Intermittent Starting - another one
 

1990 C2 Tiptronic - Having intermittent start issues - starts cold fine. After getting to engine temp, it's difficult to start - can hear everything cranking but to get it going I need to give it some gas and usually it'll usually start around the third time.

When it starts, the idle hunts for about 15 seconds before settling in at 750rpm - other than this, car's running fine.

Have done the following to no avail:

Changed DME relay
Replaced battery
Replaced battery ground strap
Added Lubro Molly fuel injector cleaner and valve cleaner with fresh tank of gas

I'm without access to Bosch Hammer or other diagnostics - is there anything else I might be able to check myself before turning her in to the shop with my credit card? TIA for any thoughts.

Idle Speed Control Valve
 

My high miles C4 has a tendancy to hunt for idle also. Sometimes I have to turn it over a couple of times, but as long as I don't give it gas, the idle stablizes itself. If I try to give it gas or move it before its good and ready, it will stall and hunt again on restarting.

It really should start without hitting the gas, let the ECU run through it's loop. There might be something else in play, but I think you are on the right track with cleaning the intake. If you can get it started and keep it running, the cleaner should help.

Hope this helps

I've replaced the coils and cleaned my idle control valve to fix my hunting idle and stalling issue. Mine also starts after 10 seconds of cranking once in a while on hot days. I haven't tested it enough to know it the hot start problem is gone...

My next step is removal and professional cleaning of the injectors.

I suspect spark plug wires could cause an idle issue.

Try running a bottle of Techron thru it first.

2nd on the Techron. Use a full bottle on a 1/4 tank of gas and take it for a nice ride at high RPMs.

I had this exact same problem. I recently rebuilt my engine along with have my fuel injectors tested and cleaned. I presently have about 700 miles and starts fine so far. Knock on wood.