2006 Buick Rendezvous, 3.5 motor, 2 wheel drive Car will not start randomly. Starts first time in morning. Usually starts after sitting all day at work. If I drive around for 10 to 20 minutes, shut off and go back to restart the car, randomly does not start. Sometimes start normal for a couple of days. Yesterday I got stranded for 2 hours waiting for a tow truck but it restarted just before the tow truck got there. What I have done so far: I had a mechanic check codes, no codes~no warning lights. I replaced the starter relay, that seemed to help. So, when it happened I would pull out the starter relay and put back in. That worked several times in a row. Then yesterday happened and I tried my trick multiple times but it did not work~so I know that is not what has caused the problem. I saw the post that suggested holding down the accelerator while starting to see if it is a flooded condition, I will try that in the next day or two. Thank you for the help!
You need to explain what “will not start” means. Does the car crank normally without the engine starting? Does the car crank slowly or differently? Does the car not crank at all? Do any lights come on when you turn the key?
I am sorry for not including more information. So, what happens : normal start ~ starts just fine and all the lights go out. When there is a problem, engine cranks over as usual but acts like no fuel. It sputters a little bit but will not start. No lights stay on except battery light because the engine did not start. If I turn the key on and try to start it, and it has the problem, turn the key off but the engine does continue to try and start for a few more seconds before it stops. No lights stay on, like service engine soon. No error codes either.
The Buick has 171000 miles on it. Today it left me stranded at work. I drove to work just fine in morning, about 5 miles. After I got off of work, the car would not start. It cranks over just fine but will not start. No lights on the dash came on. I had to call Triple A and had the car towed to my mechanic. After towed and drooped off by the tow company, the driver tried to start the car and it would not start for her either.
Cranks ok but won’t start is almost always either a fuel or spark problem. So that’s the first thing your shop has to decide, which of those it is. Since it seems to be more of a problem when the engine is has recently been running and remains warm, I’d guess this to be some kind of spark problem. Probably a failing crank position sensor or ignition module. Checking for spark at the spark plugs is how to test for those. Less likely, the fuel pressure is leaking down for some reason. A fuel pressure test is what to do for that.
This is from way out in left field, but-
I’m not sure why you replaced/wiggled the starter relay, when it sounds like the starter has been working the whole time, but there might be the slightest chance that when you were wiggling it, you were flexing the power distribution box enough to help a bad connection on the fuel pump relay.
Just a guess.
The crank sensor was replaced, still had problem after that.