98 Tahoe starts then shuts off

[adrenalin2k4]

I am working on a 1998 Tahoe 5.7l 2wd. I was approached to see what was wrong with this vehicle. The owner had several people working on it. Fuel pump, fuel filter, tune up, new computer and ignition. The vehicle will start up and then, shut right back off not even a second later. There is no trouble codes at all. I am thinking that it can possibly be a bad crank shaft position sensor. But, like I stated, there is no codes at all even with the old computer back in it. The Tahoe has over 200,000 miles on it. Any advice will be greatly appreciated. Thanks in advance.

[j cAT]

Originally Posted by adrenalin2k4

I am working on a 1998 Tahoe 5.7l 2wd. I was approached to see what was wrong with this vehicle. The owner had several people working on it. Fuel pump, fuel filter, tune up, new computer and ignition. The vehicle will start up and then, shut right back off not even a second later. There is no trouble codes at all. I am thinking that it can possibly be a bad crank shaft position sensor. But, like I stated, there is no codes at all even with the old computer back in it. The Tahoe has over 200,000 miles on it. Any advice will be greatly appreciated. Thanks in advance.

my guess is the security system ... have a automotive lock smith by pass the OEM security.. this is a common problem when they age. costs to much to repair so it is bypassed...

[777stickman]

In addition to a locksmith, a good car audio installer can do this also. Would be a place to start.

CKP could also be an issue. But since there are no DTC's it's hard to say.

What is the SECURITY light doing on start-up?