Starter engages but no crank

[P_nlsn]

Dash lights come on, radio comes on, I hear the brake booster charge up when the key turns on, everything seems to be working fine on the truck - it just won't try to crank. The immobilizer light blinks until the key is inserted, then it turns off. Truck ran fine when I parked it last week and haven't had trouble starting it in the past. Battery voltage is good (12.4v sitting, 11.9 key on, 11.3v starter "engaged"). Double checked it wasn't just low voltage by trying to start it with a jump pack hooked up, no difference. Checked voltage at the starter lug and got 12v as well.

I can hear the starter "engage" forward for a few seconds when I turn the key, but it makes no attempt to spin the flywheel. I tried it in park and neutral, and while moving the shifter.

ScanGauge is reading pending codes p0335, p0340, and p0345. That made me think rodent damage since it's parked outside, but I can find no visible damage to the sensors or wiring harness, or any other evidence of rodents in the vehicle.

I knocked the efi and starter relays on the bumper to check if they just got hung up. No change. Double checked them with a volt meter and their continuity was good. I didn't have a jumper wire to check that they flipped when powered though.

I've heard mention of a bad COR possibly causing similar issues, but I can't find any documentation on where it is located so I can check it.

I also put a wrench on the camshaft bolt and made sure the engine wasn't seized somehow.

Next time I work on it, my plan is to make a jumper wire for the starter relay to try and force it to spin and make sure it isn't a bad starter. EDIT: I also plan to knock the starter and see if it's a bad spot in the contacts, as well as checking for voltage drop and bad grounds.

I'm not sure if the codes are keeping the ecu from cranking the engine, or if the problem keeping it from cranking is also throwing the codes. Anybody have any ideas on what could be causing these issues or what to check next?

FIXED: Swapped my starter for a used spare I had kept and it started right up. I guess my starter was bad :shrug:

 

[Buckaroo]

Dash lights come on, radio comes on, I hear the brake booster charge up when the key turns one, everything seems to be working fine on the truck - it just won't try to crank. The immobilizer light blinks until the key is inserted, then it turns off. Truck ran fine when I parked it last week. Battery voltage is good (12.4v sitting, 11.9 key on, 11.3v starter "engaged"). Double checked it wasn't just low voltage by trying to start it with a jump pack hooked up, no difference. Checked voltage at the starter lug and got 12v as well.

I can hear the starter "engage" forward for a few seconds when I turn the key, but it makes no attempt to spin the flywheel. I tried it in park and neutral, and while moving the shifter.

ScanGauge is reading codes p0335, p0340, and p0345. That made me think rodent damage since it's parked outside, but I can find no visible damage to the sensors or wiring harness, or any other evidence of rodents in the vehicle.

I knocked the efi and starter relays on the bumper to check if they just got hung up. No change. Double checked them with a volt meter and their continuity was good. I didn't have a jumper wire to check that they flipped when powered though.

I've heard mention of a bad COR possibly causing similar issues, but I can't find any documentation on where it is located so I can check it.

I also put a wrench on the camshaft bolt and made sure the engine wasn't seized somehow.

Next time I work on it, my plan is to make a jumper wire for the starter relay to try and force it to spin and make sure it isn't a bad starter.

Anybody have any ideas on what could be causing these issues or what to check next?

I would guess bad starter. Give it a couple of whacks on the side of the motor with a heavy wrench and see it if goes. If not, do a voltage drop test on the power wire going to the starter.

 

[MikeinNH67]

Make sure you don't lose power because of a dirty connection, at times the high load of the starter can make a dirty connection show up. This can be seen by watching the interior lights as you turn the key.

Assuming that is good, I would check voltage to the starter (at the starter) and the smaller solenoid when key is turned to start. If all is good, check to make sure the starter is grounded well. A bad CPS connection wouldn't stop it from spinning but I wonder if it could set the code because of a bad ground, you list both banks with codes. Having watched Pine Hallow Auto's video below recently makes me think of a bad ground.

https://www.youtube.com/watch?v=eKcTHCWcSgE

 

[P_nlsn]

I would guess bad starter. Give it a couple of whacks on the side of the motor with a heavy wrench and see it if goes. If not, do a voltage drop test on the power wire going to the starter.

This is a good idea. I should've thought of this sooner - My brake booster did the same thing a couple years back. Had a bad spot in the contacts and a couple taps with a wrench would get me home when the buzzer went off.

Make sure you don't lose power because of a dirty connection, at times the high load of the starter can make a dirty connection show up. This can be seen by watching the interior lights as you turn the key.

Assuming that is good, I would check voltage to the starter (at the starter) and the smaller solenoid when key is turned to start. If all is good, check to make sure the starter is grounded well. A bad CPS connection wouldn't stop it from spinning but I wonder if it could set the code because of a bad ground, you list both banks with codes. Having watched Pine Hallow Auto's video below recently makes me think of a bad ground.

https://www.youtube.com/watch?v=eKcTHCWcSgE

This is a good idea as well. With the winter storm a month ago, I wonder if some salty road gunk didn't get rinsed off and maybe corroded a ground. I'll have to give those a look over.

Oh boy, the joys of finding electrical issues

 

[P_nlsn]

Ok I finally figured it out

After confirming the starter relay was good and cleaning up the battery terminals and grounds around the starter, it still wouldn't crank. So I pulled the old starter out. It still spun with direct power, but I swapped it for a used spare I had and the truck started right up with no codes.

I'm not sure what happened, because I had no symptoms of a weak starter that I noticed before hand, but I guess even though it spun off the truck, it was too weak to crank on the trunk. I'm also not sure why that resulted in the pending p0335 p0340 p0345 codes either, but now they're gone