Xena
New Member
- Joined
- Jul 14, 2016
- Messages
- 32
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Dear All,
Close to frustration, I am posting my engine problem here in hopes that someone has encountered this challenge and was able to solve the mystery.
I'm from the Philippines and a proud owner of a 1997 Land Cruiser Prado, a KZJ95, my daily drive to work and everywhere.
It is equipped with a 1KZ-TE engine and an auto transmission.
I am also surfing the net and all other forum groups for Prado's and Landcruisers and other diesel sites. But so far I have not found a solution.
Last October 23, after coming home from a 25km uneventful drive, I got off and let the engine nicely idle but then in about a minute of idling it suddenly went wild giving off black smoke very similar to that of a "diesel runaway". I ran back to the car and saw engine RPM was beyond red mark on the tach. I turned off ignition. I then tried to re-start the engine and as soon as it started, began screaming again and RPM went redline and super black smoke filled the street.
Initial inspection showed that wires #1 and #2 on the Turbo Pressure Sensor was cut. I re-soldered the wires following its color code, but problem still same.
Note that EGR was already removed a long time ago and thus the venturi butterfly/valve has long since been removed. VSV's already removed long time ago.
No ECU DTC displayed, no check engine lights . Tried disconnecting the individual sensors one at a time and do a test restart and engine check will show the corresponding disconnected sensor in error. This tells me DTC is working
Troubleshooting done as of this time
1. Replaced turbo pressure sensor with original new Toyota part
2. Swapped ECU with known good spare
3. Swapped TPS with known good spare
4. Inspected all ECU sensor wires and connectors using Fluke digital meter. Referred to a Prado Electrical and ECU diagram.
5. Performed voltage and resistance tests based on Toyota service manuals. Tested Engine Speed Sensor, Correction resistors, TPS, Water temp sensor, Crank Position sensor, Fuel Temp Sensor, Spill Control Valve, Timing Control Valve. SPV and TCV have correct resistance and clicks when voltage is applied.
6. Disabled Positive Crankcase vent system as I saw oil on the intake area. Note PCV passes thru an oil catch tank which is regularly emptied during 5k oil change.
7. Removed and cleaned intake manifold of any oil residue.
8. Removed and cleaned injector nozzle and glow plugs.
9. Performed cylinder purging of any oil that may be there. Only a little came out and exhaust ports didn't show oil and only carbon deposits
10. Replaced Turbo when I still saw oil in intake even after disabling PCV. No more oil after replacement and cylinder purging but engine still wild at start up. Turbo is now new and no more oil seen.
11. Cylinder purging is done via cranking the engine over and over with high pressure air being pumped into the intake valves and whatever air or oil inside are being spewed out from the exhaust, injector nozzle and glow plug ports
12. Replaced engine oil and filter and no significant oil reduction noticed. No excessive emission smoke noticed prior to failure.
13. Drained Injection pump and replaced fuel filter and switched fuel source from main tank to recently filled sub-tank
14. Removed spill valve and cleaned fuel filter under it.
15. Removed Fuel Temp Sensor and cleaned fuel filter.
16. Tried to let the engine run a little longer than start/off, maybe 30 seconds of redline. I was hoping that any oil residues would burn off. . . no luck here too
In all these actions only the smoke color changed from black to gray when a new turbo was installed but then engine still goes redline upon startup.
I have now removed the Injection pump and will send it to a good calibration center.
Hoping for your kind assistance, I shall be forever grateful.
Jim
Close to frustration, I am posting my engine problem here in hopes that someone has encountered this challenge and was able to solve the mystery.
I'm from the Philippines and a proud owner of a 1997 Land Cruiser Prado, a KZJ95, my daily drive to work and everywhere.
It is equipped with a 1KZ-TE engine and an auto transmission.
I am also surfing the net and all other forum groups for Prado's and Landcruisers and other diesel sites. But so far I have not found a solution.
Last October 23, after coming home from a 25km uneventful drive, I got off and let the engine nicely idle but then in about a minute of idling it suddenly went wild giving off black smoke very similar to that of a "diesel runaway". I ran back to the car and saw engine RPM was beyond red mark on the tach. I turned off ignition. I then tried to re-start the engine and as soon as it started, began screaming again and RPM went redline and super black smoke filled the street.
Initial inspection showed that wires #1 and #2 on the Turbo Pressure Sensor was cut. I re-soldered the wires following its color code, but problem still same.
Note that EGR was already removed a long time ago and thus the venturi butterfly/valve has long since been removed. VSV's already removed long time ago.
No ECU DTC displayed, no check engine lights . Tried disconnecting the individual sensors one at a time and do a test restart and engine check will show the corresponding disconnected sensor in error. This tells me DTC is working
Troubleshooting done as of this time
1. Replaced turbo pressure sensor with original new Toyota part
2. Swapped ECU with known good spare
3. Swapped TPS with known good spare
4. Inspected all ECU sensor wires and connectors using Fluke digital meter. Referred to a Prado Electrical and ECU diagram.
5. Performed voltage and resistance tests based on Toyota service manuals. Tested Engine Speed Sensor, Correction resistors, TPS, Water temp sensor, Crank Position sensor, Fuel Temp Sensor, Spill Control Valve, Timing Control Valve. SPV and TCV have correct resistance and clicks when voltage is applied.
6. Disabled Positive Crankcase vent system as I saw oil on the intake area. Note PCV passes thru an oil catch tank which is regularly emptied during 5k oil change.
7. Removed and cleaned intake manifold of any oil residue.
8. Removed and cleaned injector nozzle and glow plugs.
9. Performed cylinder purging of any oil that may be there. Only a little came out and exhaust ports didn't show oil and only carbon deposits
10. Replaced Turbo when I still saw oil in intake even after disabling PCV. No more oil after replacement and cylinder purging but engine still wild at start up. Turbo is now new and no more oil seen.
11. Cylinder purging is done via cranking the engine over and over with high pressure air being pumped into the intake valves and whatever air or oil inside are being spewed out from the exhaust, injector nozzle and glow plug ports
12. Replaced engine oil and filter and no significant oil reduction noticed. No excessive emission smoke noticed prior to failure.
13. Drained Injection pump and replaced fuel filter and switched fuel source from main tank to recently filled sub-tank
14. Removed spill valve and cleaned fuel filter under it.
15. Removed Fuel Temp Sensor and cleaned fuel filter.
16. Tried to let the engine run a little longer than start/off, maybe 30 seconds of redline. I was hoping that any oil residues would burn off. . . no luck here too
In all these actions only the smoke color changed from black to gray when a new turbo was installed but then engine still goes redline upon startup.
I have now removed the Injection pump and will send it to a good calibration center.
Hoping for your kind assistance, I shall be forever grateful.
Jim