Coil pack? Fuel pump? I’m baffled

toyota

#1

I have been baffled by my 2002 2.4L Toyota Camry. I’ve had a few coil packs replaced over the years. I have replaced all the spark plugs. Here’s my issue… My car will sputter when accelerating and idling. It usually is showing that there’s a misfire on some random cylinder. This happen for quite a while. I have been trying to figure out if there’s a pattern to it. For the past two months, i it usually is showing that there’s a misfire on some random cylinder. This happen for quite a while. I have been trying to figure out if there’s a pattern to it. I finally figured out a pattern that was as long as I didn’t let the gas gauge go under just above 1/4 of a tank of gas, it runs smooth as can be. All has been well for a while. Also, I noticed that if the engine light blinked, once it went back to solid, the problem with not happen. Then randomly Bam, I start having problems again. I don’t know if anybody knows what’s really going on with my car. I’m a single mom and can’t afford to spend a fortune more people replace this and replace that to figure out what’s wrong with it. Any advice?


#2

Don’t let the fuel gauge go below 1/4 of a tank.


#3

Surging,lack of power when accelerating,sputter etc are signs that the fuel pump is failing.The good news is that its easy to replace on your car because you don’t have to drop the fuel tank to replace it.There is an access cover under the back seat. 30 minutes is all it takes. rockauto.com has a fuel pump for $23(economy) that would suit your need.


#4

Yes, you have narrowed it down to a fuel issue and it sounds like the pump is easy to get to on this.

I had this happen once. The pickup tube was cracked so it started sucking air below a certain level. I went ahead and replaced the entire pump as this was a job to access and it was also old.


#5

I filled up yesterday when it was just above 1/4 tank. Drove home and another 40ish mile trip. All was fine until I was in the way to take my son to school today. It started again. I’m trying to convince my brother to fix it! Any way to check to make sure this is the problem for sure?


#6

You’re going to have to tee in a fuel pressure tester . . . I’m 99% certain this car doesn’t have a test port


#7

Can’t give precise diagnosis, but things to think about: a blinking engine light indicates a severe misfire. When misfire stops the light stops blinking. If it continues to blink, you should not drive the car as it can destroy catylitic converter. If it’s random misfire, it probably isn’t the coil packs IF it is coil on plugs. Cwatkin seems to have the best guess. Check the fuel pressure when tank is full. Then check it when tank is under 1/4 tank and car is acting up. If there’s a drop in pressure, you probably have a leak in the pump. Be sure to change fuel filter after pump change.


#8

What you’re describing are the classic symptoms of a weak fuel pump.

When the gas tank is full, the of level gas provides what’s called a pressure head. This pressure head assists the weak fuel pump where it provides the proper fuel pressure.

Then as the level of gas in the gas tank decreases, the pressure head decreases. The pressure head decreases to a point to where it no longer assists the weak fuel. And the engine starts running rough, sputters, and will cause a misfire due to the lack of proper fuel pressure…

Tester


#9

Certainly sounds like a problematic fuel pump, but it could be something else, either in the fuel system or the ignition system. Given the symptoms, after first checking the computer’s diagnostic codes, fuel pressure test is where I’d start.


#10

Get a loaner tool fuel pressure tester from a parts store and hook it up according to the instructions and test.