Have an 98 LeSabre 3800 V6. Will do nothing using ignition switch. Jumping the solenoid engages starter and motor cranks as normal. Cranking with key in run position car doesn't start. haven't checked for spark and not sure how to check for fuel. Have checked all the fuses I can find (under drivers side, passenger side, under hood at firewall. All relays seem to be plugged into their positions properly. Ran fine, Stop for a drink at the CS and wouldn't do anything when ready to leave. Been a few times that this would happen when starting but after releasing the switch it would do ok the second time. Any ideas as to cause and troubleshooting to verify the problem?

 

Certainly sounds to me as the safety switch is intermittent for making sure tranny is in P or N for starting. Have to have my brake pedal depressed also for push button start (key start must be the same?). Imagine tranny is auto not standard with almost any Buick?

Aside from checking switches (probably impossible locations) maybe try extra pressure or try moving shifter while turning engine over. Don't take out of gear but check for mechanical looseness (brake pedal also). Car is 20 years old and no mention of mileage?

 

I tired working the shifter while having the switch in the "start" position, Can't remember if I had my foot on brake or not but likely so as the shifter went in & out of park with no problem. Yes, auto trans. & about 180,000 miles. Normally runs great. I had a 96 Park Avenue that I gave away with 256,000 miles that was still a dependable daily driver, The lady we gave it too (4 years ago) still uses it all around the city. Anyone know where the fuel pump relay is located?

 

Just guessing on what problem might be with starting, what I'd check first. Somebody here mentioned about fuel pump circuits being under rear seat and trouble with seat frame braces chaffing wire harnesses. See if I can locate- It's current in Buick Lucerne forum, no idea if other Buicks follow suit.

Again, would be nice if others that actually know Buicks would put some answers up. Our first one ever is a '16 LaCrosse, really like it. Bought it just to drive around listening to oldies with the windows rolled up. One of the first commercials for car but loved the stance lol.