So come to find out the "rattling/tinging" noise I've been hearing for the last couple of weeks is my engine pinging. I thought it was some tranny problem since it only occurs upon acceleration and can mostly hear it between 30-70 mph. I stopped by my dealer today and picked up the Corvette Tech guy which came to the conclusion of it pinging and most likely due to "carbon buildup" for which he wants to keep it overnight and do some thorough cleaning to the motor with some chemicals and what-not. I use ONLY premium fuel (granted here in Southern California we are screwed and our premium gas is only 91 octane everywhere) at Union 76, Chevron, and Shell gas stations. Never at the cheap-o ones. Anyone else think this is the culprit (carbon-buildup) or is there something else I should be considering? :confused: Thanks.

 

I have been using Union and Arco since 99 with no problem. If carbon build up is the culprit, let us know!

 

al please go to help forum and e-mail me.

 

Check the DIC for codes and make sure that your intake track is intact and the filter is clean!

Bill C

 

I took the advice of an older Vette enthusiast who knows his stuff and was very pleased after using the product he told me about. It may be hard to find but it is woth the effort. A small can runs about $20 and you should change the oil after you burn the tank of gas to which you add this stuff. It worked for me (2001 C5) and will probably do some good if your problem is not too severe. Hope this helps! Try a Google search for distributors in your area.

BG 44K Advanced Formula safely, rapidly and thoroughly removes engine deposits in carburetors, intake manifolds, ports and on valves. It restores flow in fuel injectors and cleans the entire fuel system. BG 44K Advanced Formula improves fuel economy and reduces exhaust emissions. It actually restores that "like new" driveability to an engine's performance and keeps it running better, longer and more efficiently. Add one 11 oz. can or bottle to fuel tank at fill-up. This product is a part of the BG TDC® program :thumbs:

 

It does sound like bad gas, but it has been doing this for more than the tank of gas you have in there now?Do you have access to any 104 octane unleaded race gas? If so throw about 5 gallons in there and see if it goes away, that will also help burn some of the carbon off the top of the pistons. I have had bad gas before, got some pinging, threw in some 104 and it went away.

 

I have heard good things about the GM decarb process but I thought you had to change the oil AND the plugs after that? I have heard there are two ways to do it... either let the engine suck it up through the PCV system through the intake or pour it in to each cylinder through the spark plug hole....

I just changed my plugs and don't want to do it again.... :)

Patrick :cheers:

 

Yes, I have been through about 4 tanks since this has started (at least noticed) and all with premium Union 76, Shell, and Chevron. Do you think the racing fuel over a complete fuel system cleaner is best?

The cleaning procedure they said they wanted to do was where they pour the stuff into each cylinder through the spark plug hole.

I'm going to run outside right now to check if there are any codes showing up. :leaving:
----

Okay...I am back: I had cleared ALL my codes this morning to see what would happen. Just checked and I have come up with these two codes:
BO-RFA U1000 H
BO-RFA U1064 H

These are the only two codes on the system and I have put on about 80 miles today since it was cleared. And yes, it has pinged constantly today.


[Modified by RskyBns, 8:29 PM 2/4/2003]

 

Im checking the code list now> Be back soon :thumbs:

 

BO-RFA U1000 H = Serial data communitations error. RFA module did not learn SOH message and recognition code from any of the following systems. BCM, IPC, OR PCM

BO-RFA U1064 H Loss of coms with the BCM Body Control Module. LDCM/ RDCM left and right door control modules and Left Seat Control Module LSCM

Sounds like you have an electrical problem. I would check for moisture in the passengers foot well under the cover.

Look there and let us know if it is damp or wet.

Bill C

 

It could be carbon build-up if you are pulling oil through the PCV or rings. What kind of oil consumption have you had?

I don't believe the Uxxxx communication codes are much to worry about. They are common.

How many miles on the car?


