First time Jeep owner with a blown engine??

still in school

New member
I just picked up my first Jeep from a few states away. Made the 13hr trek back home without any issues. 07 Jeep Unlimited Rubicon (auto) with 120k on the clock. Good condition, well maintained vehicle. Mods are as follows: 4.5" BDS lift kit, 20" Poison Spyder wheels on 35's, 5.13 gears and Bully Dog GT. The only issue was a "wobble" shake at 40mph, regardless if you're accelerating or decelerating.

Driving home, the transmission never showed any signs of having issues. Earlier today, after napping from my long trek, I decided to meet up with a buddy whom also has a JKU for a cold one. On my way, I needed to punch it to get over so I can get onto the next freeway. Executed and got over just fine but I noticed the engine was still in high revs, so I glanced down and notice that the RPM was up there in the range. Glanced over at the BD computer and it shows that I'm in 3rd gear still with transmission temp at 173F. I then proceed to let off the gas and reapply a little throttle, transmission now engages into 4th. Cool, I thought to myself. Except I wish that were the case. I noticed I was losing speed and any attempt to apply more throttle had little use except for shooting up the engine revs. As I then coast off the freeway, the engine cuts out.

At this point, I decided to attempt to fire her back up but nothing. It was dead silent. I then turned the key to the ON position and looked at my engine temp gauge and it was at MAXIMUM, glanced over at the Bully and the transmission temp was 1,100F!! I then sat it out and let it cool down for over an hour. When I attempted to start the car, it was really hesitant and sounded really weak. My buddy went across the road and just got a whole new battery. Installed that and the Jeep sounds as if it's almost about to start. It turns over once or maybe twice. Tried again but it's less action and now I get an "electronic" burn smell from the vicinity of the starter.

After getting it back to the house, I unplugged the Bully Dog tuner and turned the ignition and she actually woke up! Except now she makes noises. Check video below (tinypic link).

Any help would be appreciated. And if anyone is a Jeep mechanic in the Houston area, please PM me. Attached are a few pics for your viewing pleasure.

14xp2ds.jpg

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[video]http://tinypic.com/player.php?v=64ntvk&s=9#.V3FlJdIrKUk[/video]
 

trailraider

Active Member
welcome to WAL.

certainly sucks.
what was your tuner set to during the trip? I've seen programmers take out transmissions if set to hot for to long a period of time.
 
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still in school

New member
welcome to WAL.

certainly sucks.
what was your tuner set to during the trip? I've seen programmers take out transmissions if set to hot for to long a period of time.

thanks for the welcome! hopefully this experience doesn't steer me away from Jeeps. i must say, i did enjoy the few hours I had though!

Actually, come to think about it. I've been refueling with regular on my entire trek home and I actually never touched the tuner. Once this episode occured, I played around with it and the previous owner had it on "Performance" tune. Do you think that could've caused it? If so, does that mean the engine is done for?!

Well, if the engine is toast there is a 4.1 stroker kit for that engine.

I just looked it up, it's quite pricey! If it was more within reason, I would probably go for it.
 

FLKEYSJK

Member
Actually, come to think about it. I've been refueling with regular on my entire trek home and I actually never touched the tuner. Once this episode occured, I played around with it and the previous owner had it on "Performance" tune.
I would check the tuner website to see what gas grade is required because many tuners require premium gas to work with the tune. By putting regular in it you could have been having premature detonation which can blow an engine. (I'm no expert here but this is what seems to have happened.)
 

rogerk93

New member
That really sucks, I really don't know what options you have but I would call the previous owner and see if he had any issues because that would not have happened for that short time having it.
 

still in school

New member
I would check the tuner website to see what gas grade is required because many tuners require premium gas to work with the tune. By putting regular in it you could have been having premature detonation which can blow an engine. (I'm no expert here but this is what seems to have happened.)

Website says 91+ ouch..

That really sucks, I really don't know what options you have but I would call the previous owner and see if he had any issues because that would not have happened for that short time having it.

He's never had any issues. He's been honest with me since day 1. He stated everything that was wrong with it.

