does not start sometimes

If the security light is flashing then the alarm is stopping it from starting. If the light is not flashing then I would say it is the fuel pump that is causing the problem. Here are a few guides that we help us get started finding out the problem.

https://www.2carpros.com/articles/how-to-check-fuel-system-pressure-and-regulator

and

https://www.2carpros.com/articles/car-cranks-but-wont-start

and

https://www.2carpros.com/articles/how-to-reset-a-security-system

Please run some tests and get back to us so we can keep helping you.

Cheers, Ken

The fuel pump was replaced and they had the wrong adapter so we changed that out. Went to start it and it won't start. Checked all the fuses and none were blown, tried bleeding air from the lines under the hood no gas came through when turning the key to start several times. Went back and took the tank down rechecked the lines to make sure they were connected good no gas was in the lines when I took them apart to check. I also switched the relay from the AC to the fuel pump relay just to check that and it made no differnce. You can hear the pump run when the key is in start position.Any idea what the problem may be? Thank you!
~Tina

is the pump in right and not installed backwards?

also maybe the sock is plugged or enough gas in tank? should have at lest 5 gallons

Yes it is installed correctly and there is more than 5gallons in the tank.

without really looking at this I can't give you a definitive answer. Unless the wires broke going to the pump but you said you hear it running. Only thing it would leave is a blocked line. can you blow air back through it? the only thing I can think of is an internal leak or the check valve isn't any good

I took the instrument cluster out and fixed the speedometer put everything back together it wants to start it just is not completing the start. I'm not sure what to do I replaced the battery cause it had a bad cell but still won't run what do you think it is I also checked the fuses there are none burnt out.

anytime battery is disconnected your may need to reset security system see pic.

Electrical problem
2003 Chevy Suburban V8 Four Wheel Drive Automatic 180000 miles

3 mounts ago I parked my truck at work, after work it would not start ( I had a 1/4 tank of gas) I add 3 gal of gas to the tank and it cranked (yes the fuel gage works).

A few weeks later it did the same thing, I add a couple gal of gas to the tank and it cranked.

As long as I keep half a tank of gas I have no problem with starting.

Now I am having intermittent a loss of power and cutting off with more than a 1/2 tank of gas (sometime with a full tank of fuel).

It seems to happen more when the vehicle has set for a time idling, then again I drove 200 miles and it happened when I got off the interstate.

I have replaced the fuel filter and swapped out the f/pmp relay.

I have had the same locking fuel cap on the vehicle for 3 years.

Welcome to the forum, next time you have a problem, use a gage and check fuel pressure. I glanced through some bulletins on your vehicle, the only thing that caught my attention was improper fuel gage readings?

Transmission problem
2003 Chevy Suburban V8 Four Wheel Drive Automatic

Just had transmission rebult. so I Put it back in and car wont start. It will start if I cross starter. Is there a reset on something that I dont know about???

Did you connect the park and neutral position switch?

yes and adjusted shift cable where shift indicator lines up in every position correctly justed stopped by chevy dealer there is no restet

Do you have power to the park/neutral position switch in Park position -if not best check and test the ignition switch

Engine Performance problem
2003 Chevy Suburban V8 Two Wheel Drive Automatic

I let my suburban set for 1 week in cold weather (20 degrees) with very litle gas. Tried to start it. Fuel pump did pressure noise no problem. Engine turns over but won't start. Added gas up to 1/4 tank but no luck. Ideas?

Thank you
BJ

Hi:
You need to check for two things, fuel pressure and spark to the plugs. One will most likely be missing.

Let me know what you find.

Joe

Electrical problem
2003 Chevy Suburban V8 Four Wheel Drive Automatic 125000 miles
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Daughter ran out of gas. I put gas in it and now it won't start. NO problems prior to this. Read manuel about fuses and found that the ignition and heated seats are on the same fuse, the heated seats do NOT work so I started looking at fuses and could not find a problem,although some of the fuses are in a clusters and could not see if there was a problem with some.

Thanks
TJ

ahhh, running a vehicle out of fuel. happens to all of us!

when a vehicle is ran out of fuel it usually causes the fuel pump to go out, especially if its original and has accumulated a lot of miles or is used to being ran around with just vapors in the tank. there is where im sure your problem is.

