help with 79 911 targa

79 911 targa · 10-06-2009, 05:45 PM

hey ppl im new here and to the whole porsche thing....i have 1979 porsche 911 targa that was handed down to me from my old man and its having troubles starting...

the run down.....i got it towed to my house ,parked it in the garage i checked the fuel pump(replaced new along with filter) so its getting fuel to the cis and to the injectors,also i replaced the coil with a msd and the plugs r getting spark..it turns over but just wont fire up

im lost here as i dont really know a hole lot about these motors... so any help would be great...

pete3799 · pete3799's Garage

Check that your plug wires are on correctly.
the dizzy(distributor) turns counter clockwise.
Fuel, spark, and air and she should start.

79 911 targa · 10-06-2009, 06:19 PM

ya a friend of mine sent me a pic of the plug wires to see if they were on right (they are) but still nothing lol i cant figure it out it should be running

Tsunamiboy · Tsunamiboy's Garage

"your old man". I would say he's your "Saintly Father".

LakeCleElum · 10-06-2009, 07:15 PM

Maybe ask your "Old Man" ........ He might know a "HOLE LOT" more??????

osidak · 10-06-2009, 08:02 PM

pull the fuel pump relay out of the trunk fuse box and jumper the pins and see if she cranks

snbush67 · snbush67's Garage

Quote:

Originally Posted by 79 911 targa

ya a friend of mine sent me a pic of the plug wires to see if they were on right (they are) but still nothing lol i cant figure it out it should be running

Check the picture again some cars have a CCW distributor and the plug wires are reversed.

You could have the wrong picture.

bezza911 · 10:55 PM

Check the DME relay, just had a host of issues from mine, first thought was the immoboliser causing no spark, then possibly the fly wheel sensors, but then replaced the DME relay (even though the old one looked good) with a new one, presto, fired up ! 30 euros well spent! Of course, thats if the 79 has a DME relay, oops!

TibetanT · TibetanT's Garage

Yeah, forget about the DME relay...since the 911SC 3.0L doesn't have one.

If you are getting spark (for sure) and you are getting fuel to the injectors then there are only a couple other things to check. Well, okay, there could be a LOT of stuff to check, but basically timing and compression are next on the list. You should have a sticker in the engine compartment, lower right-hand side with the firing order showing (1-6-2-4-3-5).

The distributor turns counterclockwise, so make sure your spark plug wires are connected properly.

Not a whole lot of information from your post, so check the basics.

Some questions that may come from others, and would certainly help with diagnostics are:

Do you have maintenance records?
When was the car last serviced? (ie. valves set, spark plugs new, oil filter changed, fuel filter changed, etc..)
Did the car run great prior to you changing/removing certain parts?
If so, put the old parts back on and see if the car starts up.

I have to agree with the remark above with regard to: "can you call your father and ask him about this?"
Previous owners are a great help when problems crop up, since they know the car better than the new owner does in the early stages of ownership.

Lastly, buy yourself a Bentley Service manual and any other books (Porsche Factory Manual) you can find such as the Haynes Porsche 911SC 1978-1983 book. Our host, sells these publications as well as the 101 Projects book. They will be a big help now and in the future, especially if you plan on keeping the car and working on the car yourself.

Hope this helps.

79 911 targa · 10-07-2009, 03:07 PM

i asked my dad about it and he told me the car was running rich before it was parked so i might have to lean it out a touch to see if it starts but i dont think the cold start is working

Mysterytrain · 10-07-2009, 03:16 PM

The mixture gets tweeked when the car is warmed up. You might want to post your location so that one of the local pelicans can assist.

TibetanT · TibetanT's Garage

Very true! It certainly could be the cold start valve isn't working. Any way for you to test it? Be careful and have a fire extinguisher handy to be safe.

79 911 targa · 10-07-2009, 03:57 PM

im in canada....edmonton,alberta lol ..

OldTee · 04:40 PM

Stop. You can replace suspected parts to the end of your bank account and never find the problem.

