My car is doing some weird stuff…
When I take the car out for a drive from cold, it runs great. Let’s say I stop at the store after the car is at operation temperature. When I get back in, it starts up fine. When I start driving, it seems fine. Then bam! At idle, the rpm’s drop to almost nothing for a split second, kind of like I turned the car off… and then, miraculously, it goes back to idle. This phenomenon also happens when driving at low speed/rpm which results in the car nose diving in a less then pleasant manner. The good news is it hasn’t happened at speed or high rpm.
Only changes I can think of is the weather is getting warmer here in NC and, last month, I switched from Bosch platinum plugs to NGK’s.
I tested the ignition, seems to be firing correctly for extended periods. I also checked the mixture and found it to be running lean- set it correctly. It definitely runs smoother now, but no change to the engine cut-out problem. Always get’s BP Amoco fuel.
Any thoughts?
For reference and to demonstrate that I baby my car, here’s how she’s set-up
It’s a ’74 911S Targa, rebuilt 15k ago. Stock CIS, Crane ignition (should have done MSD?), upgraded oil cooler, turbo valve covers, Carrera tensioners, upgraded fan, upgraded head studs, koni’s and 23/29 torsion bars and any other 2.7 things I may have forgotten. Definitely need some Fuchs and turbo tie rods… after I get this issue sorted out
Thank you.