Jump to content

'00 Silverado shutting off when engine is warm


Recommended Posts

Hello all,

 

I have a 2000 Chevy Silverado LT 5.3 Z71 with 270,000 miles. I really need some help/advice.

 

Recently I've been experiencing problems with my truck not starting when the engine is at operating temperature. For instance, I drive it 15 minutes, turn it off, run in a store, come back out and it won't start. Well, I say "start" but what I really mean is it will start and then immediately die. It will idle for about half a second around 300-400 rpms and just shut off. Usually what I will do is just keep trying to crank it and eventually after doing the same thing for about 20 keyturns, it will struggle to idle for maybe 10 seconds and then idle and run smoothly. I'm then able to drive home no problem. No noise or rattling or anything. The "Service Enginge Soon" light is always on regardless and has been since I got the truck 3 years ago.

 

Obviously I cannot do this forever as something is wrong and I don't want to end up stranded in some parking lot. Plus I know I'm wearing out the starter cranking it so many times. I live in South Carolina and yesterday it was around 100 degrees, so this problem will only get worse as the high temps make it harder for the oil to cool down.

 

After browsing the internet on and off for several weeks I'm convinced that is an oil pressure problem. I don't know if the engine is simply worn out and on its last leg where the only thing to do is rebuild the engine with new bearings and whatnot to get the proper oil pressure. But I also don't know if it's something else that I just don't know about. I've read that it could be the oil pump pickup tube or that running a thicker viscosity oil like 15w30 or 10w40 would help with the pressure. I just don't know and I'm hoping someone has experienced this and can offer a solution. I'm just wondering if I need to even go down this rabbithole or just try to trade it in and get a new car payment and a [peace of mind] warranty.

 

 

Few things:

1. I thought that maybe I had a bad Oil Pressure Sensor and that it was automatically shutting off the truck on its own. Since I didn't feel any vibrations or hear any noise, I figured why not just detach the sensor for now and see if the truck will stay running. I thought at first that this had worked but no, engine still shutting off.

2. I just changed the oil with 5 quarts of Mobil 1 5w30 and an STP oil filter. I also added one quart of Marvel Mystery Oil to it to help get out possible gunk. The oil level is in the proper range on the dipstick.

3. Last week I cleaned the Mass Air Flow sensor out with MAF cleaner in a spray can because the engine sounded to me like it couldn't breathe. However, I was able to rule that out b/c it did not fix the problem.

4. I was seeing a few articles on the problem being a small filter under the oil pressure sensor that clogs easily so that the sensor cannot get a correct pressure reading. However, I believe my truck doesn't have that filter. I think it was only on models from 2007 forward.

 

I will try to make a short video of exactly what it's doing and post it here in the next few days.

Thanks in advance for your help.

 

Link to comment
Share on other sites

Have the codes scanned. If the check engine light is on, there are diagnostic codes to be read. This will narrow down your search for problems greatly.

 

Most of the big chain autoparts stores will do this for free.

Link to comment
Share on other sites

From my experience the scan tools at an auto parts store are basic ones while you can try to find a shop that has a better tool that will be more specific and you might be able to find a shop that will do it for no charge. A local transmission shop has done that a couple times for me and I asked about scanning even if it has nothing to do with the trans and they said they would still do it either way even if I do get them to do anything to it. Try to find someone with a better scan tool than an auto parts store would have and scan for codes and then go from there.

Link to comment
Share on other sites

Ok quick update.

I took it down to Advance Auto and had them run the codes for free. This is the 3 codes they got:

 

P0300: Misfire

Possible Problems: ignition, spark plug, suppression ignition wire, distributor, distributor cap, distributor rotor,

 

P0449: Evaporative Emission Control System

Possible Problems: purge solenoid or vent solenoid

 

P0452: Emission System malfunction

Possible Problems: fuel tank pressure sensor and related connections

 

I will most likely take it somewhere tomorrow and pay for the more in-depth diagnostics but if anyone has any thoughts on the diagnosis, I'd love to hear it.

I am no longer overly concerned about oil pressure being the problem.

Link to comment
Share on other sites

Update: took it to Treadquarters, hooked it up to a diagnostic computer, determined it's the fuel pump. Seems to make the most sense. they quoted me almost $900, so I'm just going to fix it myself with new pump and relay. Will let you know.

Link to comment
Share on other sites

Archived

This topic is now archived and is closed to further replies.



×
×
  • Create New...

Important Information

By using this site, you agree to our Terms of Use.