HOW many CORRECTLY running cars are there really?

[ant7]

My 3.2 starts pretty much straight up, cold, or hot, and idles ok,[it wasnt always the case] although the one thing that has always concerned me a bit is; the idle doesent seem to change when i remove the oil filler cap, i have checked for air leaks etc, but havent found anything obvious yet, apart from that, it seems to drive fine.
A...

[Bob Kontak]

its all too confusing..............

There are four things designed to allow air to bypass the throttle. Two are used on start up. One is used when you lift off the throttle at high rpm. One is the idle air bypass screw. That is not overwhelming one piece at a time.

There are no other places air should enter your intake except for the throttle and when you pull the oil cap off.

[Bob Kontak]

Originally Posted by ant7

My 3.2 starts pretty much straight up, cold, or hot, and idles ok,[it wasnt always the case] although the one thing that has always concerned me a bit is; the idle doesent seem to change when i remove the oil filler cap, i have checked for air leaks etc, but havent found anything obvious yet, apart from that, it seems to drive fine.
A...

Idle will not drop on a 3.2 like the SC. Your fuel delivery is not based on intake vacuum which lifts an air sensor which changes the injector fuel amount. Pull the cap on an SC, you change the vacuum and the air sensor moves.

[CCM911]

I just had Ingo Schmitz repair my ECU. It is a 1984 3.2 Targa. In March, I drove it from Philadelphia to Amelia Island and back. I beat the living daylights out of it there and back. My voltage regulator failed within the first hour. I kept driving. Nothing happened. I made it to Florida with no drama. Just an oil leak that, while not causing dramatic oil loss, did manage to spray a nice film of oil all over the rear of my car. Got the car home. Spent $80 and replaced the voltage regulator. Got the oil leak almost solved.

My car runs probably better than it did when it left the factory. And yes, every year when I take it in for the State Inspection, my tech takes it for a drive. He claims it runs perfect.

If only the damn thing would stop leaking on me!

[tmaull]

I'm not sure how many correctly running cars there are out there, but mine ain't one of them. Working on it though.

[SilverWT]

Originally Posted by Bob Kontak

Idle will not drop on a 3.2 like the SC.

The idle should drop on a 3.2 when you remove the oil filler cap, as you introduce an air leak through the oil breather pipe.

There is even a restrictor in the oil tank breather pipe to make sure it does not drop too much so you can check the oil level OK, without the restrictor the engine stalls when you remove the oil cap.

Mark

[911SauCy]

mine starts, idles st 900, and pulls like a mother to redline and idle drops with cap removal.
well, that was before it dropped a valve guide

[Bob Kontak]

Originally Posted by SilverWT

The idle should drop on a 3.2 when you remove the oil filler cap, as you introduce an air leak through the oil breather pipe.

There is even a restrictor in the oil tank breather pipe to make sure it does not drop too much so you can check the oil level OK, without the restrictor the engine stalls when you remove the oil cap.

Mark

I looked up the oil lines and parts for 84-86 and saw the restrictor.

Thanks for the info. I know that early CIS cars don't have the idle drop because of plumbing.

[Superman]

I recently got my car back from John Walker's Workshop, and it's ready for LeMans.

[kent olsen]

Well I guess that's why I stuck with my Weber's on a 3.0L in my 72. Ignition/carberation, that's the only thing you need to look at.

[seanratpel]

yep. the idle used to drop before I put new studs in, now with new O-rings, vacuum hoses and the like it stalls immediately. frustrating to say the least

[ant7]

Yep,
Thats what I thought, and I changed the breather pipes as soon as I had the car, I put the restrictor back in too, as stated, still not sure why the idle doesent drop when the oil cap is removed.

Originally Posted by SilverWT

The idle should drop on a 3.2 when you remove the oil filler cap, as you introduce an air leak through the oil breather pipe.

There is even a restrictor in the oil tank breather pipe to make sure it does not drop too much so you can check the oil level OK, without the restrictor the engine stalls when you remove the oil cap.

Mark

[deguitars]

I bought my '82 SC a few years ago and it ran like crap. Mechanic said it was the WUR so that was rebuilt. It ran better after that but for the next year or so it always seemed to start differently each time...basically some variation on the theme of fires immediately from cold then stumbles, pops, spits and finally settles into a 1200 or so idle when cold. Hot starting was sometimes a real issues too but not always. Replaced the usual: plugs, wires, set timing, new fuel filter, new accumulator, etc. and no real change. Always had a strange hiccup in the idle once and again. If anything it got worse the more parts I changed.

So finally I decided to take a look at the injectors which is something nobody really seems to talk much about when discussing CIS. After considering the pro's and con's of how much work is required to simply pull and clean them I decided to just install new parts. So I pulled and replaced all six injectors and sleeves with new o-rings everywhere. Starting is transformed. Fires immediately and settles right into a nice idle dead cold after sitting for weeks. Same thing hot.

So my two cents is don't overlook an important link in the chain when diagnosing starting issues.

cheers

[Dodge Man]

I have been thru both MFI & CIS on the same car. You may have to take a step back and think like the engineers that designed the fuel systems. MFI is a "hoot" to say the least but "warm up" is not for the "plug & play" crowd. CIS was easier on the driver but remember that Bosch CIS was probably the most widely used OEM FI in the world for about 20 years on numerous makes & models but it is not EFI. Then came EFI to make things more "plug & play". FI works how it was designed & operates within tolerances unless there is a real problem so I tend to put things in that perspective. CIS in a 40 year old P car will require some care & patience/tolerance. Having passengers complain about warm up running of MFI on a cold day is just standard operating procedure in this overly PC world. I just ride with Speed Dog to avoid stupid comments/complaints and then I have a very pleasant ride.

