LS1 No Start
Thread Starter
Teching In
Joined: Jun 2016
Posts: 9
Likes: 0
LS1 No Start A couple of years ago my son and I rebuilt the LS1 in my 02 Camaro. I got an initial tune so he could hear it run before he went off to college. Life got in the way and I am just now getting the car on the road.
The initial tune worked OK and allowed me to drive around the block. Last year, when trying to start it (I start it every few months), it wouldn't start. With no time to work on it, I let it set for 6 months. I went to start it and it ran OK. The same thing just happened again, this time I am committed to getting the car on the road.
The crank sensor is working properly (tested the hall effect while rotating the engine), I have spark, I have fuel at the rail (~55 psi), and the injectors are opening/closing (noid light). Because of this, I think it may be a tuning issue.
The car was setup with a SD tune. It registers about 145 rpm on cranking. IAT and coolant temp are 75 degrees. The spark advance when cranking is 12.5 degrees
Any help or thoughts on where to start troubleshooting would be very helpful. I have been doing a lot of reading on tuning so I am familiar. I have also read the PCM and have TunerPro RT to make changes if necessary).
The initial tune worked OK and allowed me to drive around the block. Last year, when trying to start it (I start it every few months), it wouldn't start. With no time to work on it, I let it set for 6 months. I went to start it and it ran OK. The same thing just happened again, this time I am committed to getting the car on the road.
The crank sensor is working properly (tested the hall effect while rotating the engine), I have spark, I have fuel at the rail (~55 psi), and the injectors are opening/closing (noid light). Because of this, I think it may be a tuning issue.
The car was setup with a SD tune. It registers about 145 rpm on cranking. IAT and coolant temp are 75 degrees. The spark advance when cranking is 12.5 degrees
Any help or thoughts on where to start troubleshooting would be very helpful. I have been doing a lot of reading on tuning so I am familiar. I have also read the PCM and have TunerPro RT to make changes if necessary).
Last edited by toones; Jan 21, 2019 at 09:46 PM.
Just curious, how did you check that it has spark and fuel?
I've ran into issues multiple times with the LS where if it sits a long time, the injectors can get stuck. Have you tried spraying a little starting fluid in the TB to see if it tries to start?
I've ran into issues multiple times with the LS where if it sits a long time, the injectors can get stuck. Have you tried spraying a little starting fluid in the TB to see if it tries to start?
Teching In
Joined: Jul 2018
Posts: 31
Likes: 0
From: SoCal
The noid light will tell you if the injector gets the trigger to open, it won't tell you if it actually opens...
You may have stuck injectors, I see this occasionally, old fuel and inactivity make this happen. You can cycle them with a tool or a power probe and usually get them to work again.
You may have stuck injectors, I see this occasionally, old fuel and inactivity make this happen. You can cycle them with a tool or a power probe and usually get them to work again.
Trending Topics
Thread Starter
Teching In
Joined: Jun 2016
Posts: 9
Likes: 0
Thanks for the responses. I have a fuel gauge mounted on the rail. When I unplug the fuel pump relay and crank the engine, the fuel pressure drops from 55 psi. This tells me that the injectors are opening.
I pulled a plug to verify spark (last time I check with a inline light). The plug sparked just fine.
Any other ideas...please!
I pulled a plug to verify spark (last time I check with a inline light). The plug sparked just fine.
Any other ideas...please!
LS1 Tech Stories
The Best V8 Stories One Small Block at Time
6 Common C5 Corvette Failures and What's Involved In Repairing Them
Pouria Savadkouei
Retro Modern Bandit Pontiac Trans AM Comes With Burt Reynolds' Autograph
Verdad Gallardo
Top 10 Greatest Cadillac V Series Performance Models Ever, Ranked
Pouria Savadkouei
Top 10 Most Powerful Chevy Trucks Ever Made!
Hennessey's New Supercharged Silverado ZR2 Has 700 HP
Verdad Gallardo
Coachbuilt N2A Anteros Is an LS2-Powered C6 Corvette In Italian Clothes
Verdad Gallardo
Awesome K5 Blazer Restomod Comes With C7 Corvette Power
Verdad Gallardo
10 Camaros You Should Never Buy
10 LS Engine Myths That Refuse to Die
Verdad Gallardo
I'm in the same position with very similar problems. Car sat for a very long time (7 years). Finally get all the parts and now I'm battling a Open Injector Loop (P0200) and PO335 before the last Crank sensor replaced, now P0336 with the new (bosch - I think from Adv Auto) crank sensor. Replaced all 8 injectors (2 weeks ago) and just bought a second and now AC Delco Crank Sensor (last week), installed, checked voltage at the Crank Sensor (1.5 volts) checked wiring and all checked good. Work insane hours so working on my car can be challenging at times. A few more things to do and hopefully I will have corrected the crank sensor problem. . Any ideas will be greatly appreciated....
