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Messages posted by: GreenDieselEngineering
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We have not tested other starters, but there are several on the market that would provide faster cranking speeds. It would be important to make sure the pinion is matched for the flywheel and the alignment is correct. We are not aware of any off-the-shelf starters for the KJ and some manufacturer design work might be necessary.

During our cold start tests the last few days, we have noticed significant variance in start times based on battery voltage. The red top in our 06 is starting to go...fast. With the coolant temps around 5 C the 2006 KJ started in 2.35 seconds and the battery voltage was at 10.7V. In the 2005 KJ the start only took 1.0 seconds and the battery voltage was at 11.2V. The lower system voltage affects the glow plug temperatures and the voltage supplied to the injectors. This reduces the engine's ability to have optimized combustion. Once the engines started and the alternators kicked in, the voltage on both vehicles stabilized at roughly the same point. We are replacing the battery today in our 06 KJ and will post results in a few days.
Good questions. The fuel economy drop in the winter can drop significantly in the winter. We see a general decrease around 10%, but this can vary based on conditions. The fuel tends to be the largest factor. You might see an additional 5% drop if the vehicle is strictly a commuter due to having a cold start in the morning and a cold start returning home. The cold oil requires a few minutes to warm up. The lighter viscousity 0-W40 oil helps reduce the FE drop.

We are noticing that with the tune the warm-up is quicker with decent heat in cabin in about a 1/2 mile of city driving. The advanced timing helps transfer more heat to the coolant, should be directionally correct for improving the FE.

Fuel temps can effect efficiency, but it is usually not a big factor. Temps in the range of 30C to 50C at the engine fuel inlet are optimium, colder temps may have slightly more ignition delay and this will tend to drop the fuel economy. With the tune, the higher injeciton pressures help to increase the fuel temps in the common rail and minimize the ignition delay. The pressurizing of fuel in the rail can add between 30-70 C to the inlet fuel temps. The return fuel temps are also slightly higher to help warm the fuel in the tank faster.

The fuel heater has minimal impact on increasing the system temps. The injection system heat load is at least 100 times greater and probably more. We will instrument one of our KJs to see the temperature difference across the fuel heater and the return line to the tank. After a few weeks of monitoring we should have some hard numbers for you.
We are still going strong with the new torque converter offered through Mopar. It is a marked improvement over the stock units.

We have been testing it with our stage II turbo kit and the power delivery is phenomenal with the transmission in lock-up. At this point we are recommending the converter to all CRD owners that want to rid themselves of "shudder". It makes us shudder just thinking about failing a stock converter pulling a trailer up a mountain! It is well worth the cost to upgrade.
It is a known issue that the ceramic glow plugs have longevity issues in the KJ CRD. The plugs used in these vehicles were 1st generation and are prone to failure from overheating and other internal design issues. There are several different ECU releases during the two model years and if your vehicle is not running a fairly new release then the glow plugs could be more as risk of failure. To date our tunes have focused on fuel economy, drive ability and performance. We are now starting to review the glow calibration and will be including the most up to date release in all our tunes regardless of the ECU firmware level.

We have successfully translated the glow logic from the latest firmware to the older version and tested it on a 2005 vehicle. The next step is to do the same with a 2006 vehicle and then perform daily validation with the cooler temps to verify the functionality. The goal is to have new tunes available by 21 October.

Additionally, we are planning to lengthen the time the glow lamp is illuminated on the dash. We are only planning to add about 0.5 seconds to the light. This will help remind customers to delay cranking the engine in cold conditions to give the glow plugs adequate time to warm-up.
There is another factor that makes the Jeep take a little longer to start when compared to the older VWs. The KJ is a common rail engine and the first 2-3 engine revolutions are used to fill the rail with fuel and pressurize it to the proper pressure. During this time, the injection is not yet even activated. The older VW had unit injectors that are capable to fire immediately.

The tune added the rpm flare right after the start to assist with a stable idle and to help build vacuum slightly quicker than the stock calibration.
Good question. We have noticed this on both of our vehicles as well. In warm conditions the start is very quick, then in the range of 40-50 F the crank times are about 3 seconds. As the temps get lower, the starts begin to improve again. We saw 1-2 seconds at 30 F a few days ago. The temperature range you are having issues with is when the glow plugs stop having pre glow or it is so short the glow light barely flickers. We have not modified the glow calibration yet, but the longer crank times in mid-ambient temps may justify seeing if we can have the glow plugs on for a second or so to get some heat in the chamber. With a cool engine block the start ability is not the best without any preheating of the glow plugs. Let us know how the start times change with varying temps as the winter rolls in...it should improve.

The other issue with the KJ CRD when comparing to other diesels on the market relates to the starter and cranking speeds. The gearing and torque of the starter is only producing cranking speeds of about 105-110 rpm in very cold conditions. Other products will have cranking speeds of 120-140 rpm in the same condition. This difference in speed is huge when we want to compress the air in the chamber. The faster the cranking speeds, the more heat build-up due to compression and less leakage past the rings.

