[scotsman60]

My '90 C2 is pinging. In fact it's been pinging for a while but I can drive around the problem. This week we had 90+ temps in Souther Californai and the pinging is getting to be annoying enough for me to do something about.

Here's what I've got and what I've done so far,

1) I'm running 91 octane gas - it's the best I can get here.

2) I've run a bottle of Techron through the system and it didn't make any noticeable difference. (I changed the oil afterwards)

3) New plugs, new leads, new distributor caps, new rotor arms and new coils - No difference.

4) I'm getting a spark on all plugs - distributor drive belt checks out OK


I've got some questions,

1) If the knock sensor detects pinging and adjusts the timing at any time should I get an engine warning light? (I haven't got any lights)

2) I'm thinking of hooking my DVM up to the knock sensor wire. Anybody got any ideas about what kind of signal I mugh expect to see and how it should change when pinging occurs? (I'm going to assume to start with that I'll see constant voltage and then a change in voltage as pinging is detected)

3) It's possible that the knock detectors are either faulty or incorrectly attached. How do I access them? If is remove the fan and the alternator can I get access to them? If I'm in there I'll probably replace them anyway - any special things to know about this procedure?


Any and all ideas and suggestions gladly accepted......






Doug