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Car won't start :(
http://classiccamaroclub.mfatw.com/viewtopic.php?f=5&t=4689		 Page 1 of 2
Author:  78 Camaro [Tue Oct 13, 2015 9:13 am ]
Post subject:  Car won't start :(
Morning guys,
Went to go to work today but couldn't... any ideas on what i could be looking at fixing based on the below?
It's a 3rd Gen with 305 TPI.
I turn the key and it cranks, seemingly healthily. It turns over and over at quite a good speed (seemed normal compared to the previous starts), but it doesn't 'fire up'. I can smell fuel (unburnt) after cranking.
Battery says 12.45v
The volt gauge drops when cranking but i think it normally does this.
Any ideas on what to start looking at? I'm half thinking it's battery, but i got one new in October last year, so it's exactly 1 year old. It's an AC Delco direct replacement from John Wolfe. Don't know how long it will have sat on the shelf for, maybe that? Then again, it seems to crank quite well each of the several times i tried it.
Thanks!
Ray
Author:  Jamieg285 [Tue Oct 13, 2015 12:22 pm ]
Post subject:  Re: Car won't start :(
A bad battery wouldn't spin the engine properly. You're getting fuel, so it must be the ignition.

I know nothing about TPI, so that's as far as I can help.

Can you get to the plugs to check for spark?
Author:  78 Camaro [Tue Oct 13, 2015 12:29 pm ]
Post subject:  Re: Car won't start :(
Thanks Jamie,
I was thinking that too - low battery wouldn't keep spinning it so must be something else.
I will take a timing light out shortly and connect one end to ground, then clamp the other end onto the spark plug wire and see if it lights up. That would let me know if there's a spark, right?
Author:  chevy-stu [Tue Oct 13, 2015 1:45 pm ]
Post subject:  Re: Car won't start :(
I'd agree with Jamie, if it's spinning the battery and starter are fine, and if you smell fuel it's likely there's no fuel issues....so probably ignition related.
Author:  78 Camaro [Tue Oct 13, 2015 2:40 pm ]
Post subject:  Re: Car won't start :(
Thanks guys... well, went out at lunch, timing light at the ready etc. Thought i'd give it a test fire... it fired up! It kind of stumbled up the revs for about 10-15 seconds until it reached idle and kind of revved up and down a bit and sort of settled after a while. My dad described it as 'hunting' as it was struggling to adjust the timing.

So, not quite sure what that was about. I wonder if it's too with over fuelling / oil leak from valve seals? Reason i think this, is because i get a puff of smoke every time i start it. In the morning after being sat for about 12 hours, it always start first time easily. At work, after being sat for 9 hours, the starter runs for longer before it starts and the revs kind of rumble up to idle. I've read somewhere that when it doesn't start, it's in 'clear flood' mode, so wonder if valve stem seals are seeping in oil, or one or more injectors are leaking?
Author:  chevy-stu [Tue Oct 13, 2015 5:49 pm ]
Post subject:  Re: Car won't start :(
Could be MAF or TPS type fault.... electric sensor type issue.. ?
Author:  NeilTheCop [Tue Oct 13, 2015 6:21 pm ]
Post subject:  Re: Car won't start :(
Find this:
Image
Run the engine for a minute or so then stop it.
Now pull off the regulator vacuum line and stick your nose on it. If you smell or see petrol it's leaking internally.
If the regulator is leaking it will pull raw petrol out of the regulator and dump it in the intake. If there's enough petrol it will make the mixture so rich the plugs won't fire it, but you will smell the unburnt petrol being pushed out of the exhaust pipe.
If you turn the engine off and leave it overnight any petrol in the intake will have time to evaporate.
If you only leave it for a few hours, it won't
The 'hunting' and puff of smoke is the engine clearing the unburnt fuel out of the engine when it does start.
Those engines do have a flood clear mode. The engine has to be cranking and the throttle has to be more than 80% open, if it is the injectors are first cut off then they start working but at a very lean fuel/air ratio until the engine starts.
Author:  78 Camaro [Wed Oct 14, 2015 10:21 am ]
Post subject:  Re: Car won't start :(
Thanks for the advice, it sounds like you're onto something with the fuel pressure reg!

I will give the vacuum look and sniff test a go on Saturday. I do have a new fuel pressure regulator (adjustable) for it, but it's still at the previous owners house, i'll see if he can send it over... adding up 1+1 here as he already bought that for it, so maybe there's a good reason for doing so. Plus the puff of smoke and ok start overnight, struggled start after a short drive as you explain, adds up even more.

What type of fitting would the pressure gauge connector have? I'm tempted to put one of there now, especially if there will be an adjustable fuel regulator going in.

Started up normally today and took me to work, seemed to run the same as always but now i'm noticing the up and down idling which is hopefully down to the fuelling issue.

We put a timing light on it too, my dad said it looked quite advanced. The best (worst) description i can give is that the mark on the pulley was strobing about 3" before getting to the fixed timing teeth. The under bonnet sticker says timing should be set at 6degrees BTC, so i'm thinking that it is too advanced? I guess adjusting is done the usual way - twist the distributor?

Thanks for all the help!!
Author:  jon_buss [Wed Oct 14, 2015 1:50 pm ]
Post subject:  Re: Car won't start :(
It certainly sounds like the timing is out, but just to check. You had disconnected the advance wire hadn't you? You need to do that to time it properly otherwise the computer adjusts it for you, am at work so not sure of the wire colour (think brown) but it's a single connector near the passenger side top strut in the engine bay. Loops out of the main loom.

Hunting idle is often caused by the Idle Control Valve under the throttle body, just another thought. There is a process to reset / clean it, but generally it's a case of replacement. The fuel pressure regulator is common as well, but it's a sod to change as you have to remove the entire intake to access it.

My third gen once ran really badly on startup, I disconnected the battery for 10 minutes to reset the ECU then went for a drive so it could 'relearn' it's settings. Made it drive a load smoother. Never did it again, could have been coincidence or the reset could have helped. Worth a try.

I bought a fuel pressure gauge for mine (car now gone), it was supposed to be a 1/8 NPT fitting which I bought. But it never fitted mine, I assumed my fuel rail valve had been changed at some point. I can sell you a gauge, and connectors, fairly cheap if you want. But just in case I'd suggest double checking your valve is 1/8 NPT first if you do want it!

Cheers
Author:  78 Camaro [Thu Oct 15, 2015 2:17 pm ]
Post subject:  Re: Car won't start :(
Thanks for the advice on timing, i will give it a shot over the weekend as well. It certainly accelerates well so maybe it was advanced on purpose. Sticker on the bonnet says 6 degrees BTC so i'm guessing it will need to be strobing when the mark on the pulley is just hitting the timing clamp mark vs. it's current position which is almost at 1 o'clock when looking at the the engine straight.
Quote:
Hunting idle is often caused by the Idle Control Valve under the throttle body, just another thought
I'll give it a clean, never know, every little helps lol.
Quote:
I can sell you a gauge, and connectors, fairly cheap if you want. But just in case I'd suggest double checking your valve is 1/8 NPT first if you do want it!
Ye that would be great thanks, let me know how much you'd want for it. I'll see if i can figure out the fitting size in the meantime :thumbup:
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