Hypochondriac

Hope I got the right From and not making a mistake. I'm trying to help my sister with her car. Her CEL came on. Seven error codes showed up. P0172, P0300-P03004 and P1399.

I've found out these codes can be caused by any number of problems. According to her, she filled the car with regular rather then 87/Plus like the manual asks for. She was going on a long trip so when she got to Jersey she filled it with 87. She noticed the CEL a day or two after that.

According to her the car also vibrates makes shaking noise when it's just started when it warms up it goes away.

P0172 can be fuel system too rich, can that have caused the other codes to pop up?

Would putting two bottles of Lucas upper system lubricant and fuel injection cleaner, and then filling up with 87/91 help?

Other then that the only thing I can think of is changing the spark plugs,wires distributor.

It's a 4 cylinder 2000 Honda Accord

phootbag

Probably related to the fuel that was put in. I wouldn't add any additives. I would remove as much of the current fuel as possible, fill the tank with known good gas and recheck.

Fuel type is critical since the engine is a chemical reactor and was designed with a particular fuel type in mind. I'd eliminate that as a possibility. If the problem persists, you may want to have the vehicle diagnosed by a professional since replacement parts can get expensive especially if they aren't needed.

phootbag

If fuel isn't the problem, tight exhaust valves can cause your symptom

Hypochondriac

Thanks, the gas is already a mixture of regular and plus. It's at half a tank. How should I tell her to remove the gas? Just drive until close to empty? Or should I tell her to take it to a shop and have them do it for her?

phootbag

Depends on how bad the symptom is. Bad misfires can ruin the catalytic converter over time and lead to costly repairs.

Nothing is a substitute for a qualified technician diagnosing the vehicle.

With the tank being half mixed, has the symptom gotten any better at all?

Hypochondriac

According to her it's the same. How important is it to fix this right away? Is it still ok to drive the car for a week? Take it it a mechanic next week?

phootbag

Don't know.

The P0172 sets when the fuel trim has reached maximum adjustment. This is bad because it indicates the vehicle is running so rich the computer can no longer compensate.

The misfires can ruin the catalytic converter.

I am not going to tell you the car is going to be ok for a week.

Hypochondriac

Thanks for the info, took it to a mechanic, he said I need the spark plugs replaced, and the fuel to rich is either the 02 sensor or I got poor quality gas and thats messing it up