Posting for a Freind he took his vette for a ride it spit and sputered so he turned around went home tried again ran OK he went home later went for another ride it spit again went back home looked at the intake it was loose he fixed that went for another ride he got down the road and it quit on him trailered it home it runs for 5 seconds then quits try to restart it has no spark he changed the cam sensor and crank sensor no change codes come up reduce engine power traction control and map sensor he checked batteries and grounds what could it be ????

 

Please clarify the runs for 5 seconds and has not spark. It cannot run with no spark.

Never seen MAP Sensor display on the DIC message?

Are you sure he checked the ground for the PCM. It grounds on the engine block.

He may need to look at the PCM and see if he has any battery acid issue on the connectors.

Not at home now.

Who changed the sensors? There are specifics on what needs to be done to make new ones work once installed.

 

First off,,, Some "PERIODS" in your post would make the context of your post a little clearer and easier to read and understand.

All the things that are happening should have presented some PCM Diagnostic Trouble Codes (DTCs)

When the engine goes into Reduced Power, that alone has associated DTCs.

How are you reading the DTCs??

Are you reading them using the Instrument Panel Condole (IPC) thru the Drivers Information Console (DIC) display when the problems happen without turning off the ignition?

Bill

 

Well the car will start for 5 seconds like I said it quits then restart it has no spark let it sit for a beer then it starts runs for 5 seconds quits then restart no spark I'm not sure if he checked the ground going to block but last night he took the batteries box out its clean as a whistle he check all grounds under car he even got to the computer and check for good connections he had a stroke 7 years ago it's hard to under stand him when he talks but he can take a car aapart paint it and put it back together so he has knowledge he put a super charger on this vette 2 years ago 583 horse on ls1

 

What Bill Curlee means is something like this (hope I interpret everything you typed correctly):


Well the car will start and run for 5 seconds like I said. After those 5 seconds it quits and then upon restart it has no spark.

I let it sit while I fetched myself a beer. After that, engine started and ran, again, for 5 seconds. Then it stalled. Upon restart yet again there was no spark.

I'm not sure if my friend checked the grounds going to the block. However, last night he took the battery out to check. It is clean as a whistle. My friend has checked all grounds under the car and he even got to the computer and checked whether the connectors are good.

My friend had a stroke 7 years ago. It's hard to understand him when he talks but he can take a car apart, paint it and put it back together so he has the knowledge. He put a supercharger on this vette 2 years ago: 583 horsepower on the LS1 engine.

 

Sorry my previous post could be interpreted so that you should wait what the forum tech guys have to say about your previous post, whereas in fact the forum tech guys are waiting for you to write down the DTC's.

 

What do you mean DTC's

 

Aha! First client for my new thread

Please click here.

 

1278 was one, engine reduce power, was another traction control came up also trying to call him if there was more grrrr.

 

Here is how to pull the codes and correctly identify them:


READING YOUR C5 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.

NOTE and a WARNING. You can read the DTCs while the engine is running. I pull mine up all the time while driving.
WARNING. Don’t become distracted while reading DTCs while your driving and cause an accident!!!!! Use common sense and drive safe.

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!!

NOTE!!! Start the car and let it idle. Then take it for a drive and cause the problem to occur. When you return home pull the codes BEFORE you shut off the engine.


Do NOT discount the codes with the H following them. They can provide an audit trail for issues going on with the car. They ARE important in diagnosing problems.

Post ALL the codes that you pull with the engine running..........

Some codes go away WITHOUT setting an H code when you shut the engine off. I suspect you will have several codes that will show C or HC that do NOT show when the engine is turned off.

 

Without being able to see ALL the DTCs that are being displayed, its very difficult to make a proper diagnosis.

Its easy to tell you to start replacing parts. Its BAD for your wallet. Besides,, Parts may not be the issue. It could be something as simple as a bad connection.

Please post all the DTCs. If there are a LOT of DTCs, clear ALL of them and see what comes back when you start the engine.

BC

 

The only
Code he said came up was c1278 and like I said the car runs maybe 5 seconds

 

The DTC is defined as: 28-TCS: C1278 - TCS temporarily inhibited by PCM.

It has NOTHING to do with an engine shuting down.. The DTC is a result of something that is happening in the PCM.

Either the person retreiving the DTCs isnt doing it correctly, isnt seeing other symptoms like (SECURITY LIGHT) flashing, Other messages in the DIC or the car thinks that it is being turned OFF with the key.

The electrical shut down without actually doing any operator input would indicate that the IGNITION SWITCH or and ignition powered circuty supplying ignition power to the PCM and BCM are losing power. Just like you turned the key off.

Without actually using a DC Volt Meter and reading the power to the fuses supplying the ignition voltage to the PCM and BCM, its just a guess.

Here is a post that I started that deals with ignition switch failure and repair. AGAIN,, Im not saying that this is THE PROBLEM. Its just one COMMON issue that can cause what you are seeing that needs to be ruled out or determined to be an issue.

- C5 ignition Switch repair - http://forums.corvetteforum.com/c5-t...ch-repair.html


Bill