Transmission problem
2003 Chevy Suburban V8 Four Wheel Drive Automatic

I JUST R & R'D MY TRANS IN OUR 2003 SUBURBAN W/ USED JASPER TRANS AND NOW IT WONT START.I SAW WHERE BRANDON HAD ASKED THE SAME ? AND WAS WONDERING WHAT HIS FINAL ANSWER WAS.PLEASE LET ME KNOW ASAP AS I HAVE THIS ONE SOLD.
DID I MENTION THAT THIS IS THE 2ND TRANS FOR THIS AUTO,AND I HAVE HAD TO PUT (2 TRANSFER CASES AND (2) REAR ENDS IN MY 2002 2500 HD P/U

I JUST R & R'D MY TRANS IN OUR 2003 SUBURBAN W/ USED JASPER TRANS AND NOW IT WONT START

Is it cranking over? if not could be the park and neutral switch when you put it back together-now if its cranking over and wil no start could be fuel or spark problem

2003 Chevy Sub 1500 4WD/Flex Fuel - Truck isn't starting up on first crank, and seems like gas is slow to move up the system. Just had the Fuel Pressure Reg changed 2 weeks ago, but its still takes 2 or 3 cranks to start up. Now the check eng light is coming on and saying "reduced engine power" and will not go over 20mph - if I let it set after that happens for about 20min, it starts up and runs fine again - ANY CLUE ?

is it doing it when cold or hot?

started over the winter, so when its cold I guess

seems harder to start though when its warmer outside.

also its very slow to start, almost as if the battery is dying, but its at 95% and amp jump to 14 on the meter straight up.

maybe you should get your starter checked out. it may be drawing too many amps putting to big a load on battery.

car died w/driving took to personal mec scaned w/prolink will not communicate w/computer in car

Do any lights in the dash work or headlights etc? Have you checked fuel pressure?

yes i hooked my pro link to obd port no communications withecm

ok...Im not really concerned with codes. Need to know if you are getting fuel pressure, spark, or charging?

no fuel pressure no spark either

This morning my wife went to take the little one to school and she said the burb wouldn't start. No clicking, no lights nothing. She went to call her Grandmother for a ride, got back in the truck and tried a few more times. Then she said she heard a "clunk" and everything just started working. Truck started and everything. Any ideas?

1st thing 1st ..... do a voltage drop test on all pwr and grds ..when u crank ur battery better has 10.5 volt during cranking..if not start testing battery and chking all pwr and grd ...good luck

Does the engine turn over when trying to start it? You say your scan tool will not communicate...hmm... is your cigarette lighter fuse good?

thi is a start simple job and check all of thelectrical first , remove the vateery cables and look for corrosion if there is you can clean them and the terminal with a small wire brush , check there and let us know what happens

thanks , jim

oh and if you are happy with the info please leave some feedback we all donate out time here helping people for free

It turned out to be a battery cable and a poor connection. Thank you all.

We've got the same problem I have been reading about in this forum. Sometimes our 2003 Suburban will not start when the fuel gauge reads between a quarter and half a tank. When we pour in 2-4 gallons it fires right up. The dealer indicates it's the fuel pump.
Does the fuel pump have a fuel level sensor to shut the pump off at a predetermined level? If there is a fuel level sensor, can it be replaced separately from the fuel pump?

I have had a 1997 C1500 and presently have a 2000 C3500. On both trucks, the gas gauge quit working. I was able to buy the fuel level sensor by itself.....without buying the entire fuel sending unit. Both times it only cost me about $110.00 plus tax.

I was advised to replace the bcm on my 2003 suburban. It kept saying rear access door open and the interior lights would not go out. The alarm will also go off with no reason. The rear gate and window sensors and latches are fine. So.. When I replaced the bcm my truck will not start, interior lights do not work or the radio and a code says service 4 wheel drive. Do I have to program the new bcm or something? The old part number is 151198116. The new ac delco part that covers this is now 10367690 which is not working. Any help would be great! Thanks for your time!!

If you put a brand new bcm in it has to be programed and you have to relearn the pass lock for it to start after the programing.