I have a 97 silverado,5.7 vortec,2500....... perfect runner, but.... when cold it will spin and start right up with no problems. Let me drive to the store and come back out 15-30 minutes later, hit the key and acts like the battery is weak, very weak... battery was replace 9 months ago, but will crank slow slow slow and then starts. let it sit for about 1-2 hours and hit the key, bingo instant start and spins over fast. Starter does have the heat sheild, could it be the starter?? Thanks

 

bypass the solenoid and see if it start when warm

 

my burb did that after checking all he cables and putting a heat shield on the starter, i replaced the starter and it fixed it, i got one of those PMGR starters and it sounds great and it really kicks the motor over i got it from Starters, Alternators and more for Cars, Trucks, Tractors and ATVs

Sean

97 4x4 burb

 

After it starts from being sluggish do you recognize higher charging voltage? Mine was doing the same but exact opposite. Mornings it would start like battery was dead or very sluggish, afternoons it would start right up. Turned out to be the smaller wires coming out of the battery terminal. Had to investigate pretty deep though at first glance the wires looked good. Inside the insulation was all white powder though. Changed the battery terminal wires and problem went away.

goood luck

 

Hard hot starts can be caused by the same things that cause hard cold starts. Defective or too small a battery, faulty cables,or starter,missing grounds. Without some test equipment you are guessing.

 

usmarine - did you ever find out what was wrong? i have same issue on my 1997 K1500 (376,000 miles) and i have replaced new starter, distributor, alternator, plugs, wires, battery, battery cables, and cleaned all ground contacts.. mine still does it, and only after warmed up.

 

That symptom is ALWAYS caused by shorted field windings at the starter.

Allan

 

44Fore............ Yes I did it was a bad starter. I purchased the better one from Advanced auto.... it was 99 dollars, it was not the OEM starter replacement, it was the next one up.. looks much smaller and thiner, but works great... still working great today......Good luck

 

44 Fore....... I mis spoke, sorry, the cost was 119.00, from advanced auto parts. It is much smaller and lighter, and spins the engine over much much faster, my part number was 96120, urs might be different depending on the application... Good luck, BTW I found a 40 dollars off coupons on the net, helps a lot.