufacturer part. Full method.
Not a repair shop, estimates only. Typical range, estimate. Not a quote. Your car, parts and shop change the number.
This is the range for the most common fix, vvt solenoid / cam phaser repair. Which repair your car needs depends on a proper diagnosis.
On the engine side without cylinder 1, the intake camshaft is sitting further ahead than the computer commanded. The variable valve timing system uses oil pressure and a solenoid to move the cam, so a failing solenoid, dirty oil or a worn phaser can all leave it out of position.
- Safe to drive?
- Short trips only
- Most common cause
- Dirty or low engine oil
The car usually drives, but may run rough and use more fuel. Check oil level and book a visit soon.
What you may notice
- Rough idle
- Poor acceleration
- Lower fuel economy
- Check-engine light
Common causes, most likely first
- Dirty or low engine oil
- Failed VVT solenoid
- Worn timing chain or stretched chain
- Failing cam phaser
Check this first
Check the oil level and age. Ask if the timing chain has been checked for stretch on a high-mileage engine.
Other repairs that sometimes fix P0021
| Repair | Typical range, Boston |
|---|---|
| Oil and filter change | $80 to $190 |
| Timing chain replacement | $1,250 to $2,850 |
| Camshaft position sensor replacement | $110 to $370 |
Before you pay
- Ask the shop what test showed this part is the cause, not just that the code appeared.
- Ask for parts and labor listed separately, and for the hours.
- Ask for a written OK before any extra work. Massachusetts rules require written authorization before repairs.
Got a quote already? Check it against the range. Want to see if your car has a recall tied to this problem? Check recalls by VIN.
Need to read a code yourself? OBD-II scanners on eBay (affiliate link, disclosure).
P0021 questions
What does bank 2 mean?
Bank 2 is the side of the engine that does not hold cylinder 1. On a V-type engine, that is the opposite bank from cylinder 1, and a shop can show you which bank that is on yours.
Is it the timing chain?
It can be, especially if you hear a rattle at startup, but the solenoid and oil are checked first because they are easier and cheaper. A scan tool timing test helps tell the difference.
Can bad oil cause this?
Yes. The system moves the cam using oil pressure, so dirty or low oil is a common trigger. Using the right grade and changing it on schedule helps prevent codes like this one.
How much does it cost to fix P0021?
The most common fix, vvt solenoid / cam phaser repair, has a typical range of $190 to $1,325 in Boston. It is an estimate built from parts prices and local labor wages, not a quote. Your car and shop change it.
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Code meaning written in our own words. Some codes mean different things on different makes, so check your scan tool or manual. Not a repair shop, estimates only.