1983 Volkswagen Rabbit Fuel or air issue?

Tiny
JETSKI
  • MEMBER
  • 1983 VOLKSWAGEN RABBIT
  • 4 CYL
  • FWD
  • MANUAL
  • 15,000 MILES
I have a 83 rabbit convertable 1.7 with 150,000 miles. It takes a long time to start and idle. It will crank and start, idle for a few seconds then stall. The more I start it. The better it gets. After about 10 to 15 times starting it, it will stay running, but when you step on the gas it stalls. When it gets hot it runs pretty good but, skips when you accelerate. I've replaced the cold idle valve, frame mount fuel pump, plugs, wires, cap, rotor and fuel filter. Now the strange thing I found when I press on the rubber boot air intake tube between the fuel deliver system and intake the car stalls. I am not sure now if it's an air issue or fuel issue Can you help. Thanks
Wednesday, February 18th, 2009 AT 6:31 AM

10 Replies

Tiny
RACEFAN966
  • MECHANIC
  • 5,029 POSTS
Ok does the air intake boot have any cracks or splits in it? Can you include a pic of the hose you are refuring to so I make sure we are thinking on the same page? Thanks and get back to me.
Was this
answer
helpful?
Yes
No
Wednesday, February 18th, 2009 AT 10:24 AM
Tiny
JETSKI
  • MEMBER
  • 6 POSTS
It's actually when I put pressure on the air intake rubber boots, the one at the air filter box and the one next to throttle body. I can press on them with one finger push them in about 1/8 to 1/4 inch and the car stalls. Seem like the car is starving for something when I try and start it.
Was this
answer
helpful?
Yes
No
Wednesday, February 18th, 2009 AT 1:47 PM
Tiny
JETSKI
  • MEMBER
  • 6 POSTS
Forgot to mention that I did the leak check through out whole engine. It does not stumble. Even checked intake manifold gasket for leaks. I also did air box valve test, it moves freely, cleaned it anyway. Also replace lots of vacumn lines with new ones. Also did pressure test on fuel line, it's fine. Gone to two garages, charged a fortune for diagnostics and can't find what's wrong. I've been working on it for months on and off. This car will be the death of me.
Was this
answer
helpful?
Yes
No
Wednesday, February 18th, 2009 AT 2:01 PM
Tiny
RACEFAN966
  • MECHANIC
  • 5,029 POSTS
Ok if you can push on the intake hose and the car dies then there should be a crack in that boot. See when you push on it the crack opens and the car can't read the amount of air coming in so it dies. If need be take the intake hose off and look it over really good for any places of weakness or cracks and let me know what you find.
Was this
answer
helpful?
Yes
No
Thursday, February 19th, 2009 AT 10:41 AM
Tiny
JETSKI
  • MEMBER
  • 6 POSTS
Went through whole air duct no cracks anywhere. Also tested thermo time switch and new cold start injector, just in case. Also checked the airbox valve it also seems to work fine. No luck, still starts then stalls when cold. When it does start and I step on the gas it stalls out. If I let it warm up to the point the radiator fan kicks on it seems to run ok, except when I try to accelerate it skips a litte bit. Don't know what else to do. Could it be something simple and stupid like a relay? Pulling my hair out.
What is testing the duty cycle?
Was this
answer
helpful?
Yes
No
Friday, February 20th, 2009 AT 6:49 AM
Tiny
RACEFAN966
  • MECHANIC
  • 5,029 POSTS
Ok you need to test the coolant temp sensor. If you have a digital multi meter then you will need to unplug the sensor and do an ohms test of the sensor itself and get back to me with the ohms and temp of the sensor at the time of test if it is cold then ambient air temp will do just fine.
Was this
answer
helpful?
Yes
No
Friday, February 20th, 2009 AT 10:12 AM
Tiny
JETSKI
  • MEMBER
  • 6 POSTS
I replaced the temp sensor with a new one only 11 bucks. It still does the same thing starts idles around 1000 rpms for a couple of seconds then stalls.
Was this
answer
helpful?
Yes
No
Monday, March 2nd, 2009 AT 6:46 AM
Tiny
RACEFAN966
  • MECHANIC
  • 5,029 POSTS
Have you checked the fuel pressure itself? If not see if you can rent a fuel pressure tester and test the fuel pressure as we need to know what it is. Get back to me.
Was this
answer
helpful?
Yes
No
Monday, March 2nd, 2009 AT 6:52 PM
Tiny
JETSKI
  • MEMBER
  • 6 POSTS
Fuel pressure is 80psi steady, also changed fuel filter.
Was this
answer
helpful?
Yes
No
Tuesday, March 3rd, 2009 AT 7:24 PM
Tiny
RACEFAN966
  • MECHANIC
  • 5,029 POSTS
Ok the fuel pressure is a couple of pounds high but I con't think it is a problem. I would like you to check the air flow sensor for proper operation and alignment. I have included a pic to help.
1) Remove the rubber bellows boot to expose the sensor plate and disconnect the electrical connector from the auxilary air valve and control pressure regulator. Turn the key on engine off for about 10 seconds to build up fuel pressure.
2) Now very carefully lift the sensor plate with a magnet or pliers. While you lift it there should be constant pressure felt. Slowly lower plate and it should level.
3) Now lift plate and let it drop into position. You should hear it you should hear it hit the lever if not it is sticking. If it is sticking then remove it and clean with carb and injector cleaner and see if it works as it should. Get back to me with what you find.


https://www.2carpros.com/forum/automotive_pictures/249564_Graphic_46.jpg

Was this
answer
helpful?
Yes
No
Wednesday, March 4th, 2009 AT 10:44 AM

Please login or register to post a reply.

Related Air Intake Tube Boot Content