I have 2002 corvette z06 with around 150,000 miles on it. The other day I was driving home from class and the engine started to idle really ruff. The check engine light stared flashing and I could get a whiff of what smelled like gas coming from somewhere. I pulled into the nearest parking lot and pulled my codes and the codes that popped up were P0300 h c and p0106. I limped the car to a local shop down the street and while driving it, it would sometimes die at a stop light or while idling. When it would die I pulled the codes again after clearing them and P0300 or p0106 would come up. The shop hooked a programer to it and it said "misfire." They replaced the plugs and wires along with the sensor, I think the MAP or MAF sensor not sure. They said the springs and valves all looked fine too. They also said they replace the intake gaskets, in that it came in a set for like $45. They said they started the car up and heard a ticking noise on the left side of the engine and so they shut it down immediately. Now when they went to go start the engine again it won't start or turnover. The shop also said it looked as if the starter was shooting sparks. They think it might be a valve issue in that it broke, bent or fell in. To check the ticking noise they want to remove the heads and check the valves. They said the springs and everything looked clean. Im really confused on what might be the problem, does anybody have any idea what the problem could be? Im really worried as to why the car won't start now and the ticking noise coming from the left side? Did a valve break and fall in and now I am out a motor? Any help would be greatly appreciated. I also have a borla x-pipe and exhaust that was put on around a yr ago if that makes a difference.

Matt

 

any help?

 

The bad news........the shop is throwing parts at the problem, instead of troubleshooting. Given that it is a 2002 LS6, you most likely have a broken valve spring, and have had the whole time.

With reference to the start throwing sparks....it may just be a loose connection, which is leading to a no start condition.

Get your car out of that shop, and to a qualified shop that knows C5s.

 

P0300 is RANDOM misfire, you need a different scanner to determine which cylinder(s) are involved. Z's are notorious for breaking valve springs-that would be the 1st place I'd look.

 

Ok. Would the valve spring cause the engine not to start as well? They say they want to manually try and start the engine by cranking it?
I told him about the valve springs and he said all looked fine and the reason he wants to pull the heads off is because of the ticking noise. I don't understand it.

 

If a valve bent, broke or fell in it would be obvious with a close inspection of the springs.

Find a better shop.

Ron

 

Now that you guys mentioned it about the valve springs, I did some research and when I looked at the car today and from the research I did, it seems as though he didn't even check the valve springs since all that looked like was done was he pulled off the engine covers.

 

You probably have two problems. Get your car out of there!

 

I will be doing that tomorrow ASAP!!!. what two problems do you think i have?

 

Valve springs need to be inspected....period. There is a tapping sound, so at least you know which bank to start with. Sparks coming from the starter may be a loose connection, damaged wiring,etc. Pull your codes, don't trust them to do it for you.


http://www.c5forum.com/ayc/dtcdic.php

 

So got it to another shop. A valve broke and damaged the heads. So now they are having to replace the head and valves and want to check the piston and crankshaft to make sure alignment is all ok. Anybody give me advice on new head, they are going to see if a machine shop can fix them but if not I need some advice on what heads to go with and what else I may need to do or get. Anything would be great.

 

With 150K on the clock, you might want to consider a new crate engine.

 

They found the problem in it being a spring that broke and caused a valve to break. Now there is a small ding in the head. The shop wants to see if a machine shop can fix the ding. I am aslo concerned with the internal of the engine now with the piston and cynlinder. I was wondering if anyone might have any advice on what way I showed go. If the head is able to be fixed should I get it fixed? If the head can't be fixed what would be a good set of heads to put on? If worst case scenerio and the head needs to be replaced along with the pistion and a possible bore, should I get it all fixed or do a crate motor and if so what would be a good crate or motor to be built? I am a college student and want to keep the cost low if possible yet I want to do it right the first time. Thanks again for all yours guys help

Matt

 

Matt,
Based on your description, I assume the shop has removed the head. If that's the case, they should be able to access the top of the piston, and the cylinder wall.

Sounds like you also need to have a discussion with the first shop. They owe you money back for the misdiagnosis, parts changed, etc. They also told you they checked the springs ! Sad reality, the spring was probably still holding the valve up when you brought it to the first shop. Since they could not figure it out, and continued starting/running the engine, the valve dropped.

 

Ok they should know by tomorrow what the deal is and I will have to go back to the other shop and have a little discussion with them about what happened and why they did what they did? Since the valved dropped any suggestions on my routes?

 

Good luck getting squat out of the 1st shop, especially if you paid them with the problem NOT gone. This is where people look at the computer output and not the OLD BASICS like vacuum to diagnose and engine.

 

Sorry Matt, hard to make a determination sight unseen. Make sure you get down to the shop, and have them explain the damage.....and take pics.

 

True! Im just frustrated on what am I am going to go about all this. This was not a good time for this to happen!

 

Ask for your money back and if they refuse, tell them you are going to take them to small claims court. Did you take it to MC Racing or Revline?

There's enough used stuff in the KC area you should be able to get it running again without a lot of expense. However, it is a good time for an upgrade or two. With the mileage you should throw a new set of lifters in there while they at least have one head off and have them check the camshaft for wear. New timing chain etc..

 

For us motorheads, a few good high quality photos will let us help you.
The damage could be minimal or massive depending on exactly what happened.

Your shop however might not like us/you telling them what we think needs done.

They will need to understand that a Z06 engine isn't an LS1 engine.

Keep us posted.

Ron