I have a '92 S-10 Sonoma with 51,000 original miles. It is a 4.3 V-6, 5 speed standard transmission, extended cab. Has A/C, PB & PS and not miuch else. Every 4-6 month the truck (http://chevytruckworld.tenmagazines.com/ew/topic.asp?id=178948L#) starts running a little rough, even with the A/C off. After about a week or so of this, it won't start, cranks fine but no spark and no TBI fuel being injected. On rare occasions, such as yesterday, I can let the truck sit for a couple of hours, and after moving and fiddlng with the two module connections, the truck will start. It made it home, stalling twice but restarting. Today it won't start for anything no matter what is done to the connectors.

Every time this happens, I install a new ignition module (http://chevytruckworld.tenmagazines.com/ew/topic.asp?id=178948L#) and everything is fine for another few months. This is a problem of the last two years or so, before it was perfect. I have replaced 4 modules in the last 18 months.

The plugs are relatively new, the wires the same. Have run the truck at night with the hood up, don't see any sparks (http://chevytruckworld.tenmagazines.com/ew/topic.asp?id=178948L#) or lights. The ignition module connectors have been cleaned and lubricated, they are tight when installed. The proper grease is used under the module, it is tightened evenly and snugly, but not overtightened.

Does anyone have a similar experience or see something I am missing?

Thanks.

Is it a delco module?..these jap modules (which borg warner is as well) are junk..

you can make SURE its the module test lite and some patience...I have no idea of your tools/mech knowledge,but its pretty simple.

key on

unplug 4-wire connector at ,module...leave 2 wire connected

pull a plug wire off and install a spark checker

watch your tbi injectors

attatch the test lite to B+

look at your connector...there is a purple wire.....MOMENTARILY touch the purple terminal with your lite

the spark should jump once and the injectors will give a shot of fuel..

If that does happen,then you know your ecm,coil,pole piece.cap,rotor,injectors,wiring are all good...it HAS to be the module.

Thanks for the suggestions. I will certainly check the module as you said. Since the truck is my work truck and I work out of the country, it is real inconvenient when it dies. All the parts here are Chinese replacement parts. I am at the stage of going to GM and simply buying everything new, coil, pickup coil, module, wires, plugs, distributer cap, rotor. At least then I will be starting with a clean slate. Just replaced the alternator in December, so that should be good and is not a common factor for all the failures.