Engine starts and then stalls while driving?

you need to scan for codes to see what is wrong with system. You can try another key it may work otherwise it has to be scanned.

These guides can help

https://www.2carpros.com/articles/checking-a-service-engine-soon-or-check-engine-light-on-or-flashing

and

https://www.2carpros.com/articles/engine-stalls

Please run down these guides and report back.

A mechanic scanned it, no codes.
It just shows that the BCM is shutting off the injectors after two seconds. No clues as to why it does this.
The way I understand it passlock doesn't use a special key:
Passlock
This system allows starter operation, then kills the injectors one to two seconds after startup. This is a “Hall-Effect” system. The key cylinder housing has a small magnet that rotates past the Pass-lock sensor. The sensor is powered and detects the rotation. The voltage on the sensor then drops to a specified value (there are ten different values). There’s no pellet in the key. So basically this system is checking to see that a thief has not popped the lock cylinder to steal the vehicle. you have to perform a Power-train Control Module (PCM) relearn procedure (need a programming scan tool). The Pass-lock system was used on:

Buick
Skylark 96-98

Chevrolet
Cavalier 95-on
Impala 2000-on
Malibu 97-on
Monte Carlo 2000-on

Oldsmobile
Achieva 96-on
Cutlass 97-on
Intrigue 98-on

All GM trucks 98-0n

Hey Robert,

It sounds like the crankshaft angle sensor is going out, when this sensor fails the engine stalls and there can be no codes for it because the computer thinks the engine has stalled for other reasons, ie out of gas, fuel pump failure etc. On newer models the camshaft sensor will take over and the engine will still run, then the computer can see the failure, but not so in 2004.

Please try to replace the sensor here is an article on doing that.

https://www.2carpros.com/articles/crankshaft-angle-sensor-replacement

and video

https://youtu.be/sKo7xRWVNqY

Let me know

Best, Ken

It was the passlock sensor. Even though the dash light was acting like there was no passlock problem.

I did a 30 minute pass lock relearn and it started right up. Thanks for the help

My truck has the 6.0L Gasoline engine. About a month ago my truck started dying when the engine was warmed up. There was no check engine light. After discussing the problem with a mechanic, he suggested that it may be the fuel pump. Being that it is not uncommon for Chevy fuel pumps to go out at 80000 miles I took his advice and changed the pump. Once again the truck died when the engine warmed up. I thought that it may have been an electrical problem, so I had my battery and alternator checked. The battery was bad, however, this did not cure the problem. At this point I had no clue so I took it to the dealer. They told me that the ignition switch was bad and I had them change it. At last the truck ran. I drove the truck to and from work for a few weeks, about 16 miles per day with no problems. The engine did seem to miss just a little at an idle. This weekend I was taking a trip of about 200 miles. At almost exactly 100 miles and 75 miles per hour with the cruise control on the engine shut off and the battery light came on. Then it restarted on its own. I drove the next 10 miles with no problems. Then it started shutting off about every 5 miles, sometimes restarting and when it didn't I was able to shut the ignition off and restart with no problems. A local mechanic told me that I might have water in my fuel. I put the recommended conditioners in my tank and filled it the rest of the way up with High octane fuel. The problem did not reappear at slower speeds but after driving almost 100 miles once again the engine started the same problem. Any help would be greatly appreciated. I am desperate and broke from trying so many solutions. Thank You.

If the truck always starts right back up, I feel it is an electrical problem. Did the battery light come on while the engine was running? Also, has anyone checked the crank sensor to make sure it is clean and working properly? I have seen them go bad and act this way. The problem is there are so many sensors that can cause this type of problem, without the check engine light coming on, really makes it a guessing game. Even though the light hasn't come on, has anyone tried to scan the computer? Most parts stores will do it for free.

Let me know.

Thanks for your reply. The battery light did not come on while the engine was still running. The engine would quit, the light would come on and then the light would go back out if the engine restarted. As for reading the computer, I did have it read the first time this was happening. It did not return anything at that time, but I will try it again.

My 2000 Silverado did the same thing. Turned out to be some kind of crank sensoir as indicated above. Have not had a problem since changed out.

I was plowing my driveway, everything was fine, i was backing up and the engine stopped running. no bang ,clunk,noise of any kind, interior light works, head lights work, no radio, no dash instument, engine doesnt turn over with key,

Welcome to the forum. I'd have to check feed circuits to and from the ignition switch. As far as the starter circuit, you could check the circuits at the starter relay in the power distribution center. Voltage for the coil side of relay, goes hot with key in the crank position. Voltage to load/swith side of relay, is hot all the time.

I'm sorry it's a 1994 chev trk. i dont know if it matters,,, where abouts is the power distribution center on this truck? On fender by battery?

