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Sun Jul 14, 2019 9:50 pm

I just recently acquired a 1974 914, 2.0 from Florida. I live in Utah, 6000 ft. above sea level where it previously was. Once the car warms up it likes to stall out at any stop or slow down below 5 mph, and it idols around 200-300 rpms. I think it may be running rich, but if it is I'm not sure what adjustments I can make because it's a throttle body, mechanical fuel injected. Any thoughts on what to do with it?

Many Thanks!

Mon Jul 15, 2019 7:58 am

So......you say its "throttle body" injected? Meaning the fuel injector(s) are up in the throttle body like a lot of 1980s American cars?

And its "mechanical" injection?.....meaning like Bosch CIS injection?
So does it have an air metering plate system like CIS?
Is it using the original fuel injection intake manifolds (4 seperate runners and a plenum in the middle)?

If all of this is true.....first...VW/porsche engines with individual intake runners....are terrible with throttle body injection. They are even worse than using a centralized carburetor on this intake set up. They are bad enough with the carb because the runners are long and there is no manifold heat.
TB injection is worse in this set up because along with no manifold heat.....you have the fact that injectors do not atomize fuel. It produces micro droplets that are swept into a port while suspended in airflow (in a perfect world).....in a long runner style intake tract with no heat.....injected fuel quickly becomes liquid running along the intake walls.

Take a few pictures and post. We need to know what components your system has yo help at all. Ray

Mon Jul 15, 2019 8:48 am

It should be a Bosch D Jetronic, I do fault finding on 914s for an official BOSCH agent down in france D and L's. If its an original D jetronic don't remove it or you will take 20% off the value.
What you need to do is to remove the vacum line from the MPS put a clean hose on it and try and blow down it if you can blow down it or suck air through it the MPS diaphram has got a hole in it and it is your culprit. Start from there and get back to me.

Mon Jul 15, 2019 9:09 am

there could be several problems: I would start by making sure that the compression is even, the valves are in adjustment the dwell and timing are dead on the money, and the hot idle and idle enrichment are set. After that check the hot fuel pressure, the pressure sensor and the head temp sensor resistance

todd.michael3325 wrote: I just recently acquired a 1974 914, 2.0 from Florida. I live in Utah, 6000 ft. above sea level where it previously was. Once the car warms up it likes to stall out at any stop or slow down below 5 mph, and it idols around 200-300 rpms. I think it may be running rich, but if it is I'm not sure what adjustments I can make because it's a throttle body, mechanical fuel injected. Any thoughts on what to do with it?

Many Thanks!