Crank but no start

[PLohr]

I have read a handful of threads but have not found this specific scenario yet.



2003, SRW, 2WD, manual transmission. Completely stock.



The batteries had been out of the truck for about 4 weeks while I was rebuilding the front suspension. The batteries were on a reconditioning charger.



Prior to beginning the suspension rebuild and taking the batteries out, the truck had been running fine.



Finished up the front suspension rebuild yesterday. Installed the batteries. Turned the key to the on position - low fuel light is on, volt meter never rises off its rest, fuel gauge never moves, check engine light stays on. It is suspicious that the gauges are not functioning. Grid heater does not run - light comes on then turns off quickly. But I never hear the grid heater's contacter close and open. The lift pump did not run - this is usually audible. So of course the engine cranks but does not start.



Knowing the fuel level was around an eighth of a tank 4 weeks ago, I put in 10 gallons of diesel. Still, the fuel gauge does not rise, the low fuel light stays on, the lift pump does not run, so of course, the engine cranks but does not start.



I have tried retrieving the codes using the key on / key off trick in 3 cycles and 4 cycles - I never get any codes on the odometer.



The next thing is to maybe buy one of those inexpensive scanners.



Any ideas?



Thank you for any help,

Paul Lohr

 

[jelag]

How about the batteries are really not fully charged or their in backwards...

I know in the winter when I put small chargers on some of my stuff that's away for the winter that 3/4 - 1 amp charge is easily stopped from simple corrosion on the posts. . Often I've got to go back every few weeks and make sure the light is green (charge) and not red (no connection)

 

[BK]

Do you have a digital voltmeter?
Can you measure the voltage on the terminal of the batteries when the key is "on"...

Also, then measure the voltage while on the lugs of the cables (not the battery posts)...

If the battery voltage is at or below 10, all bets are off.

If your at 12. 6, things should be ok for computers to be working and the gauges should be doing the right things.

Good batteries off of charge should show at 13+ just off of charge.
Once loaded (not during cranking), they'll go down to their natural terminal voltage, 12. 6 and should stay there for hours with a nominal load on them.


Did you do any welding on the truck while you were doing this work?

Where there any grounds you unbolted from the fenderwells / frame / block that you might have forgotten to bolt back up?

 

[PLohr]

Thanks for responding, I appreciate your help gentlemen.



Batteries read 12. 75 volts with the DVM. The motor will crank over and cranks strongly. It just never starts.



Batteries in backwards? I don't think so but it is worth double checking.



I did some welding but none of the pieces were on the truck.



Good point about the grounds in the area I was working. I will check that, thank you for the suggestion.



I checked voltages at the MAP sensor and IAT sensor. Both have a supply voltage of around 6 volts coming in. Not sure the voltage is correct but it does indicate the ECM is doing something.



I am wondering if the ECM needs reprogrammed since the power was off for a long time? Perhaps the ECM lost the VIN?

 

[BK]

Sounds like the batteries are up there and ok.
Sorry, missed it that it cranks well and strong but no start...

If they were backwards, well , they'd be smoke and or blown fuses and burnt computers and you shouldn't see the 6vdc at the sensors, and I don't think the solenoid would have pulled in (but I could be wrong).

On my 99, after the battery has been disconnected, they say one should just reprogram the TPS , put the key to on (no start) and slowly depress the go pedal to the floor once and slowly bring back to it's resting spot. Then start, but never heard of a no start from not doing that.

Fuel drain back????
Try and prime the system at the vp44 inlet.

I was worried that if you welded on the frame w/o the battery cables shorted together, you may have induced a voltage and fried a computer.

 

[PLohr]

Excellent point about the TPS. That is worth a few minutes of time to try.



I found a procedure in the service manual for priming the system using the lift pump. But the lift pump will not run.

 

[BK]

Again, on my 99, to get the lift pump to run, I set the key to run, them bump the starter, and it sets the LP to run for 20sec , not sure if your year does the same, I would expect it to.....

Other than that, you could check the fsm / wiring diagram for your year, and take out the relay, and jump the output side of it to the battery (99% sure the positive is switched via the relay).
Or just take a couple of wires, pull the connector at the LP, and wire straight to the battery with a switch, make a cheater harness ( best to fuse it at the battery). Something I've been thinking of doing to make filter changes / repriming easier, vs the bump 20sec method.

 

[sag2]

I saw your other post where your thinking of replacing the ECM. Before you go to the expense, pull/push start it, or give it a shot of starting fluid (and heed all the normal warnings to avoid damage or injury) and see if it wants to stay running. Highly unlikely an ECM is bad.

 

[PLohr]

Thank you everyone for the suggestions and thank you for your time.



One of the ground connectors behind the driver side battery that connects to the body was not connected. It was hanging behind the battery - I should have checked more closely. Once I connected this ground, everything works ok.



Here I am thinking about the ECM and it turns out to be something simple. Note to self: check the simple things first.



Since I replaced both hubs, the ABS and brake lights were on for the first few minutes of driving. After those few minutes both lights turned off.



Thanks again everyone for your help.

 

[BK]

Great to hear..... it really sux when it doesn't start after a bunch of "un related work"... ...