[tirwin]

Originally Posted by deguitars

I bought my '82 SC a few years ago and it ran like crap. Mechanic said it was the WUR so that was rebuilt. It ran better after that but for the next year or so it always seemed to start differently each time...basically some variation on the theme of fires immediately from cold then stumbles, pops, spits and finally settles into a 1200 or so idle when cold. Hot starting was sometimes a real issues too but not always. Replaced the usual: plugs, wires, set timing, new fuel filter, new accumulator, etc. and no real change. Always had a strange hiccup in the idle once and again. If anything it got worse the more parts I changed.

So finally I decided to take a look at the injectors which is something nobody really seems to talk much about when discussing CIS. After considering the pro's and con's of how much work is required to simply pull and clean them I decided to just install new parts. So I pulled and replaced all six injectors and sleeves with new o-rings everywhere. Starting is transformed. Fires immediately and settles right into a nice idle dead cold after sitting for weeks. Same thing hot.

So my two cents is don't overlook an important link in the chain when diagnosing starting issues.

cheers

I'm sorry to say but injectors, o-rings and sleeves are things that are frequently discussed. Tony (boyt911sc) often recommends that people pull their injectors and stick them in baby food jars to check the volume of flow and spray pattern. The o-rings and sleeves are well known vac leak sources.

Not trying to be a jerk here. I'm just pointing out you ran into one of the many problems with Internet troubleshooting. If I could wave a magic wand and have any of the resident CIS experts standing in my driveway swilling a beer while we looked at a problem, we probably could get to the root cause a lot faster. Looking at something in person is so much better than trying to ask "does it go ca-chunka ca-chunka or more of a ping thwap wap?" on an Internet forum.

And maybe when you posted the guy who might've correctly diagnosed the problem in a flash was out on vacation that week.

All that being said, I'm sure glad you found your problem and got it sorted out.

Bringing that full circle back to the original post... it is hard to say that a car runs like it should when you have no basis for comparison. Hard to hit a target if you don't know what you're aiming for. I was 10 when my car rolled off the assembly line. I grew up in BFE Alabama. I could tell you what a '83 Camaro should sound like but not an '83 Porsche 911. In fact, the only thing I did know was that my car sounded a lot more like an old Camaro when I bought it and that ain't right!

PS - My wife says it's easy to know what an old Porsche sounds like. A Volkswagen! Gets me fired up every time.

[Alex973]

I was told by my wrench your car will die on a Tuesday, he does not tell me which Tuesday
it has been 9 years since a transplant done, she just keep on running, love this 911 thanks

[deguitars]

Take it easy Tim. I'm not sure what "problem" you think I ran into.

My car ran better with a new WUR but still had the cold start stumbles. So I worked my way through a list of long deferred items and then made a judgement call to deal with the injectors since they were original as well. I see probably 10-15 posts about WURs to every mention of injectors and was just passing along my experience for others so consider what you paid for the information...

cheers

[tirwin]

Originally Posted by deguitars

Take it easy Tim. I'm not sure what "problem" you think I ran into.

My car ran better with a new WUR but still had the cold start stumbles. So I worked my way through a list of long deferred items and then made a judgement call to deal with the injectors since they were original as well. I see probably 10-15 posts about WURs to every mention of injectors and was just passing along my experience for others so consider what you paid for the information...

cheers

Sorry didn't mean anything by the comment. I did try to preface what I was saying. Apologies if it came across the wrong way. I get your point now.

My point is, kinda like you said, you read 10 posts where people have a problem with the WUR and then 1 on the injectors. Easy to fixate on the WUR when that might not be your problem. I've done it and probably most of us have done the same thing at some point. You formulate a list of possible culprits and then you start trying to track them down and rule them out until you find the problem. If you're good or lucky it's the first thing on the list. If not it's the 10th thing on the list. But if you started with checking the fuel pressures and found no problem, for example, that's not necessarily time wasted. It means you know with confidence that is not the problem and that is still valuable info. It seems like a lot of CIS issues are not one thing but a combination of things (like the classic mixture enrichment to cover up vac leaks). While it may take longer and be frustrating that the 10th thing on the list is what really fixed it for good, that is how you make sure the car is running correctly, which was the original question.

[Bob Gruen]

My 87 Carrera was sold to the first owner in Sarasota. It never idled right, and the local techs just richened (sp?) up the low end fuel and let it stumble. Back then the Porsche mechanics in Sarasota were not 100% full time Porsche mechanics, I am assuming they probably are today.

I bought it off of the Doc years later and took it to Black Forest Automotive for it's 60K 'turn your head and cough'. I told the tech about the idle when I dropped it off and he immediately wedged his head into the engine compartment and said "Yup. You are missing intake manifold gaskets." Wha? When I picked it up he told me that they had seen Carreras that had missing gaskets and gaskets that had 'sucked in'. Mine had both, big time air leak. Idled fine after that.

My takeaway from this is if you have access to (and can afford to) take your car to a race shop for any real problems you can't handle or figure out yourself. They are the guys that really know these cars. So far I have managed to do all of my maintenance and repairs myself, including a clutch replacement, but I am dreading the big engine problem that requires a true pro to fix.

Bob