Need Help Running Out of Ideas [99 1500 4x4 starts, then stalls]

[F-Body_Hottie]

I have a 1999 Z71 1500 Silverado. recently it has started to give me problems. Every now and then when i go to start it, it starts right up then stalls. It has no problems turning over. If i walk away and leave it alone for like 30 mins it will usually start right up and run great. It also runs through errors in the message center, things such as service 4 wheel drive, low fuel, the battery light, and the security light. I thought it was this aftermarket security system so i disconnected it, but the problem continued, then i thought that i might have a dead cell in the battery, i went and bought a new battery, no fix. I read that improperly connected electric start security systems can cause damage to the computer. I just wanted to get any other advice before i went and bought a computer.

Thanks a bunch,
Kat

[Swanny007]

Are there any trouble codes (is the Check Engine light on)?

My brother-in-law had a GMC about that year. He had starting problems for years, and he'd sit in his truck waiting, etc. Very similar symtoms. He eventually took it to the GM dealership and they flashed the PCM. Problem solved.

If there are no DTC's you might want to bite the bullet and take it to the pros. Otherwise give us the codes or look at REMOVED BY MODERATOR

[F-Body_Hottie]

Nope, the service engine light hasnt come on in years, the ABS is on but i figured i had a bad sensor somewhere and was not to worried about that, i can pick a used computer for 45 shipped i just dont want to spend money on something that does not need to be replaced. I have not yet took it to a dealership or mechanic, but i most likley will soon

[kahjdh]

do an alternator test before you do anything drastic.

[F-Body_Hottie]

But my Alternator isnt giving me any problems, the truck starts right up, then dies after like 2 secs. I put it on a code reader the other day and nothing came up. It hasnt been acting up the past couple days. It just does it every now and then =[

[kahjdh]

Sounds like a computer, bummer

[rockwood84]

check the throttle body for build up on the plate or worn plate guides, clean the iac ,check the tps and see if it is still in the notch,i've seen the notch key break off and sensor move.

[j cAT]

Originally Posted by F-Body_Hottie

But my Alternator isnt giving me any problems, the truck starts right up, then dies after like 2 secs. I put it on a code reader the other day and nothing came up. It hasnt been acting up the past couple days. It just does it every now and then =[

this sounds like empty gas tank or a restricted fuel filter....every 30,000mi replace fuel filter,,,

[rhandwor]

Have you checked fuel pressure the pressure regulator might be on the low side. Origional equipment can be adjusted somewhat.

[waitingforcolumbus]

My co-workers 99 did this. We read on this forum it could be the fuel pressure regulator. The check was to remove the vacumm line from the regulator and if gas came out of the hose the regulator was bad. Gas dripped out, he replaced the regulator and the truck has started fine since. It's easy and free to check anyway.

[rockwood84]

a friend of mine had something like that on his '02 silverado 8.1 .it would run fine then it would just die then run fine. we found out later that this was the cranksensor and it got to where it would do it more and more.the cranksensor on an 8.1 is pretty rough to get to .what size motor yours have 5.7? his did the security light also and if he let it cool off a little while it would crank and run till the sensor got hot again.also when the sensor first started to act up it didn't set any codes off except a misfire code or idle below threshold. i think the cranksensor was around $95.00 but that 8.1 been burning gas since we put a new cranksensor in. his old cranksensor was cracked on the end .

[F-Body_Hottie]

Thanks abunch guys, ill try the fuel pressure and tommorow ill check my cranksensor. =]

[j cAT]

Originally Posted by F-Body_Hottie

Thanks abunch guys, ill try the fuel pressure and tommorow ill check my cranksensor. =]

the other componet to check is the resistance of the ECT sensor cold...then when engine is hot....if the resistance is incorrect it may tell computer that the engine is hot when the engine is cold and this will cause your problem as the injectors will not be turned on long enough to allow sufficient gas to flow ..common problem...

[ukrkoz]

when you install the remote start system, OEM security passlock system supposed to be disaBLED. THERE'S A SPECIFIC PROCEDURE FOR THIS, OR THE SECURITY SYSTEM CAN DECIDE SHUTTING DOWN VITAL SYSTEMS TO "PREVENT THEFT".
sorry, my finger slipped and hit caps, but it sort of looks good, so i let it be. my typing speed is horrible. lazy am i.
anyways, try this:

*****, i asked your question in some other places. so far, i had one answer: try "relearn" process. they said to insert the key in, turn the accessories on, let the security light do what it does, and try to start the engine. if it starts and dies, just let it sit like this, without removing the key or doing anything else, for as long as it takes for the light to reflash and go away. they said it might take up to 30 minutes for ecu to relearn the situation.

also this might help:
http://chevroletforum.com/m_1839/tm.htm

a chevy is a chevy, should be the same for any car.

[crash_1333]

try repalcing this part... The Ignitan Controll Moduel cost about $10 4 wires plug in that would also cause your truck do that my dad and my friend had the same prob u r and that was the cause