cold drivability

[RamDiver]

I can confirm that the problem started a month or so before the plug change.
The PCV valve was clean and rattled when I gave it a shake.
In regards to the plugs, I checked the gap on all of them prior to installation. I'm kind of old school that way.
I looked at the adaptives and they flip back and forth between about +2 and -4 on both sides. On a cold soak overnight, both the intake air temp and coolant temp read the same.

Excellent work on confirming the gap on the plugs.

And did you inspect the vacuum lines to/from the PCV valve for any damage?

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[Hagar1]

Excellent work on confirming the gap on the plugs.

And did you inspect the vacuum lines to/from the PCV valve for any damage?

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Yes, I've checked the vacuum line. My biggest problem is that everything that I check seems to be within the "normal" range. There is clearly some "little" thing that I am missing.
I would not install a spark plug without verifying the gap. That one can "burn" a person right quickly.

 

[RamDiver]

Have you inspected and tested the sparkplug wires?

How To Test Spark Plug Wires (4 Methods + 2 FAQs)

Discover how to test spark plug wires using four popular methods and get answers to some related questions.

www.repairsmith.com

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[Tominator223]

Could be a lazy 02 sensor.

 

[Dusty]

Does the engine idle okay?

Could be a lot of things, but if you have access to a good diagnostic tool, I would first check for fuel delivery (fuel pressure) and camshaft position. In fact, I think in that model year Crankshaft Position Sensors could be a problem.

Regards,
Dusty
2019 Ram 1500 Billet Silver Laramie Quad Cab 2WD, 5.7 Hemi, 8HP75, 3.21 axle, 33-gallon fuel tank, factory dual exhaust, 18” wheels. Build Date: 3 June 2018. Now at 96271 miles.

 

[Hagar1]

Have you inspected and tested the sparkplug wires?

How To Test Spark Plug Wires (4 Methods + 2 FAQs)

Discover how to test spark plug wires using four popular methods and get answers to some related questions.

www.repairsmith.com

.

This one has coil on plug.

 

[Hagar1]

I have a 2012 Ram 1500 with an interesting problem, well for me anyway.
It starts normally and well cold or hot. But with cold start, and starting to drive, it has almost no power and there feels to be a slight miss. If it was a carburetted vehicle, I would think that the power valve was stuck closed. Once it warms up it appears to run fine. The other interesting part is that the fuel economy dropped from 21 -22 MPG on the highway down to 14 MPG highway.
The spark plugs were recently replaced with no improvement. Air filter is clean.
Any ideas much appreciated.

So, this morning, before starting the truck, I checked coolant temp sensor reading, Intake Air temp and battery temp are all within one degree. CTS and IAT were both at 18C and a voltage of 3.87 Volts. Battery was at 19C and voltage was 2.86 Volts.

 

[Bigskyroadglide]

I have a 2012 Ram 1500 with an interesting problem, well for me anyway.
It starts normally and well cold or hot. But with cold start, and starting to drive, it has almost no power and there feels to be a slight miss. If it was a carburetted vehicle, I would think that the power valve was stuck closed. Once it warms up it appears to run fine. The other interesting part is that the fuel economy dropped from 21 -22 MPG on the highway down to 14 MPG highway.
The spark plugs were recently replaced with no improvement. Air filter is clean.
Any ideas much appreciated.

Have you checked the intake manifold bolts. They have been known to loosen up over time. They tighten into plastic, so don't go gorilla on them. Torque specs are like 96 to 108 inch lbs or about 8 ft lbs. If one is loose and then when the engine get warm and issues subside, one could be loose allowing air to get into the system. Food for thought

 

[NCRaineman]

I would definitely check for intake leaks and check those O2 sensors too. If your fuel mileage has crashed you're getting too much air (or a sensor thinks you are) and the computer is dumping fuel to compensate.

 

[Hagar1]

I would definitely check for intake leaks and check those O2 sensors too. If your fuel mileage has crashed you're getting too much air (or a sensor thinks you are) and the computer is dumping fuel to compensate.

We had the intake off a couple of weeks ago and my buddy put it back on. I relied on him to torque it.
The O2 sensors seem to be switching normally. Now, here is a twist ..... when 'cool' prior to getting up to operating temp I noticed what I think might be an anomaly. I was going up the hill that I usually encounter the problem and I observed the spark retard was displaying 13.5 degrees which coincided with the sluggish engine. I was driving gently at the time. Detonation sensors showed an increase in voltage as well. As the engine came up to full operating temps, the spark retard problem diminished to somewhere in the neighborhood of 0.5 degree retard.
Gasoline problem????

 

[Hagar1]

Just finished testing the alcohol content of my fuel supply, it tested at 3% alcohol.

 

[Hardracer]

Man,I was gonna guess tranny all the way...up until you said it backfired..bet one of these fellas will nail it for ya though

 

[Hagar1]

Man,I was gonna guess tranny all the way...up until you said it backfired..bet one of these fellas will nail it for ya though

That backfire thing has only happened once. Never been able to repeat it.
The diagnostic box that I have seems to be pretty good but everything seems to be within spec. No fault codes. I just noticed this evening that the check engine flashes 10 times when I turn on the key. It is something new. I haven't had the battery disconnected for quite some time.

 

[RamDiver]

That backfire thing has only happened once. Never been able to repeat it.
The diagnostic box that I have seems to be pretty good but everything seems to be within spec. No fault codes. I just noticed this evening that the check engine flashes 10 times when I turn on the key. It is something new. I haven't had the battery disconnected for quite some time.

I believe that the CEL flashing a specific # of times is a specific fault indicator.

