Bartric

I recently purchased a C5 and after a few days of being able to really test it, I have noticed that when I get on the throttle through about one or two gears, my clutch will not spring back up until I pump it for about 20-30 seconds.

Also, when I run the codes for the check engine light I get:
P0430: Catalyst System Efficiency Below Threshold
P1220: TP Sensor 2 Circuit Conditions
P1221: TP Sensor 1-2 Correlation Conditions
P1516: TAC Module Throttle Actuator Position Performance

The guy told me that it may need a throw-out bearing soon, and that it needed an O2 Sensor, would those be the causes of these problems? Any help is appreciated.

Bill Curlee

What C5 do you have???

How many miles???


What modifications do you have??????

Whats your mechanical ability and do you have a set of service manuals????????????????



CLEAR ALL THE DTCs and see what come back are they history or CURRENT TDCs?????/

You should up date your avaitar data.

Reading DTCs

READING YOUR Engine Diagnostic Trouble Codes (DTC)

This procedure should be carried out any time you experience a problem with your C5. Most inexpensive store bought aftermarket code readers will ONLY read power train DTC’s. Reading the DTC’s with the C5 built in code reader will allow you to read ALL the modules in the vehicle.

The Diagnostic Display Mode is entered with the following procedure:
1) Turn on the ignition but don't start the engine.
2) Press the RESET button to turn off any warning messages. (i.e. door open, trunk open ect)
3) Press and hold the OPTIONS button
4) While holding OPTIONS, press FUEL button four times within a 10 -second period.

Initially, the on-board diagnostics go into an Automatic Mode which will cycle through each module and shows diagnostic codes in a pre-set sequence: PCM - TCS - RTD - BCM - IPC - RADIO - HVAC - LDCM - RDCM - SCM - RFA. All codes will be displayed for each module. ( i.e. PCM = 4 codes) If none are present in a given module, you will see No More Codes on the display.

There are two types of diagnostic codes, Current and History designated with a letter suffix, “C” or “H”. A current code indicates a malfunction is present in the module displaying data. A history code indicates a problem existed sometime in the last 40 or 50 ignition cycles. When not accompanied by a current code of the same number, it's potential evidence of a previous problem, now resolved, that was not removed by clearing the codes. More likely it's an indication of an intermittent malfunction.

Intermittent codes are the most challenging of the diagnostics. An intermittent code may have happened once, may have happened more than once but is inconsistent or may be happening on a regular basis but not at the time the codes are displayed. History codes can also be caused by a current malfunction in a system that is not operating at the time codes are displayed. An example is the rear window defogger which doesn't operate until the Body Control Module detects engine rpm. For history codes set by a module that does not operate with the key on and engine off, a special diagnostic tool called a Scan Tester is necessary to properly diagnose the malfunction.

Once the system has displayed all modules, it goes into the manual mode which allows selection of each module using combinations of Driver Information Center buttons. Manual mode can also be entered during the automatic sequence by pressing any button except E/M. Once the display shows Manual Diagnostics, select a module by pressing the OPTIONS button to go forward or the TRIP button to go back. Once a module is selected, a code is displayed, and if more than one are present; press GAGES to go forward or FUEL to go back.
To exit the diagnostic mode at any time, press E/M. If you want to erase codes in a given module, press RESET To reset the codes once in manual mode, press and hold RESET until it displays NO CODES Press OPTIONS to go to the next module. Repeat the steps until you have reset the codes in all the computer modules.
NOTE!! Only reset the codes IF you want to - it is NOT necessary to do this. Clearing a code does not repair a problem. You are simply erasing the evidence of it in the module's memory. If you clear the code/s, and extinguish the Check Engine Light, your emissions status ready will NOT allow you to pass an emissions test until you have completed the required driving cycles. There are a few body module DTC’s that if set will prevent the module from operating properly. Once the DTC is cleared, the module will return to full function. This is not true for power train DTCs.

If you have never read and cleared your codes, there will probably be a lot of old history DTCs. It is recommended that you clear your codes and see if any come back during a driving cycle. Those are the ones that you need to concentrate on diagnosing.

Once you have the codes, the next question is: What to do with the information?
First, consult the factory service manual. Any serious C5 Do-It-Yourself owner should invest in the Corvette Service Manual of the appropriate model year. The Service Manual is really a requirement if you want to understand and work on your C5.

You can read the DTCs while the engine is running. If you turn the engine OFF and then back ON, that can clear some DTCs that may be important with identifying a problem. One example is a Misfire DTC (p-0300) If the engine is shut down, the DTC will clear.

These are some very good C5 Diagnostic Trouble Code (DTC) explanation web sites!!! They also explain how to read the DTCs

Here are some very good sites that explain what DTC mean:

http://www.gearchatter.com/viewtopic11755.php

http://www.obd-codes.com/trouble_cod...d-ii-codes.php

Make sure to include the H or C suffix when you post your DTCs!!

tblu92

Sounds like you need to "bleed " your clutch--It has a hydraulic system similar to the brakes
As far as your codes--Clear them 1st as Bill says- See if they return-- Sounds like you may have a bad 02 or if you have long tubes--the P0430 is a common code for LT's -code must be permanently deleted---The TAC ant TP codes most always are a result of mods that increase HP beyond a ceratin airflow maximum--- To eliminate them permanently you just need to INCREASE the entire "predicted airflow table by 30% (ELILIVE table # C6101)
So a tune is needed

lucky131969

Before entertaining a bleed, check the level in the clutch master cylinder reservoir. That will tell you if there has been any fluid loss. If the level is low, then the next step, is to get under the car, and see if there is a leak from the bell housing.