A stuck injector or two will still pass fuel by your test and could be enough for it not to start. Bad gas maybe? With earlier I would spray some quckstart behind the TB and see if it fires even very briefly to rule out spark
Thread Starter
Teching In
Joined: Jun 2016
Posts: 9
Likes: 0
I have tried starting fluid and it would not start. I pulled a plug and am getting plenty of spark. My next option is that maybe it is flooding so I will disconnect the FP relay and see if it fires with ether.
Thread Starter
Teching In
Joined: Jun 2016
Posts: 9
Likes: 0
This morning, I pulled the fuel pump relay, sprayed some ether behind the throttle blades and tried to start it. It stumbled during cranking, as if a few of the cylinders fired. I plugged the FP relay back in and it would start. I tried cranking with the pedal floored (PCM flood clear). It did not make a difference.
Thread Starter
Teching In
Joined: Jun 2016
Posts: 9
Likes: 0
So here is were I am: Still not starting
Help is still badly needed!
- Tried spraying starter fluid into the intake with the fuel pump relay disconnected Stumble, but no start
- Tried spraying starter fluid into the intake with the fuel pump relay connected. Stumble, but no start.
- With a noid light, I have verified that the injectors are getting power
- Pulling the plug, and cranking the engine, I can see spark across the plug gap
- Tested the crankshaft position sensor and it is giving the proper signal
- Tapped on each injector with a hammer to unstick it if it is stuck (I have actually had this work on another car)
- Tried a different PCM (the original from the car swapped out years ago)
- Checked timing while cranking and it is 12.5 degrees
- Swapped out ignition relays
- The railmounted FP gauge shows 55 PSI
- Disconnected the FP relay and cranked. The FP pressure drops.
- IAT and coolant temperature read properly using a scantool hooked up through the OBDII port
- If it was an ignition relay, there would be no spark
- If it was a stuck injector, it would run on ether
- If it was the PCM, there would be no spark or injector signal
- If it was flooded, it should have started after sitting overnight and attempting with the FP relay disconnected and a shot of starting fluid.
- Ignition timing is what is expected when cold starting (12.5 degrees)
- The drivetrain was rebuilt less than 200 miles ago so it should not be a worn cam or timing chain issue
Help is still badly needed!
Thread Starter
Teching In
Joined: Jun 2016
Posts: 9
Likes: 0
Another update...I have been doing some thinking. When I previously had this problem, the car started after sitting for six or so months. I don't drive the car much. I usually started every few months, pull it forward or backward to try to keep from getting flatspots on the tires, then shut it off. Since the car only has an initial tune, it ran extremely rich..When I pulled the plugs today, they were wet.
Because I don't run it long enough to burn off any initial fuel on the plug tip and;
the plugs were wet and;
because the car runs rich and;
last time this happened it corrected itself (after sitting long enough for the fuel to evaporate from the plug tip)
I think the plugs are fuel fouled and letting them sit overnight was not long enough for them to dry out. I pulled seven of the eight plugs and have them baking at 350 degrees for 30 minutes. After they cool off, I will put them back in and report back.
Because I don't run it long enough to burn off any initial fuel on the plug tip and;
the plugs were wet and;
because the car runs rich and;
last time this happened it corrected itself (after sitting long enough for the fuel to evaporate from the plug tip)
I think the plugs are fuel fouled and letting them sit overnight was not long enough for them to dry out. I pulled seven of the eight plugs and have them baking at 350 degrees for 30 minutes. After they cool off, I will put them back in and report back.
Moderator
Joined: Aug 2010
Posts: 7,323
Likes: 529
From: Ann Arbor, MI
Sounds like a good plan, especially since you already and thoroughly eliminated the usual suspects.
Before your last post, I was thinking either a weak or mis-timed spark. If the dried spark plugs don't solve it, I would swap in another crank sensor and carefully check its connector and wiring.
Before your last post, I was thinking either a weak or mis-timed spark. If the dried spark plugs don't solve it, I would swap in another crank sensor and carefully check its connector and wiring.
Thread Starter
Teching In
Joined: Jun 2016
Posts: 9
Likes: 0
Problem Solved This problem has been solved. The issue was that the plugs were fuel fouled. After baking them to dry them out (I baked at 350 for one hour), the car fired right up. I will start another thread to figure out why the car is over fueling, as it has to do with the current tune. Probably wrong injector pulse.
Thank you all!
Thank you all!
Moderator
Joined: Aug 2010
Posts: 7,323
Likes: 529
From: Ann Arbor, MI
I assume you are running it for at least a few minutes after each start? It can take a minute or two before the tune commands normal (lean) operation, the O2 sensors are fully warmed up, etc.
You are also welcome to post a tune here, although the vast majority of members here can only examine HP Tuners or EFI Live files.
You are also welcome to post a tune here, although the vast majority of members here can only examine HP Tuners or EFI Live files.