1978 911sc issues

[porsche911girl]

Hey all,

Long time away, I know but I'm back. I am having the following issues with my 78 911SC I was hoping you might help me out with.

First issue: cold start, or rather, lack thereof. When cold the car will turn over but die immediately unless the gas is pressed to keep the revs up. Runs fine when warm, but there is a loud knocking noise coming from the engine bay and the engine runs really rough when it finally starts.

Second issue: hot air at passenger side feet. No matter if the air con is on or off, there is hot air that is constantly blowing out at the passenger side footwell.

Third issue: Rapid turn signals. The turn signals blink rapidly when on. I've read that a new relay will fix this. Is that true?

Fourth issue: It can be hard to get into both first and second gears.

Thanks all very much in advance!

The problem is that my dad bought this car as a fun car but he is very poor at keeping it maintained and I think he thought it would be a car that would start up every time with no issues but he's found out that you can't just store it in a garage at your second house and not use it for months on end, and expect it to be fine like any modern car would be.

As you can imagine, it is very frustrating to me to see it sitting there but I haven't mastered the art of driving a manual so I can't do anything about it.

He has disconnected the battery so maybe a new battery is in order as well as a good tune up.

[stevej37]

I am not the best to answer your questions but...please don't start it or drive it until you have someone look at the reason for the knocking noise. Do you know anyone in your area that works on or owns a similar car?

[tirwin]

1st issue. You should not need to use the throttle to get the car to start. There are lots of potential issues. Could just need a tune up, but more than likely needs a thorough going over to check fuel pressures, vac leaks, ignition system. You will need a troubleshooting plan of attack. The knocking sound is more worrisome. Could be almost anything from minor to major. Need more data. Maybe a local Pelican could drop by to have a look. I'm told that some people work for adult beverages.

2nd issue: Heat. The issue is most likely the passenger side heat flapper box is stuck open. Could be rust or a broken cable. That would require getting under the car to inspect.

[Bill Jennings]

Perhaps you could record a video of the engine running and post it here so we can hear the knocking noise and rough running issue?
However it might be prudent to try turning the engine over slowly by hand and having another listen to it before you try starting it again.
If you cannot do either of the above get a porsche mechanic to look at it or find a local Pelican to come and help!
You really must discover the cause of the knocking before you do anything else!
Cheers
Bill

[darrin]

third issue -- rapid turn signal flashing, this is "by design" if one of your turn signal bulbs has burned out -- check to confirm that you don't have any blown/dead bulbs. You can get a different relay that won't rapid flash when a bulb's burned out, but why?

fourth issue -- sounds like your clutch isn't fully disengaging and/or your shift linkage needs adjusting.

Unless you're familiar with working on a 911, your issues might all be best addressed by an aircooled porsche specialist/shop --

[RSBob]

If funds are limited, I suggest that you host a Pelican Work Party at your house some Saturday morning and provide coffee and donuts and maybe pizza for lunch. Have people bring their tools, jack stands and knowledge. You may want to get tune up parts in advance like new plugs, cap and rotor, condenser and points if your car still has those. If you get 5 or 6 knowledgeable people there they could get most of what you have sorted pretty quickly. Pelicans are a good group and like helping fellow Pelicans out and especially teaching newbies.

The gear issue hopefully is an easy adjustment. If not, you may have to live with it or spend some hefty dollars. Best of luck.

[ossiblue]

Originally Posted by porsche911girl

Hey all,

Long time away, I know but I'm back. I am having the following issues with my 78 911SC I was hoping you might help me out with.

First issue: cold start, or rather, lack thereof. When cold the car will turn over but die immediately unless the gas is pressed to keep the revs up. Runs fine when warm, but there is a loud knocking noise coming from the engine bay and the engine runs really rough when it finally starts.

Second issue: hot air at passenger side feet. No matter if the air con is on or off, there is hot air that is constantly blowing out at the passenger side footwell.

Third issue: Rapid turn signals. The turn signals blink rapidly when on. I've read that a new relay will fix this. Is that true?

Fourth issue: It can be hard to get into both first and second gears.

Thanks all very much in advance!

The problem is that my dad bought this car as a fun car but he is very poor at keeping it maintained and I think he thought it would be a car that would start up every time with no issues but he's found out that you can't just store it in a garage at your second house and not use it for months on end, and expect it to be fine like any modern car would be.

As you can imagine, it is very frustrating to me to see it sitting there but I haven't mastered the art of driving a manual so I can't do anything about it.

He has disconnected the battery so maybe a new battery is in order as well as a good tune up.

Sorry to say this, but you are in a situation where a knowledgeable professional is necessary, someone who is physically present with the car.

Put every issue aside until you get a Porsche professional to diagnose the loud knock. Don't worry about anything except that knock. If it turns out to be a bad bearing or rod knock, your path is set for you--the engine needs to be torn down and all other running issues will/should be addressed at that time. Continued running the engine with a rod knock will destroy it.

If you want to address issues other than engine related, go ahead, but don't run the engine until you know the cause of the knock.