CTS may cause issues, but from what I've seen, it just makes the vehicle run poorly. Often too rich as they seem to fail thinking the engine is cold. You can run a continuity test between the two terminals, I noticed that the reading (which is resistance) I got from the CTS and the temperature sending unit (the one for the gauge in the drivers side head) came out the same. So I suppose you could check those two and see if they are close.
No spray from injectors needs to be figured out. The CTS will never cut fuel completely to the injectors. Likely culprit is within the distributor. You can check for 12V on injector leads (don't recall which, but one wire is ignition 12V, the other is a switched ground through the ECM). If you've got power to the injectors but an intermittent problem, it is very likely to be on the ignition side.
You can test the module, coil, and pickup coil, it will be in the service manual for your rig, conveniently found in the link in my signature block below. I noticed that one of the TBI years ('88?) has the C/K service manual, not the R/V, but any of '87-91 R/V manuals will be correct for testing those components.
Pretty good bet anymore that if one component in the distributor is bad, it's better to just go get a complete distributor from the auto parts store. The pickup coil requires you to remove the distributor to replace anyway, and the sum of all the parts (assuming "cheap" parts store brand ones) is more than the cost of a complete replacement distributor.
Fun test if you have a spare distributor, disconnect the wiring to yours on the truck, and just hook the spare up to the wiring. Turn it with the key in run. If the injectors spray, there is something wrong with the original distributor. I'm not positive, but the spare distributor may need to be grounded to the truck for that to work.
