I’m sorry to bother y’all again I have the service [engin...

\*\*\*THE PHONE CALL REQUEST IS NOT FROM ME DIRECTLY\*\*\* \*\*\*PLEASE DON'T LET IT ANNOY YOU\*\*\* Please make sure you've listed the Year, Make, Model, Drivetrain and Engine information for your vehicle if you haven't already. Thank You for contacting JustAnswer! Hello I'm Bart. I am an ASE certified Master Technician with over 20 years experience in the Automotive Industry. I'm usually logged in 9-5 Mon-Fri Mountain Time Zone. I take lunch from 12-1p I know it can be frustrating having vehicle problems. I'll do my best to help you. Please understand that I don't know what your skill level is, what tools you have available and I can not physically see what you are doing. If it is more helpful the site automatically offers a premium phone call service where you can talk to me directly or another Expert may call you if you request it. You may accept or decline, but please understand that I may not be able to call right away as I may be helping another customer or researching information related to the problem you are having. If this is an electrical issue please a have voltmeter and 12 volt test lamp ready to use. I would also ask that you tell me what parts you have tried replacing to fix the problem. Doing so will help diagnose the issue faster. If there are any trouble codes please provide them. I'm reading the information you provided to the Mechanic's Assistant. I may request more information or provide an answer momentarily. Just a moment. Hello I'm Bart! I'll be helping you with your truck this evening. First, may I ask who I'm speaking with?

I’m Ruben by the way I haven’t tried anything not yet other says it’s mass flow sensor some says it’s my idle should I buy those parts

Hello Ruben! I'll do my best to help you with this. Could you give me the exact trouble code you've got here?

Here’s one code that reads

Here’s the second

Here’s the third

Here’s the fourth one I did all those

The service soon engine light comes onOthers think is my idle somethings it’s my mass flowI haven’t try anything else I take it to a shop they can’t tell me what happen to itI spend like 1400 on it it stalls and dies when you drive it when you stop it dies to

Okay thank you for that. You don't need a MASS AIR FLOW SENSOR for starters. What concerns me the most here is the P0304-that indicates a number 4 misfire. Most commonly would be an ignition misfire caused by a bad [spark plug](/topics-spark-plug-chevy/) or wire. Some other common issues on this vehicle are intake leaks, Stuck EGR valve or leaking fuel injector lines. I would need to see more live engine data using a more advanced scan tool to determine that for sure. If you could remove the number 4 spark plug, and send an image of the electrode to me, I may be able to determine what this issue is based on the color of the electrode. If it dark or wet soaked with gasoline, we can assume there is a lack or spark or compression. If it is red or really clean in color, we can assume there is a lack of fuel. The P0155 is a bad downstream oxygen sensor (the one after the [catalytic converter](/topics-catalytic-converter-chevy/)). You can replace that sensor to correct the code. That sensor typically will not cause drivability issues as it's main purpose to monitor the catalytic convertor operation. I hope this helps! Please let me know if you need anything else! **_<u>THANK YOU FOR USING JUSTANSWER!</u>_**

I don’t know what causes the truck to die when we drive it ima see if my brother can help tomorrow to get my number 4 spark plug outWe trying to see what causes the service engine soon light comes on to it dies when we drive it it dies when we stopTomorrow ima take it out it’s to late I hope you’ll be on tomorrow I really need help I spend $1400 I take the truck to the shops it stalls it dies when we drive it dies when we stop the service engine soon light comes on it’s reading codes I don’t know what to do at this point I don’t want to take it to a shop again I’m sorry Bart

No need to apologize! I'll do my best to help. I'll be on here tomorrow so just message me.

We switch the oxygen sensor and all the six spark plugs and wires I don’t what causes the truck to die when driving it and it dies when we stop at a traffic light I’m sooty Bart that I’m bothering you

Thanks for the update. Again, no need to apologize! The misfire being there could have damaged the catalytic converter. This can cause the [exhaust](/topics-exhaust-chevy/) to be restricted and the engine to load up with fuel. This can cause the vehicle to stall when at idle or stopped in gear.

