Fuel Pump?

[haux]

I drive a 2000 Toyota Camry, and it has over 167,000 miles on it.

A couple weeks ago I started the car, and it seemed to have what I would call a "weak start". I turned it, and it stuttered for a moment in hesitation. While it did this, the check engine light flickered a couple times. It did start, however.

Either later that night or the following night, the check engine light came on permanently. I took it to a shop for a diagnostic. The mechanic told me that a "Vent Malfunction" code popped up. He told me he wasn't sure what it could be without further looking into it, and he cleared the code to make the light turn off.

This was about a week ago, and until today I've had no problems. Now, whenever I quickly accelerate, or accelerate while turning, it seems as though the car hesitates when I hit the gas. If I press on it slowly, it seems ok. But if I just hit it, it feels as though it not getting any gas, because it does not accelerate for a moment, and then it goes.

This happened to me a while ago in my old 1977 Ford LTD. The problem there turned out to be the fuel pump. Does this sound like a classic fuel pump issue, or could it be something else. Someone told me that the "Vent Malfunction" message is a problem with a sensor of some sort.

This is unrelated, but the horizontal bolt that holds the alternator in place and connects to the vertical adjustment bolt somehow... bent. It's almost as though someone pushed on the alternator so hard that the bolt bent. This makes no sense to me, especially since I replaced those bolts just months ago.

I’m aware that when a car gets into such a high mileage, problems will arise. I just hope it isn’t anything too costly. Any assistance would be appreciated.

[zoni]

do you know the exact obd2 code?

[BlackCamSe]

could be throtele body or the IAC falve

[haux]

I do not know what the actual code is. The check engine light is back on, so I'm going to go back and make sure he tells me what the code actually is.


I may be able to explain the problem a bit better now... whenever I rev the engine in idle, the entire engine shakes for one second. Almost like a jolt...


This is what happens when I hit the gas... it feels as though it's jerking back and forth for a moment, then accelerates. The problem is much worse now than it was yesterday.

Also, sometimes it jerks for an instant even while not in motion. When I'm sitting at a red light, for example.

[zoni]

check on the end of your fuel rail.. there is a plastic cap covering the fuel pressure pulsation damper.. there is a small screw inside there with an oring around it. check and see if it has slipped out or something... other than that. a vacuum hose may be disconnected from something that controls the fuel system. check your hoses, even under the black plastic engine cover.

[haux]

I went back to the shop. This time, the code "PO300 - Random Multiple Cylinder Misfire" came up. Their recommendation was to take it to a dealer for a more thorough diagnostic.

So, the current order of events is as follows. First, a "Vent Malfunction" code of some sort came up with no apparent signs of a problem, and now a "PO300" code comes up, and the car is acting up. Whenever I rev the engine, the entire engine rumbles. This may also happen while the car is just sitting in idle.

What, if anything, can I check myself before taking the car to the dealer?

Also, where is the "fuel rail"?

[Mike Gerber]

With that kind of mileage and the random misfire code, I would replace the spark plugs and spark plug wires yourself, before doing anything else. If it's a 4 cylinder, it's pretty easy. On the V6, the back 3 plugs can be a bit difficult. Then see how it drives. If you are still having the problem, then take it to the dealer.

Mike

[zoni]

is there anything that happened before this? anything you changed at all? check your fuel cap. if the cap is off it will put up the first code:vent malfunction. which is p0446 by the way. this can aso be caused by a bad vacuum line. check your vacuum lines like i said before. the ones you should be concerned with are under the plastic engine cover.
this second code for multiple/random cylinder misfires is most likely caused by lack of fuel. this is probably caused by what happened with the first code.

[haux]

It's a 4 cylinder.

The thing is that.. 47,000 miles ago, I think that me and my dad did replace the spark plugs. This was back when my timing belt broke. We're not 100% sure, but we do think that in the process of getting the timing belt fixed, we did replace the spark plugs. I can always replace them again and see if that fixes the problem. Maybe we were going to but didn't.. I don't recall.

[zoni]

47,000, you didnt tell me that... damn i think it is time to replace the spark plugs for sure....

you should replace spark plugs like every 12-15k in my opinion.

[haux]

Regarding the bolt.. I later noticed that the bolt actually broke. I was on the highway and heard a clanking sound. Later I stopped and checked it... and no more bent peiece, just what was screwed into the slider.

I replaced the spark plugs earlier this morning. I also tried on new wires.. but they didn't make any difference. No more misfiring though; apparently the plugs were the problem.

However, I have noticed another oddity. The car seems to be hitting into much higher RPM's than usual. When I floor the gas pedal.. it shoots up to 5,000. I never recall it getting that high. Even during normal acceleration, it gets up to 3-4,000 much quicker than I ever remember.

The engine is also still shaking a little more than I recall. I say this because I never remembered the top right tube that connects to the radiator vibrating as much as it is. Also another tube that connects to the fuel injector is shaking. I only noticed this when I began having the PO300 problem, and it hasn't gone away.