Intermittent Starting Issues

[96SS10SS]

I’ve been dealing with issues starting my Camaro ever since I had the motor stroked to 416. I had the tune looked at and replaced the battery so far. Starter is being replaced next. At almost 95k, it probably isn’t a bad idea.

I had been in the practice of turning the key to start the car by clicking it all the way and not holding it. It would almost always show a “Service Stabilitrak” message but would start and run fine. Since the motor build, I noticed that it will sometimes give up after a short cranking attempt or will crank long if I hold it. Sometimes it’s a slow and labored crank and sometimes it’s a normal crank but doesn’t start right away or at all. If it doesn’t start right away, it shows the stabilitrak message, lights up all of the stabilitrak lights, and the tachometer stays at 0 and the car runs rough.

Recently I have noticed that my fuel pump does not audibly prime all of the time when I turn the key to ON. When it does, it starts fine. When it doesn’t, it either doesn’t start until it primed or runs rough. I experimented and found that if I pull the #5 and 20 fuses under the hood and put them right back in the car will start perfectly.

I am replacing the starter just to be safe.

What’s wrong with my car? Can anybody solve this mystery?

[JOURDAN]

Best to do a voltage drop...

Attach a digital volt meter to the battery or jump terminal. Start the car and take note of the voltage drop.

Try to catch it when starter is slow compared to fast. On a fully charged battery you should only see about a 2 or 3 volt drop more and it may indicate a faulty starter, poor connect, bad battery or binding.

[Spec]

Replacing the starter will get it done. Mine went out about the same time yours did (about 35-40k miles ago), and before I found the culprit, I replace the battery, ground cables, pretty much everything but... then the starter and the beast awoke again. Effortlessly, the Silver Surfer comes to life....

[camguynj]

Originally Posted by 96SS10SS

I’ve been dealing with issues starting my Camaro ever since I had the motor stroked to 416. I had the tune looked at and replaced the battery so far. Starter is being replaced next. At almost 95k, it probably isn’t a bad idea.

I had been in the practice of turning the key to start the car by clicking it all the way and not holding it. It would almost always show a “Service Stabilitrak” message but would start and run fine. Since the motor build, I noticed that it will sometimes give up after a short cranking attempt or will crank long if I hold it. Sometimes it’s a slow and labored crank and sometimes it’s a normal crank but doesn’t start right away or at all. If it doesn’t start right away, it shows the stabilitrak message, lights up all of the stabilitrak lights, and the tachometer stays at 0 and the car runs rough.

Recently I have noticed that my fuel pump does not audibly prime all of the time when I turn the key to ON. When it does, it starts fine. When it doesn’t, it either doesn’t start until it primed or runs rough. I experimented and found that if I pull the #5 and 20 fuses under the hood and put them right back in the car will start perfectly.

I am replacing the starter just to be safe.

What’s wrong with my car? Can anybody solve this mystery?

When it happens is it on both cold and hot starts?

[christianchevell]

Often starting problems are from starter heat stroke, and tuned also does not help in some cases even normal starts can be slower even with new starter and battery. My cars simple just throws the code if too hot, and I wait when cooler...no problem....wish I had hood vents and aftermarket starter, heat sock on starter no real help, a bypass of zero gauge wire around the positive terminal block in the engine compartment has helped some due to its inherent restriction with a change of the gauge of the wire there. Starters run about 200$ OEM, I replaced mine for nothing and I have about 30k....But yes headers notorious for starter problems and our heat shield pathetic....

[96SS10SS]

I appreciate all the ideas everybody is contributing. I’m definitely replacing the starter hoping that does it.

Originally Posted by camguynj

When it happens is it on both cold and hot starts?

It was more of an issue with hot starts after getting gas but now it’s cold starts too. When it was in the shop it started fine every time for them but sounded like it was straining a bit so they recommended replacing the starter.

Does the lack of fuel pump prime noise and pulling the ECU fuses mean anything to anybody? In a no start or start with dead tach and stabilitrak lights, why would it prime the fuel pump and start fine after I shut down and pull the fuses for a few seconds?

[96SS10SS]

Is the FPCM in the passenger rear panel the fuel pump relay? It appears there isn’t a traditional fuel pump relay in the underhood, instrument panel, or trunk fuse boxes. I’m trying to track down the intermittent priming issues. I was hoping I could swap relays to see if the relay is the problem but maybe the FPCM itself is failing.

