My Vanagon is acting like the ckoke is on the oil has a lot of gas in it after 50 miles of driving?is it the computer
Asked by PlowBoi Aug 26, 2007 at 07:43 PM about the 1984 Volkswagen Vanagon
Question type: Maintenance & Repair
my Vanagon is getting bad mpg. a lot of oil in the gas andits running decent i just gave it full tune up set timing. and its still doing it?I was thinking maybe a computer issue or vacum lines i dont know much about vanagon could please point me in the right direction.
Thank you for your time
Geoff
7 Answers
Hi PlowBoi, If you're burning oil (oil in the gas) you have more serious problems than you know. This is should be taken into your mechanic. If you have gas in your oil, you will experience serious problems down the road if not taken care of. Gas will "thin out" the oil causing it to break down extremely fast. This will cause your internal engine components to wear at an alarming rate. This should also be taken into your mechanic. Good luck!
Check for corrosion at the engine ground wires, bolted to the firewall near the ignition coil. If there is an insufficient ground, the fuel system will go full rich as you're experiencing.
I think your Vanagon is idling on rich fuel when warmed up.as if it was still cold. My vanagon after warming up was idling still on rich fuel as if it was cold and after while it stopped running.This did not happen all the time.I have changed the sensor II and this still did not solve the problem. Finaly I bypassed temperature sensor II and installed fixed resistor...now my Vanagon runs and the computer does not see temperature changes. Now is running OK.
I'm thinking of buying an 87 Vanagon with the same symptoms. It sat for a long time and I think the groung wires solution might be a good place to look. There is also a vacuum valve for decelleration that the Chiltons manual mentions. I'm looking for advice on this also as I am thinking of buying mine for a pretty low price and it's in good condition other than this problem.
Curious how fuel can get into the engine oil, if this were an older vehicle with a mechanical type fuel pump then i would say that the diaphragm in the pump had split, it is possible you are over-fuelling due to a poorly set up carburettor or if injected the metering head. Does the engine run normally or is it 'missing' or running fast at idle, you may have an air leak causing incorrect sensor readings thus giving incorrect fuel mixture.
When the fuel system is running full rich, it'll wash gas through the piston rings into the crankcase. As I stated above, corroded ground wiring will cause the van to go full rich. Not as complicated a problem as people want to make it- an easy fix.
just had the same problem with a new (rebuilt) AFM with a bad air temp sensor.