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2003 Impala 3.4 intermittent starting issue

I have a 2003 Impala 3.4 with an intermittent starting issue. It starts perfect every morning but after it is hot and I park it over 15 minutes or so it will sometimes not start. All the regular dash lights come on as normal but when the key is turned it does not even try to turn over, it is just silence, To get it started I have to hit the column shift lever upward several times and then it will kick right off with no hesitation. Sometimes I have to turn the key 10-20 times to get it started also. I had the battery, starter and alternator tested under load and they are all fine. It is not the security problem either that many impalas have. The only code I have is a PO 336 for crankshaft position sensors. Is there some kind of linkage in the column that could be worn that could cause this? Thanks

“To get it started I have to hit the column shift lever upward several times and then it will kick right off with no hesitation.”

There is your “smoking gun”, so to speak.
More than likely, simply replacing the Neutral Safety Switch will remedy the starting problem.
The next time that it does not start, try shifting to Neutral. If the engine starts readily in Neutral, that is your confirmation that the Neutral Safety Switch is the source of the problem.

Thanks, I will try it the next time it happens (probably tomorrow). I had a friend mention that it could be the neutral safety switch. It will not start in 1st, 2nd 3rd, or D. It was nice of GM to put it inside the transmission case on this model. $800 in labor to get to a $30 part.

"It will not start in 1st, 2nd 3rd, or D.

Well, at least the NSS is operating as it should to some extent!

In GM’s defense, I am not aware of an issue regarding GM Neutral Safety Switches.
This problem was common on older Fords, but I don’t recall it as an issue on GM products.
On those older Fords, the “workaround” was to place upward tension on the shift lever with your left hand while the trans was in Park, turn the ignition key with your right hand, and almost always the engine would start.

All of that being said–I agree that GM should NOT have placed the NSS inside the trans case.

It doesn’t sound like the neutral safety switch is bad, just out of adjustment. Can it be adjusted from the outside? Can the shift linkage be adjusted?

The Impala did not want to start 3 times today when good and hot. I put it in neutral and tried it and it did not start. Tested it in going from Park to Neutral at least 10 times and did not start in either. Had the battery tested again and it tested just fine. I noticed when it did not start when I was turning the key to try to crank it that the retained accessories relay in the driver side box was clicking loudly. I pulled the relay and it started right up while I was in the middle of the no start condition. Does this make sense that the retained accessory relay could effect the starting? I appreciate all the help.