[frankwjr]

+1 on starter...add an extra ground from the block...what kind of new battery? AGM style hopefully...do you have any other electrical modifications that could possibly be slowly draining the battery while parked?

and was there any fuel system upgrades? what fuel pump? good luck OP and report back!

peace...

[96SS10SS]

It has an ACDelco battery from the dealer. There are no electrical mods. It has the original fuel system and fuel pump.

[96SS10SS]

I just had the engine MIL light come on for the first time this morning. It never starts on the first try anymore in cold weather. It started after a few tries with the stabilitrak lights and dead tach so I shut it off and on subsequent attempts it would crank and crank but not start. I wiggled some underhood grounds to see if anything was loose (nothing obvious). I got back in and listened for the fuel pump, I heard it prime and it cranked fine but with the engine lamp on. Turns out to be a P0336 code for crank position sensor. First time I have seen the engine light come on. This car has been nothing but problems since I had the cam installed. I’m losing patience with it.

[frankwjr]

Originally Posted by 96SS10SS

I just had the engine MIL light come on for the first time this morning. It never starts on the first try anymore in cold weather. It started after a few tries with the stabilitrak lights and dead tach so I shut it off and on subsequent attempts it would crank and crank but not start. I wiggled some underhood grounds to see if anything was loose (nothing obvious). I got back in and listened for the fuel pump, I heard it prime and it cranked fine but with the engine lamp on. Turns out to be a P0336 code for crank position sensor. First time I have seen the engine light come on. This car has been nothing but problems since I had the cam installed. I’m losing patience with it.

who did the work and how long ago? wiggling the grounds does nothing...obviously the motor was pulled...how? out the top or cradle drop? (hey that rhymes! lol) so many Q's...

need to loosen clean and re-tighten the chassis ground connections..even the new starter will appreciate this..

as for how you are startin...I turn and HOLD the key until engine start...yes our cars have a built in SAFETY feature that will continue the startin process if the key is released too soon..if this is an issue not sure if this would make any diff...

and chasin electrical/ground probs can cause ALL kinds of codes to pop...lets work on what we can and possibly solve it with out loosin ur hair!

peace OP...l8tr

btw - how you like that cam?

[camguynj]

Originally Posted by 96SS10SS

I just had the engine MIL light come on for the first time this morning. It never starts on the first try anymore in cold weather. It started after a few tries with the stabilitrak lights and dead tach so I shut it off and on subsequent attempts it would crank and crank but not start. I wiggled some underhood grounds to see if anything was loose (nothing obvious). I got back in and listened for the fuel pump, I heard it prime and it cranked fine but with the engine lamp on. Turns out to be a P0336 code for crank position sensor. First time I have seen the engine light come on. This car has been nothing but problems since I had the cam installed. I’m losing patience with it.

Well now you where the problem is. Check the below link for really good P0336 code info. https://www.yourmechanic.com/article...-jamahl-walker

Highlighted summary

How serious is the P0336 code?
A vehicle with this trouble code occurring is unreliable, as it may be difficult to start or may not start at all.

Also, when a problem with the crankshaft position sensor goes unaddressed for an extended period of time, it is possible to damage other engine components. For this reason, the P0336 trouble code is considered serious.

[96SS10SS]

I took it to a shop in the Philly area for a cam and headers almost two years ago. About a year ago the engine blew due to an incorrectly installed rocker arm. They built a replacement motor and I paid for a stroker upgrade. Not sure how they removed it but I’m starting to think something electrical is loose, melted or chafed.

I had hot starting issues with it right away and went back for the tune to be adjusted. Starting issues (and oil consumption) have existed since last year after the build. It’s gotten slowly worse with cold weather and the check engine light never came on until this morning.

[96SS10SS]

Originally Posted by frankwjr

btw - how you like that cam?

The cam seems good to me, it has a nice lope to it and power gradually builds l until it really picks up around 3000 rpms. It’s my first car with engine work and it’s nice knowing it has the power to chirp the tires at relatively low rpms in 2nd and 3rd if you get on the gas. Traction can be an issue at times. Everybody beats me off the line when it’s cold out since I don’t want to spin sideways. I’ve had a few people comment on the cam lope at gas stations and lights and my wife always knows when I am getting home.