MY MYSTERY WRANGLER PROBLEM!!

[Gok Krish]

Body, Last week on Friday in @Wrangeld's Intermediate drive, I had car stalling issues towards the end. The computer cut the engine cut power off. I could restart, move 200 meters and then again cut off repeatedly. The vehicle was vibrating a bit. I had to be towed out the last 500 meters. A couple of months back, same happened in a drive with @Lorenzo Candelperghertowards the end. In both occasions, the incidence happened when mercury touched about 37 /38 deg C. But the car coolant temperature was well within the mid point not exceeding 110 deg C. For some part of the drive, I also had the car fan 'On' continuously with the Bullydog bypass setting and that did not allow the coolant temperature above 96 deg C. 

Loaded the car to a recovery truck and dropped it in the Trading enterprises, Um Ramool.  Even when parking after offloading, I could feel the vibrations and tendency to cut off.

Next day, the Service advisor calls me to tell that he has driven the car into the workshop, a test drive and found no issues in the car - everything is free of vibration and it was smooth. And he was asking me why I brought the car in the recovery truck. 

Wondering now what it is that has made this random cut off....and next day everything is normal

Went through forums in the net; in the JK's most issues happen from 1) crank shaft position sensor failure 2) fuel pump issues 3) loose contact in electricals - but is it just a coincidence that the issue happened when the temperature went about 37 deg C? I have asked Trading to do a test drive by manually setting 2nd gear at high RPM in mid day heat to see if they can simulate the same conditions where this failure has happened (I do not drive manual but the preceding this problem has been some load on the car during the drive)

Anyone, any suggestions to throw forward to Trading Enterprises folks to look into?

thanks 

Gok

  

[Niki]

@Gok Krishnow that is a frustrating report back from the garage.  what I can also share is a few of us also noticed a short period of white smoke coming out of the exhaust.  It wasn’t expelling smoke for long however certainly didn’t look a natural exhaust colour. 

I’ll allow the mechanics of the forum to comment more with this added reference.

good luck getting this sorted ASAP so you don’t have to miss many/any drives 

[Wrangeld]

Clearly, Trading Ents were not there - but all of us on the drive on Saturday saw the problem, and the white plumes of smoke out of the car when you restarted. With the greatest of respect to our esteemed engineerings colleagues, there was clearly something wrong with the car and you needed to bring it into the shop. 

What are the potential issues? 

1. Engine cuts off when it overheats to protect the engine/gearbox/transfer case? Unlikely as Jeeps are know to overheat.
2. An over expended compenent that puts the engine out of kilter? Unlikely ae the engine runs at high temperatures and under stress more often than not. 
3. Crank shaft position (not the sensor) - would have led to vibrations.
4. Fuel pump would not cause the vibrations we saw. Also unlikely to result in the smoke that was white - looked like cylinder head gasket had gone at the time. 
5. Did they put it on the computer and run diagnotics - the chip should be telling them what went wrong.  

 

 

 

 

[Gaurav]

Such cut off and white smoke after restart seems some sensor freaked out randomly or with heat (possibly).

Very surprise why dealership can't read the fault code.

@MUHAMMAD Kashif RAZZAQ you also had a intermittent white smoke few months back at IM drive on super bowl, do you recall what did mechanic said?

[Lawrence_Chehimi]

@Gok Krishi'm not an expert but did you check your coolant and engine oil? Is there any sign of water mixing with oil or did the coolant level decrease? As these are the main sings of a blown head gasket. Also Was it really a white smoke, not greyish or blueish smoke?

I have a feeling it is an engine misfiring issue, might be due to faulty ignition coil or a faulty injector...

[Ranjan Das]

Hi @Gok Krish, I had a similar problem twice with my Jeep some weeks ago; the engine cutoff power all of a sudden and unexplainably. Once while attempting a hill climb and the second while dashing through a sabka. The RPM just wouldn't go above 3.5k. it was surely hot and this happened towards the end of the drives. Though in my case there was no white smoke and i could drive the Jeep at lower rpm. By the time i was heading home after inflating, she was all fine again, accelerating properly even beyond 3.5k

Took it to the workshop, Diagnostics didn't throw up any error though they did find some problem with the oil pump. Since its a major repair, the workshop only serviced the pump assembly and asked me to see if the problem reoccurred before deciding next course of action - thankfully for me, it hasn't.

Hope yours was a freak incident as @Gaurav mentioned and nothing serious.

