I spent some time trying to find an answer before posting this so it looks like this module hasn't troubled anyone else but I can't find it and I'm wondering if there is one on this model year. I've got the doghouse and air cleaner off and the only five pin connector I've found looks way too big for the picture I'm looking at. Could it be incorporated into a bigger unit or am I just not seeing it somewhere. The sensor came off real neat in ten minutes, I thought the module would be a cinch but it ain't there. (as to why I'm changing it, the engine started knocking a little under load, I could hear it only with the doghouse off, it doesn't throw a code number because the light goes out every time I shut the motor off and doesn't show up again until under load, still runs good enough but ya can't knock long before it all goes south, the parts are cheap enough so that's that) Anyway, I'll leave it at that, if anyone has an idea where the spark control sensor is on a 1991 5.7 van let me know. I'm gonna go stick my head under the steering column one more time.....Phil

 

If you are talking about the ICM - ignition control module - my guess would be inside the distributor - but I don't think your symptoms to go with that part failing.

 

Ignition Control is in the distrubutor.

 

Thanks for trying guys but as I said I'm looking for the "electronic spark control module"

 

Here it is, but not 100% sure of its location, in the distributor?

 

I would have thought the distributor as well. I was glad to open the thread and see that my older rough knowledge was correct. The part you list, is that not some aftermarket third party add on? It does not look like a GM Part.

 

Looks like it's located on a bracket bolted to the rear of the passenger side cylinder head. Edit: Maybe not, looks like the picture is of a 6 cylinder.

 

Well then my guess that is what it is and that is where it goes. I should have been quieter with my words.

 

I checked inside the distributor and found nothing except the Ignition Control Module and it is not bolted to the cylinder head near the distributor either so I'm thinking that I will just replace the Electronic Spark Control Sensor and hope that it does the trick. I've searched all over (and under) for the Electronic Spark Control Module with no success so I'm beginning to question if there is such a thing on the 1991 model. I'm using the Haynes manual for 1991 Chevy vans and have already found that the illustration for the location of the sensor is incorrect, they show it located on the drivers side but I discovered through the internet that the sensor is in fact located on the passenger side just in front of the starter motor (there is a sensor on the drivers side but it ain't the Spark Control Sensor) so if the Haynes manual states wrong information about that they might be wrong about the Spark Control Module too. Anyway, maybe this conversation will help someone else with the same problem. Thanks for all the help, I'll let you know how it goes from here. Phil

 

Hi, RockAuto and Autozone have the module, but don't see a sensor? Are you referring to the Knock Sensor?