QuestionRon,
My son has a 1977 VW transporter with the Bosch Fuel Injection. My mechanic tells me that the fuel injection computer is faulty and causing it to run very lean and hot. There is a very low power from the engine. It is a recent rebuild with hydraulic lifters and cam. I have not been able to verify this diagnosis or able to find a replacement fuel injection computer, these seem to be very difficult to find. I would think there must be someone who repairs theses units. Any help greatly appreciated.
Best,
Jeff
AnswerJeff,
I have been working with these systems for years, and I can say with a great deal of confidence, that it is very rare that the computer would be shot, causing such a condition that you describe.
For the fuel injection system to create such a 'lean' condition that it would run very hot, yet with no power -- I would check the following first:
1)#3 Cylinder Head Temp Sensor: This is a screw-on type part that costs under $20.00. You can check this part out with a simple voltage meter, refer to the Bentley Manual for proper settings.
2# There is an air leak somewhere. This is the 2nd most common problem with creating a lean condition on that engine. The motor is a variable maze of vacuum lines, hoses, connectors, etc. Each one needs to be checked for 1) accuracy of hook up #i.e. does it belong here# and 2) loosness, dried out, or broken/missing hose.
3) Ignition timing is not correctly set.
4) Hydraulic valves are not properly adjusted. #although they require no adjustment as a rule, they need to be adjusted upon rebuild#. See Bentley manual.
5) The intake air sensor flap is getting stuck. Again, you can test this part with a simple voltage meter and the Bentley manual.
6) There is a kink / clog in the fuel line somewhere.
The fuel injection system is very hearty. I would eliminate everything else in and around the engine prior to being suspect of the components.
Best of luck, and please keep me posted.
Thanks,
Ron