If anyone else has noticed this or other variance in cranking times, please let us know.
We have shipped to Canada. The shipping time takes a day or two longer depending on your location and we have to fill out a couple customs forms, but generally it is not a big deal. We use USPS for all our shipping due to only having a PO box at this time. The cost for the product remains the same.
Torque Converter Replacement Pointers

1. Disconnect battery.
2. Make sure vehicle is secured on a lift or up at least 10 inches on jack stands.
3. A tranny jack is a must for supporting the trans after disconnecting from engine.
4. Remove mechanical fan with a large crescent wrench or equivalent. May need to hold the fan hub pulley in place while hitting the wrench with a hammer, it is a standard thread so left to loosen.
5. Remove wiring from starter and remove starter (3 bolts).
6. Remove torque converter access plug, located just above starter.
7. Remove front skid plate (4 bolts).
8. Pull transmission line connector off the attachment stud on the bottom side of oil pan. This provides enough play so trans cooler lines do not have to be disconnected.
9. Remove front propshaft (NOTE: use paint pen to mark both shafts when removing so they are re-installed in same orientation this will make sure the balance is maintained), may need to use a punch to pop out CV joint after bolts are loose as it tends to freeze in position. Having the trans in neutral may make disassembly easier.
10. Remove 4 bolts holding rear driveshaft to axle, let the drive shaft hang down.
11. Disconnect the two exhaust hanger isolators from the crossmember.
12. The front hub on the engine has a 20-21mm nut that is used to rotate the engine over clockwise to get the 4 torque converter bolts to line up in the access window just above the starter.
13. Line up each TC bolt in window and remove one at a time, then rotate engine 90 degrees and proceed with next bolt until all four are removed.
14. Remove all the bolts holding the transmission to the engine, minus the two that are on the topside of the trans.
15. Remove the six crossmember bolts, while having a jack supporting the transmission.
16. Lower the transmission as far as it will go, now you will have access to the two bolts at the top of the trans that are still holding it to the engine (keep slight pressure on the jack).
17. Use a swivel and long extension to reach the two bolts from underneath the vehicle, the approach should be from the driver’s side of the vehicle.
18. Jack up tranny a little bit and then pull the unit rearward until it disconnects from engine.
19. Disconnect the 10mm bolt that holds the transmission dipstick to the trans. Pull the dipstick upward until it pops out of tranny (may need to lower tranny for this).
20. Now the unit can be lowered and pushed further back so the torque converter can be removed.
21. Make sure have a drip pan underneath bell housing when removing converter as 1 to 3 quarts of fluid will drain out of converter.
22. Re-install in reverse order, make sure to align the dowel pins on the engine adapter plate to the bell housing and tighten one attachment bolt to pull the units back together.
23. Note when installing the four bolts that hold the torque converter to the flywheel. Get all 4 bolts installed one at a time, but just hand tighten and back out ¼ turn until all four are installed. Then torque each one and finally complete a torque check on each bolt after the sequence is complete. There is no sense to short cut this and risk a torque converter becoming loose.


The process takes about 6 hours for an experienced mechanic, budget 2-3 hours more for the weekend warrior.
At this time we have put about 1500 miles on one of the European converters and no issues to report. The trailer towing was uneventful, typically a good thing with us! No shudder present, however the driveline vibration can be a bit higher due to allowing higher torque in lock-up conditions. The energy amplitude transmitted through the powertrain mount system is higher, but in the end it is a Jeep. We prefer capability over refinement in ride quality from an NVH (noise, vibration, harshness) standpoint. The flogging will continue!
The coolant gauge TSB is a flash update to the cluster controller, this is a separate module and will not effect the GDE tune.
The transmissions in both vehicles are stock besides the torque converter. We have spoken with a few customers that have shift kits and the effects seem varied. We may try one to see what benefits are realized. Not sure how much effect a kit will have since the diesel is a slow revver compared with a gas engine. Does anyone have a shift kit with our tune that could weigh in?
Now I get it. There is nothing like that built into the KJ. The VW is an older product design and uses the vacuum butterfly on shutdown. The Jeep has the FCV (intake throttle) that accomplishes the same task, but it is fully electronic and faster. The FCV and EGR valve normally work together to control the flow of fresh air into the engine with a stock configuration. With the ECO tune the EGR is off, but the FCV will still shut on engine shutdown to reduce engine vibration to reduce mount excursion.
Last week we installed two of the recently released Mopar torque converters with part number 68037142AA. This unit has a higher capacity lock-up clutch in order to eliminate any potential shudder from the vehicle. We installed one unit into a 2005 and the other in a 2006 KJ CRD.

We have tested the converter without pulling a trailer using both the ECO tune and HOT tune. The converter is a marked improvement over stock and we were not able to initiate any shudder with the ECO tune or HOT tune. We tried simulating a trailer load by modulating the brakes to hold 1700rpm in 3rd gear lock-up and even with full fueling the converter would not shudder. This proceedure was repeated at 50 rpm increments up to 2300 rpm and everything functioned well.

The plan is to complete trailer tow testing by next week and provide more data on the forum when complete. So far we are very pleased with the converter!
What is the "anti-shudder valve"?

The EGR is not actuated in normal driving conditions. We will open it for about a half second on a very fast tip out of the throttle after a hard acceleration to help bleed pressure off the intake side and reduce forces on the turbo. This has given rise to customers worrying that if the EGR valve is plugged there may be other issues long term. We also have a complementary feature for the fast tip out situation. We open the turbo vanes, which reduces the tubine speed of the turbocharger and pumping losses through the turbo. This also reduces the stress on the rotating components inside the turbo. In any case, there is not reason to spend money to fix a failed EGR valve...unless it has failed open. If it fails open you will have clouds of black smoke during an acceleration from stop and a very noticeable lag.
The turbo timer is not part of the GDE tune and there is no provision for it in the base software that is part of the vehicle architecture. An after-market unit would be your best best if this is a requirement for you. We typically do the self timer and let the vehicle idle for at least 30-60 seconds prior to shutting it down after running the engine hard.
 
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