Hi, thanks for the donation. The model year does make a difference, there is no starter relay for the 94. looked at 94 chevy truck K1500 gasoline. Use a testlite, check voltage to ignition switch, red wires, hot all the time. As far as the starter, the purple wire, right side of switch, goes hot with key in the start position. There are other tests for the starter,but, right now, I'd check the circuits at the switch.

I have the truck listed above 5 speed.
Was driving and the truck just shut off no warning had been running great. Well I checked and I have no spark the fuel pump runs when key is turned on and do have fuel PSI the cap rotor plugs and wires have been replaced about 2 weeks ago just for preventive maintenance. So a friend told me it might be the crank sensor so I replaced it but still crank but no start . I checked and I have power 12 volts to the module and coil but no spark at plug wire or no spark at coil . Any ideas would help . Thank you

It is most likely the ignition module, but could also be the cam sensor.

Rich

I have tried a ignition module, but I will try a cam sensor and let you know. Thank you very much.

You are welcome. You can also make sure you have your 5 volt reference at the cam and crank sensors. If either one is missing it the sensor wont function and leave you with no spark.

Rich

Thanks. I have checked the crank sensor and it seams to be working . Can I check the cam sensor the way I did the crank sensor or is it checked a different way?

Nope, its the same way. One side is the 5 volt reference and the other is a pulse signal same as crank.

Okay, thank you. I’ll check it and let you know. Thanks again.

I have seen the crankshaft sensor cause this issue here is a video to help change it out.

https://youtu.be/sKo7xRWVNqY

Please let us know what happens.

Ok Here We Go I Have A 2004 Silverado With The 5.3 It Is Fly By Wire Throtle Body. The Truck Has Ported Heads, Headers, 4.10 Gears After Market Cam It Had The GM HD Transmition 4l60e In It I Changed The Throttle Body From A 75mm To A 80mm It Ran Fine. Then The Tranny Blew Up It Broke The Output Shaft In Half. So I Took It To The Transmition Shop They Built Me A Transmition With The Shift Kit 5 Planet Gears The Whole 9 Yards. The Converter Was Supost To Be A 2,700 Stall So I Got The Truck Back And The Truck Lacked Power And Was Not Shifting Right So I Bring The Truck Back To The Trans Shop They Tell Me The Reverse Gears Burned Up They Fix The Prob I Tell Them The Converter Is Not Right Does Not Feel Like A Stall Conv. The Converter Is The Same Housing I Had In The Blown Up Trans. So They Change The Converter It Looks Like The Same Sise As The Old One. The Truck Has A Clunking Noise When It Is At Idle And When Stoped And When Restarted Like A Shuter In The FlorBoard Area And Is Even Slower Than The Last Time. So I Bring It Back, The Teck Goes On A Test Drive With Me And Tells Me That He Cant Feel Nuthing Wrong So We Stop At A Light And I Tell Him That I Will Get On It One More Time, When The Light Turns Green I Start To Go And The Truck Just Reevs Up To 3000rpm And Wont Go!! So We Tow It Back. They Tell Me The Pump Gear Burned Up So They Replace It. The Converter Is Still Not Staling So I Get My Owne From A Aftermarket Dealer It Is A 9" 2,700 Stall Lock Up Converter. The Converter Noise Goes Away The Tranny Shop Fixes The Tranny I Get The Truck Back And The Stall Is Great But The Truck Surges And Some Times Dies When Applying The Breaks Even When I Coast To A StopThe Tuck Dies After The Lasd Down Shift ( It Does Not Die When It Is Cold)
I Have The Cooling Fan On The DARLE Two Coar Trans Cooler So It Is Not Geting Hot. And When At Speeds Of 30mph Or Greator When I FLOOR The Gas The Truck Starts To Rev Up And Just Cuts All The Way Out For A Split Second Then Catches And Away It Goes Then When I Reach High Speeds And RPM (The Rev Limiter Is Deleted) The Truck Cuts To Like 4cylinders And Says Reduced Engine Power And The Check Eng Light Goes On And The Coad Says The Throttle Pos Is Not Actual. But If I Dont Tromp On It All The Other Problems Are There With No Coads. I Have Checked The Fuell Press. It Is Fine. And When I Rev The Truck Up Slowley It Will Surge Several Times UP DOWN And Die If I Let Off The Gas. And Around 3,000 To 4,000 rpm In Neutral When Pushing The Gas Verry Slowley Down The Rpm Stays The Same Even When Pushing For A Short Moment. HEEELP!!!!!

problem is either in the throttle body or the gas pedal. i just had a trailblazer with the same code and i flipped the coin and it landed on gas pedal and that fixed it.

