My 87 vanagon will not pass smog. It lopes at an idle, hesitates badly during driving and blows black smoke. It does not do this all of the time, it has progressivly gotten worse over the last couple of months. I looked the problem up in a book and it told me to: reset vacuum kick reset fast idle cam index reset fast idle rpm The book however did not tell me where these things are located or how I can fix them. Please help!

Dear cc_racer- There is only so much we can do in "do-it-yourself" mode. You need a professional mechanic to look at your 1987 Volkswagen Vanagon. Without proper repairs, which might not be cheap, your car will not pass inspection anywhere and it will continue to be a major contributor to air pollution. Good luck from Bovan.

How did you solve this problem? We have had the same problem (with the added complication of being intermittent and being temporarily solved by turning off the engine and restarting). The two local VW mechanics have been unable to solve it. I suspect a faulty sensor signal to the ECU... have already replaced O2 sensor and fully cleaned air flow sensor. Replacing ECU did not help. Please help.

Did you solve your problem? We have the same problem and no one is able to fix it. Please let me know, thank you

Looks like it's fuel related problems. Check and see if your fuel pump is working properly, if it's dying out, fuel will not be delivered to the engine properly, this will result in lean buring mixture(black smoke); the next thing to check will be the fuel pressure regulator, if it's faulty, fule will be dumped into the engine uncontroled, in this case, it will result in rich mixture(also black smoke); check you fuel injector to see if it's cloged; Other things you might want to check in the fuel system are: fuel lines, spark plugs, and the fuel return line. Hope it helps, good luck

Thank you for your reply. I will check the fuel pump and pressure regulator. What is happening is: When we start in the morning, it will run smooth for an hour or so, then start acting up. The solution is to turn it off and on, then it runs properly for few minutes and act up again. At that point, it will run rich, and run 8 or 9 miles per gallons. When it is running smooth, it will get between 15 to 20 miles per gallon.

Where you able to solve this problem? Could you share with me how you fixed it? Thank you

You are describing an air fuel ratio malfunction. You are burning too rich but only at certain times. Based upon the info provided, I'd say your automatic choke is malfunctioning. When first starting the vehicle, press the gas to the floor ONCE then release, this sets the automatic choke. The fuel mixture is richer when the engine is cold to facilitate a quick idle and faster warm up; also, it allows the engine to run without dying when it's cold. When the engine gets warmer, heat from the exhaust manifold radiates through a metallic hose to the throttle body via the intake manifold. The warm air cancels the automatic choke and the fuel mixture changes from rich to lean. The engine runs normal at this point. I think your engine can't tell when it's not warmed up. This can be created by the metallic heat transfer hose being damaged or missing. Also, if it starts to cut out on you and it's already warmed up, try revving the engine just a single time, that usually resets it. Investigate this route before you start digging into more expensive repairs.

logan you seem to kow a bit about these issues, i just bought a 85 vanagon, this guy has replace about everything on it and built it up to a 2,6 water cooled, fuel injected, in cal tried to drive it to texas it broke down constantly, i have replace fuel pump twice, replaced computer, had it in shop etc etc, it seems that mechanics are pretty clueless about this type van, i keep replaceing the same stuff over and over, i am haveing the same issues as above, runs sometime than quits, blows black smoke i can hear fuel pump reveing up etc, is this type van repairable? im afriad to take the kids anywhere but the corner store,,trying to buy a repair manual but they all seem to be for air cooled,,any advice would be greatfuly appreciated thanks jack,,,,,jbigelow70@att.net

Check the ground strap running from the left side of the engine compartment to the engine block. Poor ground causes fuel injection to run at full rich. If this doesnt repair the problem, there is a transformer which plugs in between the harness and the mass air flow sensor which addressed this issue. There was a VW Technical Service bulletin on this many years ago.

I was reading all of your replies and I happened to come across this problem on a Vanogan. Weird as it seems it turned out to be the fuel injectors. Customer came in with the same complaint. Runs great for 5 Mins and then looses ppower, black smoke and poor fuel mileage. After extensive testing I found that the fuel injectors when cold ohm test out @ 16.0 ohms for an average. After warm up and problem arrives, the resistance would hit 108 ohms. Even though it was emitting black smoke, the van ran better when the return line was pinched off causing fuel pressure to spike from 35 psi to 90 psi. This is due to injector pintle opening amount was limited when warm that directly effected the spary pattern and its ability to atomize the fuel properly. If this helped you in anyway, please look my shop up on Facebook and hit the like button. Escondido German Auto . Thanks and good luck.

I also forgot to mention to Unplug the O2 sensor as it will try to increase injector pulse width due to the amount of Oxygen in the exhaust from the poor burn. Thanks and good luck.

Wow, this is obviously a common problem with the VW Vanagon. We purchased ours this month and have put in as much for repairs as we paid for the vehicle. Many "age related maintenence" problems we're solved, but NOT this one...which is pretty serious when driving on a public roadway - particularly the freeway! We were hopeful that it was "better" but 50 miles on the way to home the it cut out and dropped from 70 mph to 40-45mph. We babied it the rest of the way home, and after it sits for a while...it appears fine again...until it gets warmed up! So, we are definitely taking these suggestions to our repair facility (which is a VW dealership) and have them read it and see if they can "fix" this problem so we can actually feel safe taking it somewhere other than our very small town! Thanks very much for the help. We'll let you know if we are successful!

Wow, this is obviously a common problem with the VW Vanagon. We purchased ours this month and have put in as much for repairs as we paid for the vehicle. Many "age related maintenence" problems we're solved, but NOT this one...which is pretty serious when driving on a public roadway - particularly the freeway! We were hopeful that it was "better" but 50 miles on the way to home the it cut out and dropped from 70 mph to 40-45mph. We babied it the rest of the way home, and after it sits for a while...it appears fine again...until it gets warmed up! So, we are definitely taking these suggestions to our repair facility (which is a VW dealership) and have them read it and see if they can "fix" this problem so we can actually feel safe taking it somewhere other than our very small town! Thanks very much for the help. We'll let you know if we are successful!

Goto volkswagon website and you will see all the recalls for year and models. Some previous owners may have fixed these problems or not. Hope that helps.

replace the ends of all ground wires on engine with new ones and on the ECU under back seat # 19 is a ground again cut end of wire off and replace with new wire end to be screwed down to ground and behind passenger side rear tail lite is the idle control change this out and it is not cheap.

catalytic converter possibly failing try disconnecting wires coming from exhaust pipe chances are 20 year old veh do not need emissions chk

I do not know whether yours has a cold start valve. An over active colld start valve will give the same problems. Enrik