Hi all!

I picked up a 91 245 (manual trans, LH 3.1, 130K miles) a couple of weeks ago. The car belonged to a neighbor--she drove it regularly until about a year ago when it quit running (the black plastic air tube from the AMM to the throttle body was completely shot). If I can get it running reliably, it will probably go to my youngest son (and our trusty old '83 244ti will go up for sale).

So far I've replaced the broken air tube, plus new cap, rotor, plugs, oil change, all fuses, and fuel pump/LH relay. Also did the flame trap and all of the lines/fittings between it and the intake manifold. Car runs well now, but it cuts out momentarily on bumps--or when you close the driver's door (probably the other doors too).

When this happens, the check engine light flashes but doesn't stay lit (so I assume no codes set?). I've checked and cleaned the ground points at the top of the intake (for the AMM, etc.) and between the engine and the firewall. Also cleaned the terminals and connectors at the top of the coil. Checked the AMM per the Bentley manual and it's OK (~108 ohms at ambient temp)

When looking at the car last weekend, I noticed that the insulation for the engine speed sensor's cable was split for 2-3 inches just below where it connects to the main harness. I taped it up, but no improvement. Wondering if this could still be the problem. As I undertand it, the LH control unit has to "see" the engine speed signal before it provides "ground" to the main relay--if engine speed signal goes away, so does the ground. Problem is I can't figure out a way to check the speed sensor. Do you think I should just replace it?

Just curious--is there a particular way the main relay should be installed? Is it more sensitive to motion one way or another? The car seems to run better with the relay hanging straight down. Maybe there's an intermittent problem with the wiring harness between the ECU and the relay?

Are there any other things I should look at? I figured I would check every gound point between the battery and the ECU--then clean and check every + connection.

Sorry for the long post, but this thing has me stumped. Thanks in advance for your time!

Best regards,

Steve A-