After starting my truck from cold or after 20 minutes of cool down, I drive less than few hundred yards and apply brakes to stop or turn, engine runs rough and then dies. Restarts immediately, but it dies again if I let off throttle, while applying brakes. Battery light comes on when engine dies like it should. Please help. I have added an AEM cold air intake and an Air Raid throttle body spacer. No other mods. Ran different brands of octane booster and higher octane fuel through system and seems to run rougher. Thank you, Chris

disconnect your maf sensor and see what happends. Do you have a check engine light on?

No, check engine light as of yet. What are the possible issues that may arise if the maf is disconnected?

nothing, just your check engine light will come on. if the MAF is the problem, with it disconnected you should have plenty of power and no stalling

I bought some CRC brand MAF Cleaner and sprayed the sensor, slight improvement. Still stalls, but runs smoother. Have to spend to get it fixed right. Always go cheap first. Thank you for the tips and advice. Wiley coyote!

try to disconnect it first before you spray anything into it

My truck has an intermittent issue. Sometimes it's fine sometimes when I come to a stop it will shut off. Once it shuts off when I restart the truck it will shut off in seconds if I don't give it gas and then when I left off the gas it will shut off again if stopped for more then 5 seconds.

This sounds like an idle air control issue. Here is a bunch of info on this and let me know if you have questions:

https://www.2carpros.com/articles/how-to-replace-an-idle-speed-control-motor-iac

https://www.2carpros.com/articles/idle-air-control-valve-service

Basically you holding the throttle open is compensating for the IAC being stuck closed or not open enough. I would suggest removing it and at least cleaning it to see if that makes a difference.

Let me know what you find with this and we can go from there. Thanks

Hello, I'm Danny.

I believe it could a possibility of 2 things. First is a weak,faulty, or failing fuel pump that is not providing enough fuel pressure intermittently.If you don't have access to a fuel pressure tester most auto parts stores have a tool loaner program and can rent you one. Here is a tutorial showing what is involved:

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

The fuel pressure specification for your truck is 55-62 p.s.i. with the key on engine off.

Secondly, Which I'm more leaning towards is the IAC- idle air control valve.Makes a little more sense since your issue always seems to be happening at idle. Here are 2 tutorials for you to view relating to the idle air control valve:

https://www.2carpros.com/articles/idle-air-control-valve-service

https://www.2carpros.com/articles/how-to-replace-an-idle-speed-control-motor-iac

Let me know if you have any further questions on this issue.Hope this helps and thanks for using 2CarPros.

So I replaced the throttle body because the IAC is one part. The truck idles fine now no issues when stopped but the dang thing has now shut off twice but only when making a right turn and it only shuts off for split second then runs fine.

This sounds like a possible fuel issue. I have found that at times making turns the fuel pump will drop slightly and the engine will cut off. Then run normally except for these random times. So this sounds like Danny's other suggestion so let's check fuel pressure when this is acting up. I would just hook up the gauge and tape it to the windshield so you can drive around with it hooked up and monitor it whenever it acts up.

Let us know what you find and we can go from there. Thanks

Hello again.

Just curious to know if you've been able to test the fuel pressure to see if it's a possible issue with this symptom.I'm my prior post I included your fuel pressure specification which is 55-62 PSI. for your truck.Keep us updated. We're here to help.Thanks again for using 2CarPros.

Danny-

Chevy Silverado 2004 8.1 gas engine. Ran well until battery went dead as I left something on in the cab, recharged both batteries and they are staying charged, truck starts right up, but only stays running for 3-5 seconds then shuts off. Checked out alternator working good, high output. noticed that the charging guage does not advance up however on the dash. needle moves, but does not go up to 12 or 14v. Don't know what to check next?

there is a fusible llink that runs off the generator that may be bad. there also is afuse holder near the right battery and a auxillary relay at right rear of eng compartment. put a volt gauge on your battery and see how may volts it gets while running at about 1500 rpm. Also with 8.1L they tend to loosen the intake bolts so see if they will tighten. but don't be a gorilla as they will break they aren't that big.

I own a 2004 chevy silverado 1500 with a 5.3 liter eng. Recently the eng light came on and it started running really rough like it was going to die. It not only runs rough at idle but also in gear or hesitates when i excelerate from a stop. Ive done countless diagnostics, only to come up with multiple problems it could be. One was a possible blown intake gasket which i replaced and the truck ran fine for a little bit then the eng light came on and started the same thing. I also bought the 2 before cat oxygen sensors but havent installed the yet. Can anyone tell me what to look for or try from here?

Let's start with what are the exact code number's you have?If you tell me those i can help you out.

P0131, p0171, p0300 these are the codes that i have.
Thank You, Gary

These are the codes that i have P0131,P0171,P0300
Thanks, Gary