Starting Problems: What to check now?
Thread Starter
Racer
Joined: Nov 2002
Posts: 289
Likes: 0
Originally Posted by NVR BRNG
Can someone help me in continuing to troubleshoot my no-start issue?
I have an '00 'Vert MN6 w/ 41k mi. So. CA warm weather / weekender car with H/C, bolt-ons & custom PCM tune, other brake & suspension mods.
Current starting problem:
On 1st turn of the key to start, the engine will start and then immediately die, as if fuel / ignition is being cut off. It takes 2-3 restarts to get the motor to fire & run. This occurs regardless if whether the car is cold or warmed up. Once the engine is running, the car runs normally. On restart, it takes 2-3 cycles to get the motor to run.
1) No Codes.
2) No DIC messages.
3) Column Lock works normally. No CLB installed.
4) Normal Battery / Charging system.
5) Cleaned Pellets on both ignition keys.
6) I have resolved all recent DIC Codes, these only related to a low voltage IAT sensor, which I Replaced.
7) I replaced the ignition switch and reused the OE lock cylinder & OE keys. I did notice that some function returned with the new switch, such as the back up lights flashing when the "lock" button on the fob was pressed. I was hoping that the switch was going to resolve the starting issues.
8) G101 & G102 grounds checked out totally clean, so I stopped there.
9) Checked connection for neutral start switch underneath clutch pedal, but haven't checked voltage yet.
The only other recent change was that I had a new RPS clutch & flywheel + 3.90 gears installed @ A&A. Ever since I got the car back, I've been having the starting issue and initiated the above troubleshooting process, but the problem persists. Since the motor starts up then immediately dies, something is still shutting off fuel / ignition, but after 2-3 restarts it will fire up & run.
Can anyone advise on other things to rule out to resolve this issue?
I have an '00 'Vert MN6 w/ 41k mi. So. CA warm weather / weekender car with H/C, bolt-ons & custom PCM tune, other brake & suspension mods.
Current starting problem:
On 1st turn of the key to start, the engine will start and then immediately die, as if fuel / ignition is being cut off. It takes 2-3 restarts to get the motor to fire & run. This occurs regardless if whether the car is cold or warmed up. Once the engine is running, the car runs normally. On restart, it takes 2-3 cycles to get the motor to run.
1) No Codes.
2) No DIC messages.
3) Column Lock works normally. No CLB installed.
4) Normal Battery / Charging system.
5) Cleaned Pellets on both ignition keys.
6) I have resolved all recent DIC Codes, these only related to a low voltage IAT sensor, which I Replaced.
7) I replaced the ignition switch and reused the OE lock cylinder & OE keys. I did notice that some function returned with the new switch, such as the back up lights flashing when the "lock" button on the fob was pressed. I was hoping that the switch was going to resolve the starting issues.
8) G101 & G102 grounds checked out totally clean, so I stopped there.
9) Checked connection for neutral start switch underneath clutch pedal, but haven't checked voltage yet.
The only other recent change was that I had a new RPS clutch & flywheel + 3.90 gears installed @ A&A. Ever since I got the car back, I've been having the starting issue and initiated the above troubleshooting process, but the problem persists. Since the motor starts up then immediately dies, something is still shutting off fuel / ignition, but after 2-3 restarts it will fire up & run.
Can anyone advise on other things to rule out to resolve this issue?
’00 Vert with LS1, H/C & bolt-ons. CA car with 42k on the clock.
Problem:
Hard starting regardless of cold or hot. Starter turns engine no problem.
Engine fires & immediately shuts off. Takes 3-4 on/off ignition switch cycles before engine starts.
Engine runs normal once it is started.
Ruled Out:
PCM & SENSORS
No PCM codes
New MAT Sensor & MAF Sensor (replaced due to low voltage codes)
Throttle Position Sensor OK (with key ON, I can hear throttle opening & closing by actuating pedal)
Coolant Temp Sensor reads normal / OK on DIC / No Codes
ELECTRICAL & IGNITION
100% battery 690 CCA (Exide Orbital). (checked using meter and verified with out of car @ parts store)
Charging system OK (checked with meter and took car to get verified with auto parts store equipment.)
MSD Wires OK (checked using meter)
Coils OK (checked with inductive timing light)
Fresh Plugs - OK - light gray color
New Ignition Switch.
Grounds OK
Ignition Relay OK (swapped relays w/ same problem)
Completed BCM reconnect procedure per Corvette Forum method
FUEL
New Fuel Filter @ 33k w/ H/C install @ A&A Corvette
Fuel pressure OK. About 54-55 psi after 20 min. (Fuel is present in line, not air pressure)
Injectors OK. Checked on flow bench w/ No leaks – no flooding.
OTHER
No DIC messages or problems w/ Column Lock. Recall or Mod Not Done.
Clean air filter OK
Tried both ignition keys, same symptoms with both keys.
What else is there to check???
VATS?
If VATS is the problem, car would not start at all, right?
Can the keys be checked @ a dealer?
Melting Slicks
Joined: Mar 2005
Posts: 2,252
Likes: 181
From: NE OH
Cam position sensor. From my understanding, if you have a cam position sensor malfunction the PCM will 'guess' if you are on the intake or exhaust stroke and fire accordingly.
You can see the sensor fire with HP tuners or other diagnostic/logging software. You may also want to try a crank re-learn.
You can see the sensor fire with HP tuners or other diagnostic/logging software. You may also want to try a crank re-learn.
Thread Starter
Racer
Joined: Nov 2002
Posts: 289
Likes: 0
Originally Posted by muncie21
Cam position sensor. From my understanding, if you have a cam position sensor malfunction the PCM will 'guess' if you are on the intake or exhaust stroke and fire accordingly.
You can see the sensor fire with HP tuners or other diagnostic/logging software. You may also want to try a crank re-learn.
You can see the sensor fire with HP tuners or other diagnostic/logging software. You may also want to try a crank re-learn.
I'll do a search on the forum for more info here, but if you can post any links or details on how to check the cam position sensor and how to do a crank relearn that would be cool!
Thanks!
