'97 Bonneville 40th Anniversary Edition Stalling (SOLVED)

[toba-dude]

When I stop at intersections or slow to make a turn, the engine dies. The same happens when backing out of a parking place, stopping, shifting into drive. I have also noticed when topping a hill on the interstate, the engine hiccups. The check engine light is on and I used my OBD II scanner and got a P1133 code which is not in the book that came with the scanner. I also got a P0303 code. Today I am replacing the H02S and cleaning the MAF sensor. Are there any other suggestions? This is the first problem I've had with this car and it has 240,000 miles on it. Last year I went cross country with it and got 600 miles per tank (Topping the tank). By the way, this is not a supercharged engine.

[RJolly87]

THe codes may be related. As you probably found online, the computer detected the o2 sensor is not switching (going from rich to lean) as it should, no matter what the computer commands (more fuel, or less fuel). It could be the o2 sensor is to blame, or there is something else causing the engine to run excessively rich or lean, so much so that the computer can't account for it. You also indicated a P0303, which indicates a misfire on cylinder 3. Replacing the o2 sensor and cleaning the MAF, and clearing the codes is a good start, but if it returns, I would check other things, like perhaps a stuck injector, bad coil, or faulty fuel pressure regulator (FPR). Most fuel system issues can be confirmed with a fuel pressure gauge.

EDIT: By the way, when was the last tune up, what work have you done, how long have you had it, how many miles have you put on it, etc?

[toba-dude]

I miss read the code. It is P0300 not P0303. I just changed the H02S, erased all codes and took it for a test drive (40 miles). I have no codes however, it still stalls when I stop. And there is a slight hiccup when going downhill. It's been close to a year since last tune-up where I changed the plugs, wires, air filter, fuel filter. I bought the car I 2006, it had 110,000 miles on it. It now has 240,180 miles on it. When it is running right, I can squeeze about 600 miles out of a topped off tank of fuel.

[RJolly87]

How much gas does it have in the tank when doing this, and does it go away when the tank is full?

[reb]

P0300 random multiple cylinder misfire. Probably a bad coil or ICM. Go to the Junkyard and pick up the 3 coils and ICM. Should cost about $50.00

If that doesn't fix the problem then go from there with the op suggestions.

[toba-dude]

It does it no matter how much gas is in the tank. Although, I did find gas in the vacuum line that goes to the fuel pressure regulator.

[RJolly87]

That is an indication of a ruptured Fuel pressure regulator, and is a known failure in that generation.

Replace it, today.

No, seriously, before it makes the manifold explode, or worse...

[toba-dude]

H02S, Fuel Pressure Regulator changed, MAF sensor cleaned and engine is running like new. No codes, no stalling, no hiccups!!!! Thank you for all the help.

[Bugsi]

Can you tack a [SOLVED] onto the beginning of your thread subject?