Shop w CIS experience in the O.C.
 

This forum has been great w tech advice. I think I'm coming to a point where I'd like to find a shop to finish up trouble shooting my 73.5 CIS 911. I'm asking for someone close to Irvine that can perform the pressure tests to my car to locate the problem. This could become a novel but I'll try and keep it short. ( already it's too long)
All stock CIS running great. Past year starts to cut out at upper RPM. So I start chasing the problem. "while you're in there" and " one thing leads to another" has me at this point.
All fuel lines replaced along with fuel pump and check valve.Tank drained and checked visually.
Fuel infectors cleaned, back flushed, spray pattern tested in jars, new seals.
New plugs, wires, points, cap and rotor.
Timing at 5 degrees ATDC, advances with RPM.
Carb cleaner sprayed to try and find vacuum leaks.
During all of this, the car got to a point where it barely would run so it started the process. After all this, it's hard starting, barely idles, hunts when it does, pops and misses but... I can drive her around a couple of blocks. I'm at the point where I can buy the CIS pressure guage and continue or find a shop... Oh! I pulled the plugs and they are all black from too rich a mixture, I replaced with a clean set and it helped but only a little. I thought I'd put this out there because you guys have helped me all to this point and you suggestions are greatly appreciated. I've been reading and searching up to this point. I want to drive my car!!!!
Thanx guys!

Randy at Porshaw - Porsche Parts and Service - Orange County, CA

Aux. Air device
 

One other thing is that I found the hose from the auxiliary air device unplugged before and when I hooked it back up, the car didn't run as well so I left it off. It is vacuum operated, I tried plugging it in again and it made the current running condition worse. Just FYI in case some says, " I know what the problem is, it's......... "
Thanks,

Bill Brewster Porsche service in San Clemente.

Factory trained and over thirty years experience. Honest and straight forward. Only problem, he's usually very busy so be aware it may be a while before he can deal with your issues.

Regardless of what you decide to do now, if you're planning on keeping a CIS car you should invest in a pressure gauge set as it's a basic tool for any diagnoses.

BTW, what do you mean by the "auxiliary air device?" Do you mean the decel valve? 73.5 doesn't have an auxiliary air valve or regulator.

+1 for randy shaw i drive from the IE for him to work on my car.

Dwain at Vision Motorsports in Laguna Hills.

Auxiliary air valve
 

It's also called a Decel valve or vacuum limiter? It's funny how it has a vacuum line and when I hook it up to the valve, the car runs worse even though it's stopping the vacuum leak!

try adjusting your CO as that sounds like your issue. I had a similar issue. Check the board for adjusting the CO very easy

CO adjustment
 

I'll give the CO adjust a quick try. I can always go back to where it's at. If it seems to be working, I'll research more and try to do it the right way!
Thanks,

Basic troubleshooting.........
 

Randy,

A fuel pressure gauge kit is mandatory for fuel injection troubleshooting regardless of what system you have. Without one, you'll be doing a lot of guesswork or assumption. Check the fuel pressures (control and system). And lastly, verify the absence of a significant vacuum/air leak in the system. Pressurize the system with low gas pressure (2 - 3 psi). Carb cleaner or starting fluid is not as effective as pressurized gas in locating hard to find leak/s. Keep us posted.

Tony

I guess I'll have to get on it this weekend. If I pressurize the system, where should I do it at and... I read that smoke would be a good indicator visually. Any other means of finding the leak, besides listening,feeling, etc.?
Thanks,

Visual aid......
 

Randy,

Don't make it too complicated. How do you think they locate radiator or tire leaks? It is either leaking or not so choose a method that you could apply as DIY'er or bring the car to shop that has a smoke machine. This is an example of what you might find if you have an air leak in your engine or around the air box.

http://forums.pelicanparts.com/uploa...1335440784.jpg

http://forums.pelicanparts.com/uploa...1335440808.jpg

Notice how low the air pressure that was applied? A battery operated tire pump or air compressor would be a good choice to deliver the needed air into the system. Keep us posted.

Tony

Yep! That's simple enough. Will give it a try.
Thanks,