Won't Start - Got Diag Codes, Now What?

[bss2692]

I'll try and keep this as UN-Noob" as possible...and as informational(withholding opinions as much as poss too.)

 

2003 GMC 1500 Z71 5.3 BONE Stock

It recently was having a Little difficulty turning over, slight hesitation, but once running All's fine. the pic shows 157K miles, Oil Pressure running just under 80... that is ALL THE TIME, unless WOT for a few seconds on the road in gear....then it drops to ZERO, until it gets into 2nd gear, then it pulls back up to <80.. Again, this is all the time since I got the truck in January. Also, as this pic(which I'm trying to learn how to post) shows the Batery running at JUST BELOW 14v.. it USED to be about 14.5...but I think it's about drained from trying to turn over-and over- and over...

 

Now, it will NOT Turn over by itself, and have to get a jump. once it turns over, again, runs fine, never stalls.

now - from a cool engine, it will crank about 4 times, and then just Stop... the batt is 10V or less..and just Dead. This is a Two yr old battery...I think. I don't have any info on the truck in it's past life from my brother (he doesn't know what a dipstick from his... ANYWAYS)

 

 

I ran down to *'reilly, and got them to do an Engine Diag.... the Chk Eng. light is NOT ON.. EVER..

They did a Diagnostic and found 3 THREE! errors...

 

P0120:

TPS Sensor A Circuit

Possible Sensor Circuit Malfunction

P0220: ( I THINK)

TPS Sensor Switch B Circuit Malfunction

 

P1516

Manf. Cont. Veh. Spd.

Idle Spd. Cont. Aux Input

 

 

THAT is what they read on the Diag box... I wish I got a printout or something, but I had to use a crumpled napkin.

 

so - WTF? I was thinking Alternator... but - it would run Fine (for 50+ miles) and not die out.

i Can turn it off, and crank it back up IMMEDIATELY..but if i wait about 10 minutes... same thing, no turning over, and dies after 5-6 cranks..

 

Any help is REALLY Appreciated... I want to keep this nice truck running for at least 2 more years... and want to keep it running nicely!

 

PLEASE HELP! THANKS!

 

 

 

 

[Bowler807]

It sounds to me like you have a bad battery. Since you don't know how old the battery is, I would replace it and have the charging system checked.

[bss2692]

Will try that.

will let you know what I find out .

 

TO ALL : Any suggestions on type of battery? I don't think i need an Optima Super Double Platinum...but then again, I'm willing to spring for something More than WallyWorld Garden Battery...

 

just a good "Bang for your buck" "I'm happy, no problems here" battery...

[nickvrebel]

usually a mid line store brand battery will do the job for most people. If you are in the Northern areas a Gold series may be better suited for cold mornings.

[Made_N_USA]

Here is some info for ya.

 

P0120: This would explain why you are gettting hestitation, etc... *read below.

TPS Sensor A Circuit

Possible Sensor Circuit Malfunction

The TP sensor is used to determine the throttle plate angle for various engine management systems. The control module provides the TP sensor a 5-volt reference circuit and a low reference circuit. The TP sensor then provides the control module a signal voltage proportional to throttle plate movement. TP sensor 1 signal voltage is low at closed throttle and increases as the throttle opens. When the control module detects that the TP sensor 1 signal or TP sensor 5-volt reference voltage is outside the predetermined range, this DTC sets.

The control module commands the TAC system to operate in the Reduced Engine Power mode.

P0220: ( I THINK)

TPS Sensor Switch B Circuit Malfunction

this code is relative the one above. I would Inspect the throttle actuator control (TAC) module connectors for signs of water intrusion. If water intrusion occurs, multiple DTCs may set without any circuit or component conditions found during diagnostic testing.

P1516

Manf. Cont. Veh. Spd.

Idle Spd. Cont. Aux Input ?????

this dtc is for the predicted throttle position (TP) compared to the actual throttle position. The two values should be within a calibrated range of each other. Both the powertrain control module (PCM) and the throttle actuator control (TAC) module redundantly monitor the predicted and actual throttle position. This DTC sets if the PCM detects an out of range condition between the predicted and actual throttle position.

 

this will give you something to go after. None of the above issues will resolve your no-start condition (i don't think). However, you truck will run like crapola until you get it fixed. Let me know if you have any questions.

good luck!

[Wires]

+1 on the battery.

 

I have an 08 SD with 15k miles on the clock, and the OEM battery is screwed. Swapped it for an red-top optima and it's been fine every since.

 

From your gauges, it looks like the alternator is putting out the juice, so I doubt there is an issue with that (just under 14V).

 

 

I would get the oil pressure checked out though. "Normal" pressure isn't pinned to the 80PSI line. Could mean just a faulty indicator/sensor, or something more serious.