1987 Chevy Truck Won't Start

[Buick Power]

Not sure where else to go, seems like this is one of the best boards for everything.

My 1987 Chev truck 305, TBI won't start. It wouldn't start last week and then when I checked it Saturday night it started right up and was fine. Sunday I ran errands with it throughout the day. Went to start it Monday and it wouldn't start.

Here is were I am at now. Engine cranks fine. Battery is 12+ volts. I put a little fuel down the TB and it didn't fire and I think I can hear the fuel pump, so I am leaning towards electrical. With key on all wires at the coil show voltage with a test light, at least one wire for all the different electrical connections show voltage with the key on. The only connector that had zero voltage at all the pins on the connector was the four wire plug to the module in the distributor. The distributor is essentially an HEI with the coil seperate. I bought a Chilton manual but it does not show my type of distributor. I'm pretty sure it is the correct ignition, because I got a replacement coil and it was exactly the same as what I have. I temporarily changed the coil and no difference.

Going by the wiring diagram there is a fuse between the engine control module and the starter. At first I ruled out fuses because it ran over the weekend. Just need to know where the fuse is.

To tell you the truth, the distributor in the back is throwing me, I can't see a damn thing. On the Buick's I just pull them out if I have to troubleshoot anything. I can't even find the distributor hold down. I'm also tired and cranky too.

The troubleshooting guide in the Chilton book is a little akward because it is all fragmented. Hopefully, someone has some experience with one of these. Also, I would like to know where the engine control module is located. I am not trying to get out cheap, just don't have the time to tear half the truck apart. I could change the module, but I don't want to deal with the distributor IF I don't have to. Thanks in advance.

[GSXMEN]

I suspect it's the Ignition Control Module, located under the cap & rotor. Don't forget to smear some heat transfer lube under the ICM when you re-install. :Smarty:

Should you need to pull the distributor, the bolt is a 9/16". Might need to bend a crappy wrench to get the right angle - unless you have one of those special dist. wrenches.

How old are the plugs? Had a friend keep trying to fire up his Chevy truck on a yr. old set of plugs. They got pretty wet.....I suggested some new ones. Once the new ones were in - it fired right up.

[Buick Power]

Yeah forgot to mention the plugs look good, nice and clean and no material loss.

Dave

[LARRY70GS]

Dave,
Another possibility is the pickup coil in the bottom of the distributor. I had an intermittent no start for months that was driving me nuts. Changed everything in my HEI, except you guessed it, the pickup coil. When I changed that, the problem went away for good. Usually when the module goes, it goes for good. To replace the pickup coil, the distributor must come out. These tests may help.

[Rivman]

My '89 350 TBI just quit running one day (in the middle of a nieghbors driveway) and refused to start - lots of fuel/battery.
Tested the Ignition Control Module per a Haynes repair manual and that was the culprit, - about $80 bucks new from Mr. Goodwrench.
(. . . a fairly common problem on older models !)
Replaced the faulty module and truck fired right up ! :beer :TU:

[Buick Power]

Looks like it was the module. Started right up after I switched it. Will see for sure in the AM. Thanks for everyone's input.

Dave