Red lighting bolt - Truck stalled and died

[Jason Welch]

Long story short I was driving and got the flashing ETC. Truck went to idle fell on its faced knocked a bunch and shut off. AT this point no CEL. Towed home tried to start and it started but super low idle and sounded like timing was way off. A lot of knocking and pinging. This time I got a CEL. P2172.

I decided I need to test 5v ref at the sensors. The MAP, Crank pos, Cam pos, all have 4.9v on two wires no just one. I don't have a schematic but I believe this is incorrect. Grounds are good but the other two wires on the above sensors all have 4.9v when shooting to ground with the sensors disconnected.

I believe I have a short on the signal path somewhere.

The question is...Are there any more 3 wire sensors I need to check to see if they are the cause of the short?

New Update...Disconnected PCM and shot signal wire to Ref wires and there is not a short. Either the PCM supplies voltage on the signal wire during Key On Engine Off or there is a short in the PCM.

Furthermore, when truck starts in open loop it runs as soon as it switches to close loop the short trim drops to -15% for both bank 1 and bank 2 and truck dies. I assume this means the truck is sensing it is in a rich condition and trying to lean out.

 

[Jason Welch]

I have ruled out a short to the signal wires. The truck will not start anymore it is really hot out. (Maybe I have an ambient temp issue)??? It seems to be extremely rich and timing seems far off at idle. I was connected to the MAP on the last start and watch the voltage drop as vacuum was created the more throttle I gave it the lower the voltage read. I don't really know where to go from here as I cant get it started to test other sensors. Any help would be appreciated.
The MAP is new and so is the CAM sensor.

Started thinking that maybe the STFT1 and STFT2 are acting appropriately and I do have a rich condition. I decided to pull a plug to check it out.

I'm at a loss right now. Is there a procedure for troubleshooting the PCM. The current codes after running it today are P0300, P0303.

UPDATE: Ran it at idle for 25 mins and then it finally died. Multiple misfires with erratic idle up to 1500 back down to 500 RPM. Threw a bunch of codes. Also go to monitor close loop vs open loop. still had moments when stf1 and stf2 would go to -33%. I was more concerned with the 02 sensors not moving up and down alot. Bank1 02 stayed stedy alot while bank 2 moved and then it would switch. nothing seemed right.

P1DD2
P0020
P0175
P0172
P2097
P2099
P2172
P0300

 

[huntergreen]

Have you checked your battery. Some times they start craping out long before they should. Low voltage from the battery causes funky things to happen.

 

[tidefan1967]

How many miles are on the truck?

 

[chri5k]

You have a number of codes there. I would look them all up and write down where they point. Often you will see a pattern or a point of intersection for the codes. That is the best place to start with repairs. Based on the sooty plugs and engine running description, something is telling the computer the mixture is too lean so it is dumping more fuel in there in an attempt to richen it up. With your list of trouble code descriptions you can then narrow down the likely culprit for examination.

 

[Jason Welch]

48,000 miles on the truck.

 

[Tach_tech]

What made you suspect the 5V reference when the first code you got P2172 is for high airflow/vacuum leak. A issue with the 5V reference circuit can cause that code but it’s not very common.

I would be checking for vacuum leaks before I start going to far down a rabbit hole. Also check the throttle body for any obstructions or if it’s extremely dirty.

 

[Jason Welch]

I figured some sensor was sending back wrong info. causing the issues. I have looked for a vacuum leak but couldn't find anything. I;ll have to try with some carb cleaner today. Throttle body is not gummed up or anything. Also I can read the vacuum value when running but haven't recorded it. What should the vacuum be?

One thing i didn't mention previously is last night when it was idling poorly for 20 ish minutes I noticed the traction control warning light stayed illuminated the whole time. This is not normal I have only ever seen it come one if sliding in the rain.

On a side note I also put 37's on the truck last Friday and put about 300 miles on them before the truck crapped out. I don;t know if this has anything to do with whats going on.

 

[Tach_tech]

It could also be an issue with the throttle body as well. The traction control light can come on when there are throttle body issues. The code it will usually set is a torque request signal denied.

A broken valve spring can cause this as well as an exhaust restriction.

