Tuning and Testing

What a cool car to work on.  I think I’m on track with getting it tuned.

I scored an EFI pressure tester today at Harbor Freight this morning.  The kit has all kinds of hookups for different makes, but I found the inline fitting and a spare length of hose to work great when spliced into the cold start tap.  Once I got it clamped up and running, the gage read 34 psi, way too high.  I got the regulator adjusted down to about 29 psi, and the idle speed dropped to around 900 rpm (right where it’s supposed to be).  After running it up to temp, I took it out and tested the decel and idle backfiring.  It still pops every now and then, but it’s nearly eliminated.  Also, leaning it up seems to have resulted in more horsey s  and less busking at mid throttle.  All in all, a big improvement.

I also tested the cold start temp sensor, and it was open at temp.  I’ll have to check in the morning to see if it’s closed when cold.  I’m fairly sure the cold start system is working nominally, since it starts fine when cold, and now apparently runs better at the proper fuel pressure.  I’m still going to test the MFC vacuum sensor and the decel valve, just to make sure everything is cool.

I’ve found some very interesting pages on the 914, and related pages in regards to Bosch D-Jet injection systems.  I’m going to post a static page on here with these links.  Hopefully it will be of use to others.

It was kind of warm today, though it felt otherwise while I was giving the 14 a good wash and detail.  It still had a failr ammount of grime from ibeing in the garage for so long, and it took a couple of passes to get it really clean.  I even got to do some spot detail removing surface blemishes with polishing compound.  With the exception of a few minor spots it looks like it just rolled of the line in Germany.  I still need to work on some of the rubber, but it’s a beaut.  The interior looks almost new as well.

I gassed up again this morning and the numbers run slightly over 15 mpg.  Very disheartening, but this was prior to tuning the fuel pressure.  I’ll have to drive it more and run the numbers again.  I would live with 20, be happy with 25, and anything above that I’d be ecstatic.  I have a link to a review of a 73 2l that claimed 25-35 mpg.  Time and tuning will tell.

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