I can't locate anything on Ram Forum, using my phone ATM but here's something from an unknown source to review.

Dodge Check Engine Light Flashes 10 Times - Why? How To Fix?

Get expert tips to diagnose and fix the issue of "Dodge check engine light flashes 10 times". Keep your vehicle running smoothly. Learn now!

vehiclequeries.com

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[Hagar1]

I believe that the CEL flashing a specific # of times is a specific fault indicator.

I can't locate anything on Ram Forum, using my phone ATM but here's something from an unknown source to review.

Dodge Check Engine Light Flashes 10 Times - Why? How To Fix?

Get expert tips to diagnose and fix the issue of "Dodge check engine light flashes 10 times". Keep your vehicle running smoothly. Learn now!

vehiclequeries.com

.

It will flash 10 times for a while after the battery has been disconnected but according to some info I've read, it will flash if there is a "pending" problem. So far though, no codes and no CEL.
What do you think of some of the info I posted yesterday about spark retard?
Thank you for your help.

 

[NCRaineman]

It's possible to have gotten a bad tank of gas, or that the place you normally fill up at has problems with their tanks and the fuel is getting contaminated. Has this been going on through several fuel fills? Do you always get gas at the same place?

 

[RamDiver]

It will flash 10 times for a while after the battery has been disconnected but according to some info I've read, it will flash if there is a "pending" problem. So far though, no codes and no CEL.
What do you think of some of the info I posted yesterday about spark retard?
Thank you for your help.

Many of the ideas posted have good merit, it does sound like an ignition/timing issue.

The only flaw I see is that if the fault has been created by a mechanical failure such as cam phasor/timing chain or bad fuel, you would not expect it to clear when the engine reaches operating temperature.

I have two thoughts for you to ponder.

First, we're completely trusting your code reader to be operational and if it were failing to report codes, this troubleshooting task is much more difficult than it needs to be.

I would locate an auto parts store that would agree to scan your truck for free, I'm sure they're out there. This just proves your scanner to be functional and that we're not being mislead and wasting our time with misinformation.

The fact that you get 10 flashes after reconnecting the battery leads us to believe, a code should be captured and reported.

Next, I would carefully examine all the coil packs. I don't know if this would be a typical failure mode where it only works after warm but theoretically it would make sense.

Someone with more experience with Ram coil packs might know.

In theory, it would be useful information to verify all the plugs coloration but not very practical, time wise.


Hopefully, another scanner will yield a code and that will point you in the right direction.

One more thought, bad common grounds are notorious on older Ram trucks. Maybe the expansion that happens with warming up the engine restores the ground.

You might check the grounds on or near the block for corrosion.

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[Hagar1]

Many of the ideas posted have good merit, it does sound like an ignition/timing issue.

The only flaw I see is that if the fault has been created by a mechanical failure such as cam phasor/timing chain or bad fuel, you would not expect it to clear when the engine reaches operating temperature.

I have two thoughts for you to ponder.

First, we're completely trusting your code reader to be operational and if it were failing to report codes, this troubleshooting task is much more difficult than it needs to be.

I would locate an auto parts store that would agree to scan your truck for free, I'm sure they're out there. This just proves your scanner to be functional and that we're not being mislead and wasting our time with misinformation.

The fact that you get 10 flashes after reconnecting the battery leads us to believe, a code should be captured and reported.

Next, I would carefully examine all the coil packs. I don't know if this would be a typical failure mode where it only works after warm but theoretically it would make sense.

Someone with more experience with Ram coil packs might know.

In theory, it would be useful information to verify all the plugs coloration but not very practical, time wise.


Hopefully, another scanner will yield a code and that will point you in the right direction.

One more thought, bad common grounds are notorious on older Ram trucks. Maybe the expansion that happens with warming up the engine restores the ground.

You might check the grounds on or near the block for corrosion.

.

Thank you for the reply and the ideas. I have used that scanner on other vehicles and it worked as it should. I am puzzled that there is no CEL on continuously. The 10 flashes that I mentioned occur with key on, engine off. They start after the (bulb check) red indicator that sort of looks like a throttle body on the rt side of instrument cluster goes out.
As I mentioned earlier, I changed the plugs recently, within the past 1000 KM.
I had considered grounding because of past experience with other vehicles, so I ran a separate ground from engine to frame.
I'm going to check today with the auto parts stores here to see if they have a scanner.
I have a complete set of coil packs from an engine that I'm going to build but I don't know much about their history.
The cold driveability goes away but the fuel economy is still down. It dropped from 22 mpg on the highway down to 14. Once it warms up, there is no shortage of power.

 

[Hagar1]

It's possible to have gotten a bad tank of gas, or that the place you normally fill up at has problems with their tanks and the fuel is getting contaminated. Has this been going on through several fuel fills? Do you always get gas at the same place?

I typically buy fuel in one of two places and my other vehicle is OK. This problem has been going on for at least a couple of months. I considered fuel so I went to one gas station and bought 4 liters just to test. It tested at 3% alcohol, well within reasonable limits. I didn't check Reid Vapour Pressure though because I didn't think it was necessary.

 

[Hagar1]

An interesting item ..... I went into the OBD 2 functions to see if anything was logged there. It shows that it passed all the monitors, there were no "freeze frames" but .... cyl #7 and cyl #8 had 4 misfires during the last trip. Also cyl #6 showed 1 misfire. Not enough to trigger the CEL but ????
I think I am going to start by retorquing the intake and then change out a couple of coils.
The down side is that the coils on cyl #7 and #8 are the two nastiest ones to access. I have found it is a lot easier if I pull the fender liners.