I wouldn’t be going after electrical issues till I was sure there was no other mechanical faults.

 

[RamCares]

I have ruled out a short to the signal wires. The truck will not start anymore it is really hot out. (Maybe I have an ambient temp issue)??? It seems to be extremely rich and timing seems far off at idle. I was connected to the MAP on the last start and watch the voltage drop as vacuum was created the more throttle I gave it the lower the voltage read. I don't really know where to go from here as I cant get it started to test other sensors. Any help would be appreciated.
The MAP is new and so is the CAM sensor.

Started thinking that maybe the STFT1 and STFT2 are acting appropriately and I do have a rich condition. I decided to pull a plug to check it out.

View attachment 205171 I'm at a loss right now. Is there a procedure for troubleshooting the PCM. The current codes after running it today are P0300, P0303.

UPDATE: Ran it at idle for 25 mins and then it finally died. Multiple misfires with erratic idle up to 1500 back down to 500 RPM. Threw a bunch of codes. Also go to monitor close loop vs open loop. still had moments when stf1 and stf2 would go to -33%. I was more concerned with the 02 sensors not moving up and down alot. Bank1 02 stayed stedy alot while bank 2 moved and then it would switch. nothing seemed right.

P1DD2
P0020
P0175
P0172
P2097
P2099
P2172
P0300

Hi @Jason Welch - If at any point this is something you have to address with your dealer, please be sure to follow up with us via private message. We would be happy to escalate a case on your behalf for further support through that process.

Mark
RamCares

 

[Jason Welch]

So yesterday I search and search for a vacuum leak and found nothing. This morning I decided to put a fresh battery in and clear the faults. The weird thing is all the faults cleared but the traction control light stayed. When I started it with a fresh battery it fired up normal and ran normal for about 30 seconds. I had my torque app running on my phone to monitor everything and all looked good for those 30 seconds and then everything start going down hill again. I shut the truck off check codes and nothing popped. Then I turned the key on and as soon as I went to start my torque app said "caution icing conditions". This is the first time I had the volume up on the app and I still have no check engine light just the traction control light on as if the truck thinks its sliding or something.

 

[Tach_tech]

You’re gonna need an actual scan tool to retrieve all the codes unfortunately. Traction control light being on isn’t just for sliding etc. The light flashes when the esp system is activated. Light on solid means there is a fault. Also would be a good idea to monitor misfires but again you’ll need a good scan tool to do that. The torque app can only retrieve basic P codes, and possibly not all of them.

 

[Jason Welch]

Yep. I agree. My buddy is coming over Monday so we can read the codes within the ABS module and also watch live misfire count to determine what is actually going on.

 

[Jason Welch]

Well its time for an update. Think we have it narrowed down to the throttle body. The min voltage on tps2 is 4.49 which equates to 89%.

 

[Tach_tech]

That’s actually normal. There are 2 TPS sensors, and they mirror each other for sensor redundancy.

• TPS 1 voltage starts low, approximately 0.5 volts at closed throttle, and increases to approximately 4.5 volts at wide open throttle.
• TPS 2 voltage starts high, approximately 4.3 volts at closed throttle, and decreases to approximately 0.7 volts at wide open throttle.

 

[Jason Welch]

Got it...I plugged back in and watch the two and what you said makes sense. So where should I go from here for troubleshooting.

Truck hardly starts, idle is super low and it is definitely running super rich. Short term trims for each bank make there way to -32 and that about the moment the truck dies completely. The only DTC currently present is the P0300 - random or multiple cylinder misfire.

 

[Jason Welch]

Well i guess its time to pull the valve covers and make sure this isn't anything mechanical broken. I ran it this morning so I could capture the codes with freeze frame data. Now the tuck is smoking like crazy and smells like un burnt gas.

Here is the report if you guys see anything off. It is a .pdf with the codes and the freeze frame data. There are some codes present that say permanent next to them that I cannot clear. I am pretty sure I set those codes while I was shooting voltages with the key on and sensors unplugged.

 

[BobSacomano]

Following with interest. Good luck.

 

[Jason Welch]

Well....this sucks.

 

[BobSacomano]

View attachment 206175 View attachment 206176 Well....this sucks.