Newer truck feul problems

[WI_Jeff]

I know you guys deal with older Chev trucks. I'm good with them myself. New stuff drives me crazy! I have a 1989 Chev S-10 with the model 220 throttle body. Ran great until 2 days ago. Then she would not start. Primed the throttle body and it started and ran great. I replaced in tank fuel pump. Same thing. I have to prime it to start it then it runs great. Color me stupid, but I can't think what else it could be. Not at all up to date with fuel injection of any type. Any ideas would be greatly appreciated.

[kevmic28]

Clogeed inline fuel filter maybe???

[bwood]

Make sure you hear the fuel pump priming when you turn the key to run but it sounds like a ignition module issue. It is located under the rotor in the distributor. The module has a start and a run mode and in the start mode, it is looking for th e starting rpms (under 400). Once it sees the low rpm cranking, it gives a reference pulse to the ECM to fire the injectors. Once the injectors start firing and the rpms climb, it goes into the running mode and starts to control the injector firing rate. When you prime it, it spins up enough to get into the running mode. You can have the module tested at the parts stores for free, just make sure they test it a bunch (I usually shoot for a dozen times in a row). The module heats up as its operating and can pass when cool and fail when hot. When you remove or replace the module, you have to make sure that the white heat sinc compound/grease is in between the module and the dist base or it will fail. The heat generated in the module is disappated through the distributor body, no heat sinc compound, module will overheat. Make sure its heat sinc compound (should be white) not dielectric grease.

[WI_Jeff]

Thanks a bunch!!!! What happened to gas and spark and it runs?