HELP! have to let the car warmup???

[gterry]

hi guys im new on here and new to porsches i just bought an 82 911 sc. but when i get in and start it i have to let it warm up for 5-7 minutes before i go anywhere? is this normal? if i get in start it and touch the gas it cuts out or just dies the rpm drops so low. it does have a cat delete/test pipe and a small 20inch muffler so could my problem be as simple as not enough back pressure? if so how much would it cost me (ballpark) to get a stock cat and muffler? any help will be GREATLY appreciatted!!!

thanks!
greg

[MotoSook]

You need a CIS tuneup.

Did this just start happening?

[gterry]

[QUOTE]You need a CIS tuneup.



Did this just start happening?[/QUOTE

Na its been like this sense i bought it like a week ago! What is a cis tuneup? Can i do that or will i have to pay somebody to do it?

[Gunter]

Buy the Bentley SC Repair Manual and read and study.

Could be many different reasons why it cuts out but normally one just starts and drives.

When was the last major tune-up done?
Like valve adjust, cap/rotor, plugs, mixture adjusted?

Who services your SC?

[DRACO A5OG]

Greg, it sounds like there is a vacuum leak, when warm the hose or component expands creating less of a leak.

When warm, remove the oil cap to see if the idle drops, if she doesn't you have a vacuum leak. check each fitment and hose for tears. Spray some ether ( starter fluid around the intake manifold, hoses fitments, etc..., But insure there are no errand sparks by checking in the dark with mist of water from a sprayer)

OUR 911's do not need to be warmed up, especially for 5-7 minutes you must drive off immediately to help ciculate the oil in the engine.

Jim

[Laneco]

+1 - on the vacuum leak as likely suspect. Missing restrictor could also do this (same idea, just not the first thing you think of).

angela

[gterry]

Im not sure when the last tuneup was done i bought it off a lot and the dealer told me it had all the maintenece done regularly (highly doubt that but thats what i was told)

I have been told by a few people its a vaccuum leak ive done a few quick looks so i'll look into it more and definatly try out the oil cap thing.

Thanks for the help guys!

[DRACO A5OG]

Roger That, keep us updated and post some pics of your baby

[gterry]

Sorry it took so long to reply guys, work has been crazy. I checked all the vacuum lines and did replace one but the rest seem fine. When i take the oil cap off when its warm the idle does drop but just very slightly. Is that normal? Any ideas? I will post pics ASAP my computer is on its last leg it cant handle uploads haha

[saxen]

Sub"d

[Gunter]

Yes, it's normal to drop RPM a little with cap off.

Without knowing more about the general condition of components and maintenance history, it could be many things and at this point it's just guessing.

You'll need a tune-up by an experienced 911 mechanic for an accurate assessment.
An '82 has lots of CIS components for cold-start and each one can be checked individually by someone who knows. The CIS is more complicated than you think; get the Bentley and study.

A good tune-up will give you a base-line with new plugs, cap, rotor, ignition timing and mixture set correctly.

Guessing from a distance isn't going to do it.

[Gunter]

Bill,

PCV valve? Hard line?
AFAIK, there is no Positive Crankcase Ventilation Valve or hard line.
Instead, there is a hose going from the breather cap to the oil filler neck.
That hose might contain a restrictor but even if the hose leaks, it shouldn't affect mixture.

[Staylo]

Sounds like a WUR issue. Agree on CIS tune-up by a pro.

[gterry]

Alright so i was looking really close for a vacuum leak and found 2 wires that arent connected to anything? One is red with a white stripe and the other is orange? I traced them back and they go to the same harness the wur wires come out off. Could this be my problem?

[DRACO A5OG]

Probably. try and reconnect and see what happens.

[DRACO A5OG]

Originally Posted by bkreigsr

sorry - just throwing out a few places where I found leaks when I got my 85 running. Bill K

PCV valve and hard line on a motronic motor \/

Is there a PVC under that hose?

[Gunter]

Originally Posted by Gunter

Without knowing more about the general condition of components and maintenance history, it could be many things and at this point it's just guessing.

You'll need a tune-up by an experienced 911 mechanic for an accurate assessment.
An '82 has lots of CIS components for cold-start and each one can be checked individually by someone who knows. The CIS is more complicated than you think; get the Bentley and study.

A good tune-up will give you a base-line with new plugs, cap, rotor, ignition timing and mixture set correctly.

Guessing from a distance isn't going to do it.

Bill (nice engine) and Draco:

Apples and Oranges.

He has an SC with Bosch K-Jetronic, not a Carrera with DME which is totally different.

gterry:

Inviting people to do more guessing isn't going to help. We have no idea about the general condition or maintenance of your engine. You need one basic tune-up by an expert to establish a base-line. I mean expert and not the neighbor's son or a corner gas station attendant.

Do it right.

[bkreigsr]

unsubscribed
when people start quoting themselves - time to go

[tirwin]

Gterry,

Welcome! Post pics as soon as you can. First it helps when you're talking about your car for us to get a visual feel and second we love to see 'em.

I have an '83 that I bought earlier this year and found myself in much the same situation as you.

As several people have said, it could be several things. DO NOT just start swapping parts. Our cars have a type of CIS (Continuous Injection System) fuel injection called K-Jetronic that was originally made by Bosch. At this point, you need to ask yourself if you want to work on the car yourself or if you want to have a PROFESSIONAL work on it. If you're not going to do it I emphasized the word professional not because there is any black magic (you can do it yourself) but because you will likely get a bum steer by someone who doesn't know what they're doing which will end up costing you money. If this is not a daily driver, that can also make a big difference in your decision.

If you add your location to your profile you might find 2 things: (1) some Pelican might be willing to come over a take a look at what you've got and (2) you might want to ask for a reference to a reputable local shop.

If you are handy and you are willing to work on it yourself get yourself a copy of the Bentley manual, Wayne's "101 Projects for your 911" book and a book on the Bosch CIS system. I can't remember the author's name of the last one. PM me and I can look it up if you're interested. I won't be home for a few days though.

On to your issue... Could be a vac leak, could be a CIS component, or something else. Search on this forum for "Troubleshooting CIS" and you can read my own history and how I learned A LOT from this forum. There are several threads that cover CIS. Read as much as you can before jumping into action. Ask questions. Lord knows I've asked some dumb ones. That's how we learn.

Agree that a tune-up is a good place to start. My problem mostly went away after I did the tune-up. I'm taking mine to a shop next week for a smoke test because I still suspect I have a vac leak somewhere.

Best of luck to you! Keep us posted on what happens.

-T

[Gunter]

+1

Thank you - T - very good advise.

Some folks mean well but it doesn't help to compare a Motronic system with CIS and create more confusion.

Confucius: "No advise is better than bad advise"