Ignition hesitation

[MikeRick]

Hi all,
My apologies, if this has already been answered, but i have spent the last hour searching the threads, to no avail.

1978 911 SC. When I turn the ignition switch to "start", it hesitates for a few seconds and then starts. The car has just started doing this a week ago, as temperatures have dropped, (-10C,/14F), in chilly Edmonton, Canada. When the car has been sitting over night, or a day at work, I turn the key, all power comes on, (radio, fuel pump, etc), but starter does not engage. Nothing. After holding the key in the start position for a few seconds, she starts cranking and fires right up. There is no hesitation if the car has sat for a few minutes or an hour, just after long periods. This morning, the temp has dropped to -15C/5F and nothing at all now. Everything powers up, but no start. There is no clicking like a dead battery. This is the first time in 3 winters that I've experienced this problem.

Thank you for your time,

[Alan Lindquist]

Hey Mike. Do you have a way to load test the battery to see if it has the right cranking power (Amps)? I would think that 15C weather would have come effect on the ability for the battery to deliver enough Amps. Have you confirmed that your ground strap from the chassis to the Trans is in good shape with good contact?

[DRACO A5OG]

+1 check battery, If you have AAA, they will come out and check the entire system as part of their service so you can focus on the failed/failing component.

I assume when you wrote "hesitate" you mean it cranks slow then catches???

[DRACO A5OG]

Also what weight oil is in her?

Hmmm, 3 years+ on the same battery???

[DRACO A5OG]

If you are inpatient, jump it and see if the extra amperage will wake her up as she use to.

[Steve@Rennsport]

Personally, I'd be looking for a high-resistance battery connection both at the battery, all the grounds, and at the starter.

Clean the battery posts and clamps with the proper tool, make sure all the grounds are bright & shiny, and load check the battery if its more than 3 years old.

[ossiblue]

Originally Posted by DRACO A5OG

+1 check battery, If you have AAA, they will come out and check the entire system as part of their service so you can focus on the failed/failing component.

I assume when you wrote "hesitate" you mean it cranks slow then catches???

I think he means there is a period of "dead" time when nothing happens (he wrote",...all power comes on but starter does not engage."

I agree with the others to check the battery. You also appear to have another issue if, as you posted, you fuel pump is running with the ignition switch in the "on" position. This does not contribute directly to your no-start problem, save a little amperage draw diverted from your starter, but it should be corrected when you get the other problem resolved.

[DRACO A5OG]

Oh I see now, stoopid old eyes

[MikeRick]

Thank you so much for the prompt replies.

Battery is a year old. System was checked when the new battery was installed, no issues.

Oil is 10W40. I was hoping to head to my shop to do an oil change today, for some winter weight. Oil isn't the issue for this situation, as I am not getting any cranking over. When it does finally start to turn over, turns strong. If it doesn't start first try, it will crank right away the next try, as if everything is normal.

As far as the fuel pump, relay was toast and had read about bypassing the relay. That was this summer and have had no problems as far as that's concerned. I did have a bad connection at the solenoid as well this past summer. Fixed the connection and checked ground strap and other connections. I realize that things can change and as soon as I get it started and into the shop, I will be going over these things again.

P.S. When I say "shop", I'm a sheet metal mechanic, not an automotive mechanic, and have access to a nice warm, clean bay, to work on my car.

[wwest]

Originally Posted by MikeRick

Hi all,
My apologies, if this has already been answered, but i have spent the last hour searching the threads, to no avail.

1978 911 SC. When I turn the ignition switch to "start", it hesitates for a few seconds and then starts. The car has just started doing this a week ago, as temperatures have dropped, (-10C,/14F), in chilly Edmonton, Canada. When the car has been sitting over night, or a day at work, I turn the key, all power comes on, (radio, fuel pump, etc), but starter does not engage. Nothing. After holding the key in the start position for a few seconds, she starts cranking and fires right up. There is no hesitation if the car has sat for a few minutes or an hour, just after long periods. This morning, the temp has dropped to -15C/5F and nothing at all now. Everything powers up, but no start. There is no clicking like a dead battery. This is the first time in 3 winters that I've experienced this problem.

Thank you for your time,

Clean/burnish the battery posts and connectors/terminals.

Corrosive materal "builds" between the posts and inside of the connections and often takes a bit of time to break down after a period of no current flow and then a high current load is added.

[MikeRick]

Battery posts are cleaned. Fingers are frozen.

[James Brown]

starter solenoid can also be "slow", crud, grease, gunk and cold can get in there and slow down the movement. try heating up the starter with a trouble light for a hour or so

[MikeRick]

Thank you to all that replied!

I did as James Brown suggested. Put some heat to the solenoid and she fired up. Thank you James.

Off to the shop to change the oil and see if I can't get things cleaned up some. Any suggestions for the solenoid? New one?

Again I thank you all. I've lurked around these forums quite a bit. Compared to other forums, (non-Porsche related), you guys are real gentlemen. Always happy to help and chalk full of info. My hats off to you all.

Enough with the gushing and sucking up. Off to get dirty!

Mike

[MikeRick]

Update: Cleaned battery posts, connection on solenoid. Can not find transmission ground strap. Have to admit that I did look very hard as everything is soaked from melted snow and couldn't get the car up very high. Test will be tomorrow morning, but, of course, the temps are supposed to go back up to around the freezing mark.

[DRACO A5OG]

It should be near the trans mount passenger side

[T77911S]

Originally Posted by Steve@Rennsport

Personally, I'd be looking for a high-resistance battery connection both at the battery, all the grounds, and at the starter.

Clean the battery posts and clamps with the proper tool, make sure all the grounds are bright & shiny, and load check the battery if its more than 3 years old.

+1

also could be a "slow solenoid" due to that "white stuff" what is that??

start with the cleaning

[James Brown]

20 years in chicago, you learn a thing or two