Bartric

Okay, I checked all of the codes, and as you said, there were a lot of history codes as well as a few current ones, I only checked it while it was not running, but cleared all the codes afterward to see which ones reappear after driving for a day or so. Here is the list along with the section they appeared under:

10-PCM:
P0430 H C
P0704 H C
P1220 H
P1221 H
P1516 H

38-RTD:
C1790 H C (Special note at end, Also aware that the Ride control switch isn't working but not sure what 'Out of Range' means)

A0-LDCM:
B2282 H
B2284 H
B2272 H
U1064 H

A1-RDCM:
B2253 H
B2203 H
B2205 H
B2283 H
B2285 H
B2273 H
U1255 H
U1064 H
U1016 H
U1096 H

B0-RFA:
U1255 H
U1096 H
U1064 H
U1016 H
C2110 H C (I am already aware of the Passenger Rear TPMS)
C2115 H

The special note about the one above is that even after clearing off all the codes it reappeared immediately.

I believe this Corvette is a base model, it has 133,XXX miles, modifications (from what I was told) are an after market Fast LS1 intake, and an aftermarket throttle body. My mechanical abilities are only limited to what tools I have and the amount of time I have. If I have instructions I've never had a problem doing any work myself. I do not own a service manual unfortunately.

Also, occasionally when I stop I have noticed the smell of anti-freeze. Possible reasons for this other than a leak?

Also, along with your list of helpful sites, I found one that lists even more codes and should be stickied if it hasn't already been:
C5 Fault Codes

Bartric

I believe you're referring to the tiny reservoir near the driver side back of the engine that you put the clutch fluid in? If so, it is full as it has been over the past 3 days of driving it, although it feels as if it may have had a little bit leak out and run down it due to being slightly wet.

Bartric

Okay, so after clearing the codes on my lovely 99' Corvette and driving it for quite a while I have a list of all the codes that reappeared. I just need help figuring out what some of the problems are.

10-PCM:
P0704 H C - Clutch Switch Circuit (M/T)

38-RTD:
C1790 H C - Ride Control Switch (Out of Range)

99-HVAC:
B0361 H - Left Actuator Feedback Short to GND

B0-RFA:
U1096 H - Loss of Communication with IPC
U1064 H - Loss of Communication with BCM
U1016 H - Loss of Communication with PCM
C2110 H C - Passenger Rear TPM Sensor Malfunction

Along with this I have noticed two things about the car that I would like help with diagnosing:
1. When I run the car hard (somewhere above 4 grand) my clutch sticks to the floor until I pump it for a few seconds. Could this be cause by the Clutch Switch Circuit?
2. I occasionally hear a brief squeal/chirp coming from the car. I've heard it at many different times and different situations, just cruising around I've heard it and other times while taking off as I'm letting out on my clutch.

What could be the cause of all of this stuff?

Quicksilver Vert 01

With 133k miles on the clock, I'm betting on dirty or burned ignition switch contacts, causing low voltage, and loss of communication, to voltage sensitive electronic modules.

I would start by either taking the switch apart to clean the electrical contacts, or replacing the ignition switch with a new one.

Bartric

Okay, so after doing a little research about the clutch switch I found it on my car and it doesn't appear that my clutch actually comes up and pushes the switch in, so I think the switch just needs to be adjusted and unless this switch does something major (other than just sensing when my clutch is depressed) and alters something performance-wise I hardly see it being any problem at all.

If anyone has any insight as to what exactly the clutch switch does, other than just sensing clutch position (engaged/disengaged) please let me know, I will be looking into fixing this small problem sometime soon if it's something I can alter myself.

Any ideas as to what might be causing my clutch to stick to the floor when ran hard would be appreciated (my only guess is slave cylinder going out and not providing the back pressure needed but this is just a guess). Thanks guys.

Bill Curlee

The switch turns OFF the CRUISE CONTROL when the clutch is depressed to keep you from over revving the engine. If you don't fix it, the cruse wont work.

Your last hope is to remove the EXHAUST SYSTEM and tunnel plate and BLEED/FLUSH the clutch so you get all new fluid in the system.

It will take significant flushing to get the system clean and theres ZERO guarantee that the process will relieve your issues. Give flushing a try. Hell,, it beats clutch replacement!

BC

Bartric

Well, this explains why my cruise control doesn't work.

I will try flushing it and hopefully that will fix it, I'm pretty certain it's not the clutch because there is no slippage at any rpm or any throttle, but definitely something in the whole clutch system. Anyway, I'll get around to flushing it whenever I get the chance to and see if that fixes it. Any recommended way to flush it?