I have a 1998 GMC Suburban that I had the fuel pump replaced on in June of this year. Shortly after it started to have issues starting. Thought it was a faulty fuel pump as it would roll over fine just not start. My mechanic checked it and fuel pump was fine. He then checked the plugs and said they were badly fouled so he replaced them. I brought my truck home and did not drive it for 1 day. On the second day I went to start it and it rolled over but would not start. I was going away for a month so called my mechanic and told him the truck is doing the same thing and I would bring it back when I returned. I pulled the battery ground cable off so my battery would not die while I was away. When I returned it would not start but rolled over fine. I had it towed to the shop. When the mechanic tried to start it it started right away. He tried it a few times and it started each time. I brought it home. The next morning, cold start, it rolled over but would not start. I called mechanic and took it back. He kept it overnight and tried a cold start and it started fine. He did all kinds of tests and said the Mass air flow sensor and another sensor were gone so he replaced them both. Brought it home again. Next morning cold start it rolled over once without starting, second rollover it started but ran really rough then stopped the third time it started ran rough briefly than smoothed out. I called him and he said bring it back. I did some errands on the way to his shop, so stopped and started a few times. On the 3rd stop I turned it off and when I went to start it 10 minutes later I turned the key and nothing, no click, no roll over nothing. The third time I turned the key it rolled over and started. I drove right to the shop. He kept it over night and it started fine in the morning. He tried a couple times during the day and it started fine. He said he could not find anything wrong. When I went to pick it up I asked him to come out while I started it. Finally, I turned the key and it rolled over but would not start. He was shocked. He said it never did that all the times he tried to start it. He did more checks. no luck. Today I went again to pick it up and when I got there he had the engine bonnet up. Before I arrived he went to start it and it would only roll over. He figured it had to be the distributor module. He ordered the part and I came home without my truck. I called this afternoon to see when I could come get my truck and he said it still was not starting with the new module. He is going to work on it tomorrow morning to see if he can find the problem. Any suggestions would be helpful if you have had this issue, as both the mechanic and myself are very frustrated. Thank you so much.