That’s how come the service engine soon light comes on toAre do I need a knew engine toI’m sorry for asking to much questions

When my brother switch the spark plug we didn’t see any oil nor gas on them

Bart what causes it to stalk

Bart what makes the truck stalls

I'm sorry if not explaining this in a way you can understand it. I'll do my best to convey the information to you. Please let me know if you need anymore clarification. If there is an ignition misfire (indicated by the code P0304), the engine is only running on 5 cylinders. This reduces engine power and creates wasted fuel which exits the exhaust. The super heats the catalytic converter and can damage it. That can cause the exhaust to become restricted. This does not allow the engine to breathe adequately. So at lower RPM's like when you are stopped in gear at traffic light, this can cause the engine to stall, because it floods out, **especially** when the engine is at operating temperature because as the catalytic converter heats up and seals off the exhaust causing a stronger restriction. The engine is an air pump. If you can't get air out, air will not go in. If fuel is induced, the fire created in each cylinder in the engine will not burn efficiently, reducing engine power, because there is not enough air for the fire to burn. I suspect the exhaust system is plugged due to the bad cat from the misfire. You can **temporarily** disconnect and remove the upstream oxygen sensor (the one closest to the engine). This will create a new exhaust path for the engine to breathe. The truck will sound loud, but it will not hurt anything. You can test drive the truck and see if the issue is resolved or if the truck runs better. If it does, that means the catalytic converter is plugged. You will need to correct the number 4 misfire first. (p0304) by identifying the issue causing that misfire. Then you will need to replace the catalytic converter. Finally, replace the downstream o2 sensor (p0155). Furthermore, you should be getting a p0420 code indicating the cat is bad, but you will not because that downstream oxygen sensor is bad. That bad sensor is after the catalytic converter. It's main purpose is to send information back to the engine computer to tell it how the catalytic converter is operating. So if the sensor is bad, the computer will not know if the catalytic converter is bad. I hope this helps! Please let me know if there is anything else I can help you with. **_<u>THANK YOU FOR USING JUSTANSWER!</u>_**

My brother says that he will help me take the number 4 spark plug out

Okay great! Please let me know if I can help. **_<u>THANK YOU FOR USING JUSTANSWER!</u>_**

I still remember the last time my brother switch them out no gasoline on the old ones their still white I don’t know what happened know the truck dies when we drive it it dies when we stop the catalytic converter can be the cause of it

Yes. The catalytic converter can cause this issue.

I unplug the mass flow sensor it keeps on running the engine doesCan the catalytic converter keep the engine running while we unplug the mass flow sensor

Okay great. You've test driven the vehicle without the MAF plugged in and it runs normally?

It dies

I don’t know what to do

Please remove the upstream oxygen sensor and test drive the vehicle as advised.

Is it going to be the top close to the catalytic converter

Yes. The one between the engine and the converter. NOT the one after the converter.

I hope that works I keep on guessing I don’t want to take it to another shop cause they gonna charge a arm and a leg

Understood. **_<u>THANK YOU FOR USING JUSTANSWER!</u>_**

I read on the code p0155 is that the cause of stalling

I disagree with that. As stated before, the downstream O2 sensor monitors catalyst operation. It does not affect engine performance.

Could it be catalytic converterThat causes the truck to die while driving and stoppingShould I take it to get a diagnostic test

As stated before I suspect the catalytic converter is plugged. I would highly advise taking to a trusted shop and having them diagnose the issue.

What the spider injectors do

Here's a video explaining how that works. [https://www.youtube.com/watch?v=LrPrPUgNLf0](https://www.youtube.com/watch?v=LrPrPUgNLf0) **_<u>THANK YOU FOR USING JUSTANSWER!</u>_**