98 Deville starting problemw

I have a 98 Deville with the 4.6 Northstar, has a difficult time starting up. It has 94000 miles, I just put new plugs in and checked the fuel pressure, it has 50 psig. It takes sometimes 2 to 3 times to crank up, but runs fine once started, at idle and seems to run fine on the freeway. It has new air filter and everything seems to be in proper order, but the starting is definitely not right. Any ideas from anyone as what to do next? One friend suggested getting the injectors cleaned by a dealer or other shop. Don't know about that, it runs well, usually if injectors are dirty it will run lousy on the highway. Any suggestions are appreciated.

If the wires are original you might want to take a look at them. I've found that when older, well cooked wires are disturbed during a plug change, often they become problematical. You might, at night in darkness, try misting them with a spray bottle filled with water to check for arcing.
FWIW
YMMV

Thanks for the tip, that was among my next "guesses" ---plug wires. Is there a way to check the continuity of plug wires? I have a cheapo depot volt meter that has a continuity check but don't I how it would apply to plug wires. Anyway, I checked the fuel filter and it was filty, I imagine the original and with 94000 miles well past due. I gained 2 psi after changing to 52 psi at the Schrader port, so that could have been part of the problem. These idoit dealers don't recommend changing plugs, fuel filters, antifreeze, transmission oil until 100k miles, which I believe is nuts. No more than this stuff cost, it's cheap insurance. The plugs at 94k miles were clean but the gap was much wider than the 0.050 recommended and had burnt out to .070 or better.

Your antifreeze is past due. I believe it is 5 years/100K miles, which ever comes first, for the Dexcool. I'd do the tranny fluid, too. Rebuilds on 4T80E trannies are pricey.
You can check the plug wires for resistance with an ohmmeter. While you're doing it you can flex the wire and watch the meter looking for fluctuations indicating an internal break. The allowable resistance figure is based on the length of the wire. It should be on the net somewhere. Truth be told, with eight years and 94K on them, you're due for new wires anyway. I recommend sticking with ACDelco.
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