Starter amperage draw

[SUX2BU99]

I know it's not for 73-87, but it's for a Chevy still I have an 03 Tahoe with the 5.3 and the starter seems to be spinning slower than normal and the odd time hesitating and then spinning. Had it load tested and it was pulling 350 amps with a peak of 450. Shop said it should be 200 on average, yet Chilton manual says more than 350 amps should be considered suspect. What is indeed average? Is it on it's way out? I tried checking the wiring connections but you have to remove it just to have a peek. So tight under there.

Thanks.

[VileZambonie]

Did you check the current draw with it in the vehicle? If so 350 Amps is excessive. 220 max I would say.

#1 your battery needs to have a good state of charge and should be load tested first.

#2 when you test starter curent draw the ignition system needs to be disabled.

#3 Do a voltage drop test on the positive and negative side of the circuit. All you have to do is install your voltmeter across the B+ cable to the B+ post and on the negative side go from the batt - cable to the starter housing. No more than .3V is acceptable.

[SUX2BU99]

Excellent info, Vile. Thank you. It was done with the starter in the truck and they do a 3-part load test: battery (which is pretty new and was fine), alternator and starter. I don't know if they do it with the ignition on or off for the starter. They used some kind of Snap-On tool for it. I presume they just measure it while they crank the key over? Presumably they disabled the ignition so the motor didnt actually fire.

That's great to know about the voltage testing. That I can do, but the starter terminals are in a really tight spot and I could only tell what I am doing AFTER the starter is out which kinda sucks.