[Gok Krish]

4 hours ago, Niki said:

@Gok Krishnow that is a frustrating report back from the garage.  what I can also share is a few of us also noticed a short period of white smoke coming out of the exhaust.  It wasn’t expelling smoke for long however certainly didn’t look a natural exhaust colour. 

I’ll allow the mechanics of the forum to comment more with this added reference.

good luck getting this sorted ASAP so you don’t have to miss many/any drives 

Thanks @Niki...will highlight that white smoke issue

[Gok Krish]

4 hours ago, Wrangeld said:

Clearly, Trading Ents were not there - but all of us on the drive on Saturday saw the problem, and the white plumes of smoke out of the car when you restarted. With the greatest of respect to our esteemed engineerings colleagues, there was clearly something wrong with the car and you needed to bring it into the shop. 

What are the potential issues? 

1. Engine cuts off when it overheats to protect the engine/gearbox/transfer case? Unlikely as Jeeps are know to overheat.
2. An over expended compenent that puts the engine out of kilter? Unlikely ae the engine runs at high temperatures and under stress more often than not. 
3. Crank shaft position (not the sensor) - would have led to vibrations.
4. Fuel pump would not cause the vibrations we saw. Also unlikely to result in the smoke that was white - looked like cylinder head gasket had gone at the time. 
5. Did they put it on the computer and run diagnotics - the chip should be telling them what went wrong.  

 

 

 

 

Hi @Wrangeld Thanks, looking at some youtube videos to relate to the points, 4) cylinder head gasket seem likely cause. There is definitely some seepage of coolant into the cylinders in some combination of situations. Reg. codes, None captured. JK computer system has limited self assessment capability. I will hint it to the Trading Ent folks. Thanks for sharing the thoughts here....much appreciated...Good luck for the match shortly. 

1 hour ago, Ranjan Das said:

Hi @Gok Krish, I had a similar problem twice with my Jeep some weeks ago; the engine cutoff power all of a sudden and unexplainably. Once while attempting a hill climb and the second while dashing through a sabka. The RPM just wouldn't go above 3.5k. it was surely hot and this happened towards the end of the drives. Though in my case there was no white smoke and i could drive the Jeep at lower rpm. By the time i was heading home after inflating, she was all fine again, accelerating properly even beyond 3.5k

Took it to the workshop, Diagnostics didn't throw up any error though they did find some problem with the oil pump. Since its a major repair, the workshop only serviced the pump assembly and asked me to see if the problem reoccurred before deciding next course of action - thankfully for me, it hasn't.

Hope yours was a freak incident as @Gaurav mentioned and nothing serious.

Hi @Ranjan Das Ha ha, I am not alone... I just need these guys to get to the bottom of it and sort it out...paying a visit sometime tomorrow for a joint test drive...thanks for chipping in 

4 hours ago, Niki said:

@Gok Krishnow that is a frustrating report back from the garage.  what I can also share is a few of us also noticed a short period of white smoke coming out of the exhaust.  It wasn’t expelling smoke for long however certainly didn’t look a natural exhaust colour. 

I’ll allow the mechanics of the forum to comment more with this added reference.

good luck getting this sorted ASAP so you don’t have to miss many/any drives 

thanks for reminding me on the smoke part.... @Watteau also reported same....I will highlight that to the Experts in Trading ent...

[MUHAMMAD Kashif RAZZAQ]

Yes @Gaurav, I had this incident a couple of months back. Though it was Black Smoke rather than White. 

My mechanic diagnosed it instantly, turns out I had a faulty Mass Airflow Sensor, which messed up the Air:Fuel ratio causing my spark plugs to blow up, hence why the black smoke. 

Considering the symptoms mentioned by @Gok Krish, I highly doubt a faulty Airflow sensor would be the cause.

[Thomas Varghese]

18 minutes ago, MUHAMMAD Kashif RAZZAQ said:

Yes @Gaurav, I had this incident a couple of months back. Though it was Black Smoke rather than White. 

My mechanic diagnosed it instantly, turns out I had a faulty Mass Airflow Sensor, which messed up the Air:Fuel ratio causing my spark plugs to blow up, hence why the black smoke. 

Considering the symptoms mentioned by @Gok Krish, I highly doubt a faulty Airflow sensor would be the cause.

Or probably the air filter box was not sealed properly after last cleaning of the air filter and sand intrusion made the MAF go crazy which in turn panicked the ECM into cutting off the power.