[Modified by TooManyIDs, 11:28 PM 2/4/2003]

 

none of these codes have anything to do with your pinging.

there's a great chance that your car will run fine after the dealer decarb's the motor. I would recommend doing some sort of PCV mod to eliminate oil getting into your intake from now on.

 

Im having the same issue. I saw a Technical service buliten about the ping detector's under the intake. they say it gets water in them easily, and to replace with new and add some rtv sealent around the sensors to keep water out.

Did you have any luck with your de-carbon from gm?

I am going to replace with 02 z06 intake and replace the sensors. Should i de-carb the cylenders at the same time?


[Modified by KEPRGHT, 3:52 PM 2/5/2003]

 

Also, the tech at the dealer said that there was a possibility it could be failing O2 Knock Sensors. I haven't taken it in yet, I guess I will do it tomorrow. There are 50k miles on the car now. And yes, since I have an '01 I do have oil consumption problems approximately 1/2 quart every 1000 miles. Also, if this does seem to be the problem with the carbon, pvc, etc.....should I remove the Blackwing and put the stock back on and/or do the PVC mod before I take it to the dealer?

 

The O2 and Knock sensors are TWO different things. The O2 sensors are in your left and right exhaust manifolds and behind the cats in your intermediate exhaust pipe. The exhaust manifold sensor/sensors could be fouled due to the fact that you state that you have an oil problem. If one is fouled the the other may be suspect. Your diagnostic program should be able to tell you if there is a malfunction in the O2 sensor operating perameters.

The knock sensor is a piezo electric sensor that listens for a tuned frequency (the same frequency that knock/ping develops and when it hears that frequency it will retard your timing until the event stops. Details on page 6-1162. It can retard up to 20 degrees. Your diagnostic program should be able to tell you if there is a malfunction in the KS sensor operating perameters. There are two sensors in a C5 and they are under the intake manifold.

If your car is under warrenty let them go for it.
If your spending your own money, I would recheck your codes using the diagnostic program using your Drivers Information Console (DIC). If you do not have any codes set, I would suspect that the engine is carboned up. De-carbon it PRIOR to spending tons of money at the tech's easter egg desires. NAPA sells a decarboning cleaner (dont quote me on the name "Sea Foam") that you can do your self. It's easy to apply and it works. You can squirt it in the same place that the engine oil entered in the first place the PVC vacuum port.

Dealer drive by trouble shooting can be EXPENSIVE!! :eek:

bill C

 

I've decarboned several motors over the past few years, using the GM Top End Cleaner. Sea Foam is basically the same stuff. Each time I sucked the cleaner in through a vacuum line going into the intake manifold.

If you do this, BE CAREFUL NOT TO LET THE ENGINE DIE while you're pouring it in, otherwise you could hydrolock the engine.

You also don't have to change the oil with the above method. If you pour it into each cylinder (as C5Tech described in the Tech Tips), then you DO have to change the oil. I think I'm going to try this one at my next oil change.

Also, I believe there's some truth to the old trick of running the engine at WOT occasionally to "blow the carbon out." What that really does is get the cylinder pressures up high enough to loosen/burn the carbon in the combustion chambers.

Hope this helps,
Mike

 

VetteDrmr

If this is true
" Also, I believe there's some truth to the old trick of running the engine at WOT occasionally to "blow the carbon out." What that really does is get the cylinder pressures up high enough to loosen/burn the carbon in the combustion chambers."
my combustion chambers should be clean enough to eat off of :D .
I run mine up to red line frequently and infact I have never had a carbon problem :thumbs:

I guess there may just be some truth to it after all!!

Bill C :cheers:

 

I have seen considerable carbon build-up on top of the pistons at 15,000 miles :yesnod: Do a decarbon procedure with GM top engine cleaner...There is also a PCM recalibration update to reduce spark knock :seeya

 

One question: I've read your tech tip on pouring the TEC into the cylinders, but what did you use to pour it into the spark plug holes?

TIA,
Mike

 

Mike you could use a large syringe, or a pump hand oiler

Bill