ck9887

2002 Z06 with 85K mi. Stock besides coolant bypass and ziptie intake mod.

Today while driving I pulled up to a light and noticed that my engine RPM's begin dropping and sputtering between roughly 400-800 RPM's. Within another 10-15 seconds, the car died. I attempted to re-crank it and the engine would crank but the car would not idle. After a few more seconds, the car would die. Battery is showing to have volts and sounded to have plenty of juice when trying to crank the car. I tried to crank it a few more times and it was reluctant to start. It eventually did start for a brief moment and would sputter then die. Trying to give it some gas after it cranked did nothing and would not get the RPM's up what so ever.

I did a visual inspection of everything. Battery terminals are good and no loose spark plug wires. I took off the air box and checked the function of the throttle body and made sure there was nothing blocking the intake. The car felt as if it didn't have fuel. My range is still showing 77 miles which seems about right considering I just got fuel a couple of days ago.

I didn't notice any check engine lights so I don't think it's throwing a code which leads me to believe its not any thing ignition related. I did notice that I did not hear the fuel pump surging as you typically would when turning the key to the on position. I hear something clicking as the fuel pump usually does but it doesn't sound as if its sending any fuel through the lines like you usually hear.

So needles to say, I had the car towed to a friends house, 65 miles from where I was stranded at. Insurance is supposed to pick up that bill thankfully. I'm wondering if my assumptions about the fuel pump sound likely or if there is anything else that would cause these symptoms. I have heard of dealerships charging insane amounts to do a fuel pump since I believe it's in the fuel tank but anyone know what a reasonable cost would be?

Thanks for any help.

SacCityCorvette

Maybe you broke a valve spring.
Its a common problem for are 02 Zo6's.

ck9887

Don't know how likely that is considering I wasn't driving the car hard at the time it started acting up... I was coming to an idle at a light. Guess I'm not ruling anything out at this point tho. Maybe some more will chime in.

SacCityCorvette

Do a search about the Zo6 breaking valve springs. A few guys were idling or just cruising down town when they broke a spring. Its just a defective spring that causes it. The symptoms were similar to yours. I never experienced it because I changed my spring as a precaution. Some people even dropped a valve when the spring broke. Hopefully its just something simple and easy to fix.

ck9887

Considering the car has 86K mi, isn't it likely it would have failed sooner if it was a defective spring?

SacCityCorvette

Sooner or later. Its easy to check if its a spring, just pull the valve covers and look at the springs. Then you can eliminate that part of your diagnostic. Check for any codes as the first part of checking things out.

ck9887

Roger that. I was supposed to take the car in Friday for a clutch install. So hopefully I can just have it towed to the shop and have them diagnose it there if I can't figure it out.

If I dropped a valve, might as well do a cam swap while I'm in there.

SacCityCorvette

I hope you didnt drop a valve, it can cause a lot of damage. I think if you did you would hear it making noise. You might let the shop know about the valve spring issue with these Zo6's. Hopefully its the fuel pump! Good luck!

hotwheels57

Are you in the habit of running your fuel level that low? How certain are you that you actually had "77 miles" of fuel available to use? If I'm not mistaken, that reading is an average not an absolute.

Fill up your tank(s) and hope a low fuel level is the issue.

The electric fuel pump needs fuel to keep cool. If you drop the fuel level beyond a certain level the pump will run hot. Do that enough times and you risk the chance of burning up the pump.

Your fuel filter/pump is inside your fuel tank (I think that's correct with an '02). It's supposed to be good for 100k miles. That also is not an absolute if crud/contaminants in the bottom of your tanks is being sucked up due to low fuel level.

Another thing to consider is you have two tanks in your car with a transfer tube between. There's a separate pump to transfer fuel from one side to the other. There is a chance of a failure there preventing fuel from being transferred from one side to the other.

Use search or search this forum (in the red banner) in C5 Tech. Use keywords "fuel pump transfer tube failure". There are many threads on that topic.

Here's just one...
http://forums.corvetteforum.com/c5-t...m-failure.html

ck9887

I'm pretty sure the estimated range was pretty accurate based on how much gas I had put in the car just a couple days prior. I have run the car with the low fuel reading coming up on several occasion.
I will look into those threads.

Thanks for the info.

Aerovette

Throttle position sensor ???

Mr.Bill

The first thing I would do is check that it is getting gas, Turn on the key and see if you have pressure at the schreader valve on the fuel rail, It sounds like it isn't getting gas.
Mr.Bill

SacCityCorvette

Good idea Mr. Bill!

ck9887

I did check the valve on the fuel rail and it does appear to have pressure... Not sure it this totally rules out the fuel pump or not.

02z06dave

Sounds like a fuel pump to me.

crainholio

Buy a $20 fuel pressure gauge from the parts store and get a measurement during initial key-on and while cranking. Should show 55psi to 60psi.

Valvespring theories posted above are highly unlikely, unless you're willing to believe that all 16 of them failed simultaneously.