Interesting enough, I after a vast amount of time searching, I found out about how a cracked header can cause a "knock" so I went ahead and pulled that and guess what I found? Also, the previous owner stated that he used 6qts of oil while doing an oil change for me for my trek home and this is what is showing with a cold engine..

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In the mean time, I'm going to change the following:
-spark plugs
-oil & filter
-uninstall tune
-knock sensor
-put a bottle of octane booster in the tank
Anything else you would recommend?
 

lonewolf

New member
I then turned the key to the ON position and looked at my engine temp gauge and it was at MAXIMUM, glanced over at the Bully and the transmission temp was 1,100F!!

It won't show you the correct trans temp with key in ON position. The engine needs to be running. I also don't think your engine temp was at Max. Must be just the gauge/sensor/wiring.
 

jeeeep

Hooked
once you set the tune back to stock, reset the ecu:
1. Disconnect the battery by removing the positive battery cable
2. Ground the positive cable to the negative cable for 30 seconds to erase the electric charge in the capacitors
3. Reconnect the positive cable to the battery
4. Turn the key to on but do not start
5. Turn the headlights on
6. Turn the headlights off
7. Turn the key off
The ECU has now been reset to its factory settings. for the next 50 warm up periods the ECU will relearn the engine and driving habits for your driving conditions and the newly installed parts

be sure to program for proper axle gear ratio and tire size before driving it. it could be the tire size was not programmed correctly to begin with. to set tire height, measure from center hub to the ground and multiply by 2
 
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still in school

New member
It won't show you the correct trans temp with key in ON position. The engine needs to be running. I also don't think your engine temp was at Max. Must be just the gauge/sensor/wiring.

Engine temp was definitely maxed out. While stranded, I would continuously turn the key to the ON position and it would gradually decrease over time.

once you set the tune back to stock, reset the ecu:
1. Disconnect the battery by removing the positive battery cable
2. Ground the positive cable to the negative cable for 30 seconds to erase the electric charge in the capacitors
3. Reconnect the positive cable to the battery
4. Turn the key to on but do not start
5. Turn the headlights on
6. Turn the headlights off
7. Turn the key off
The ECU has now been reset to its factory settings. for the next 50 warm up periods the ECU will relearn the engine and driving habits for your driving conditions and the newly installed parts

be sure to program for proper axle gear ratio and tire size before driving it. it could be the tire size was not programmed correctly to begin with. to set tire height, measure from center hub to the ground and multiply by 2

Previous owner did have the proper axle gear ratio and tire size set in the tuner. I had quite a bit of time on my hands with the HOT motor. I will definitely reset the ECU once all my parts arrive.

The more I think about this, I'm leaning more towards a fuel issue due to the following reasons:
-loss of power on the freeway but electronics were still working
-loss of power immediately after high engine RPM
-no CEL codes
-the more I attempted to start the car, the closer the engine would get to actually turning over. Which it eventually did when it was towed home and after a few additional cranks.
-knocking noise, running too lean

The only thing countering this is that I actually hear a whining noise in the rear when I put the key to the ON position. I'm going to rent a fuel pressure test kit from AutoZone tomorrow.
 

still in school

New member
And...completely ignored. LOL! :cheesy:

I'm holding off on the header purchase since I've sourced a motor locally that has them already on there. I want to try to get to the bottom of this before tossing in the towel and buying another motor (without breaking the bank).

For an 07', 5.13 and 35's is perfect. Please do not speak of which you know nothing about.

Before purchasing the Jeep, I vaguely remember seeing a chart and 5.13 for 35's were within range.

Do these 3.8L engine's main fuel line have a test port? Or am I looking at having to remove the intake manifold?
 

swampdog

New member
For an 07', 5.13 and 35's is perfect. Please do not speak of which you know nothing about.

He's in Sport with a D30. 5.13 is a small pinion in that little housing. Some can make it work offroading, but I would bet that's the exception, not the rule.
 
I'm holding off on the header purchase since I've sourced a motor locally that has them already on there. I want to try to get to the bottom of this before tossing in the towel and buying another motor

So your going replace other stuff that isn't broken but ignore the huge crack in the exhaust manifold?


Sounds like you got it all figured out. Why did you come here and ask for opinions?
 
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