Don't grind away with the starter. Two or three cranks is enough. Too much cranking loads the cylinders with raw fuel and could cause the engine to hydraulic lock up.

How I would proceed. Some of this will not be popular but start here:

Get some starting fluid. Do Not spray it into the intake. Instead just let some essence live around the air filter. If it fires it means you have fire and the timing is close.

You need to check your fuel pressures next. Get some help for this. Start by listing your location and find a new friend who can loan you the tool and talk you thru the process. Join PCA.

This will tell you if you have the correct fuel pressure from the pump.

Chances are you have a air leak somewhere.

Remove the air filter and check if you have a pop off valve. Looks like a toilet seat. Check if it is properly seated.

Put one of the black relays where the red one is.

Check the #6 fuse from the back (passenger end) of the fuse block. It should be blue and free of corrosion.

This should get you on the way to a solution.

Keep us posted.

79 911 targa · 10-07-2009, 05:53 PM

i checked all the fuses and cleaned them up...i did a quick test with the fuel(pulled the main fuel line in engine bay,,turned the pump on and filled a 1 liter pop bottle in 6 seconds)...so it should have plenty of fuel but ill pick up a gauge just to be sure..

would it still start if the cold start isn`t working???? how do i check it?

OldTee · 10-08-2009, 04:21 AM

Cold start valves don't fail often.

Check that the wires are on the thermal time switch. lower left chain tensiioner housing.

Has it ever fired?

Check carefully the seam on the air box for a cracks.

79 911 targa · 10-08-2009, 05:16 AM

ya my dad parked it about 5 months age and it hasnt ran sense than till now that im trying to start it,

OldTee · 10-08-2009, 11:08 AM

Has the car ever backfired?

I suspect you have a severe vac leak in the CIS system. If so you can try forever and it won't fire. A Porsche will still run even tho well out of time. It stumbles, farts, snarls but it does run.

I can imagine your frustration. Fixing a CIS is not brain surgery but how is operates or doesn't operate is a mystery to all but the most hardy of us. I am not in that unique group.

Things to think about. It won't fire with wet, or oil fouled plugs. Did you try the starting fluid? What happened. Be careful of that stuff, use sparingly.

Oh, you did put the distributor rotor button back in. You won't be the first if you didn't and won't be the last either.

79 911 targa · 03:39 PM

Quote:

Originally Posted by OldTee

Has the car ever backfired?

I suspect you have a severe vac leak in the CIS system. If so you can try forever and it won't fire. A Porsche will still run even tho well out of time. It stumbles, farts, snarls but it does run.

I can imagine your frustration. Fixing a CIS is not brain surgery but how is operates or doesn't operate is a mystery to all but the most hardy of us. I am not in that unique group.

Things to think about. It won't fire with wet, or oil fouled plugs. Did you try the starting fluid? What happened. Be careful of that stuff, use sparingly.

Oh, you did put the distributor rotor button back in. You won't be the first if you didn't and won't be the last either.

ya it did backfire 2 times from the intake..is that a sign of a air leak???? i tryed the starter fluid and it didnt do anything...
...i just ordered plugs,wires,cap and rotor as they look pretty old and should be replaced anyways..

OldTee · 10-08-2009, 05:12 PM

This is a tough one. If you have a cracked air box or an intake leak you can forget it starting until all leaks are fixed. The backfire was probably a over lean condition due to the lack of vacuum.

A good shop will have a smoke detection machine. It is hooked up to the intake thru the hose port for the power brake (left side of the box forward about 1/2") that shows where the leaks are. You have been fooling with a lot of stuff and all connections must be in the proper place for the system to work. You need to get some help, this system is not like anything you have dealt with in the past.

If it did not run on the starting fluid it means one of two things.

You are not moving a combustible material into the cylinders or you are not getting fire. (low compression too, but even a low compression engine will fire with starting fluid)

Don't give up. When it is all sorted out you will have a ball with it.