The flows are correct. I put everything back how I removed.
I’m going to remove the rubber hoses attached to pipes into the heater core and manually fill one hose until fluid comes from the other one. I’m suspecting that the air lock is associated with the core.
What’s also throwing me is that the temperature sensor has been replaced recently and, as per a previous write up, is calibrate differently from the original one. My NANOCOM is telling me the temperature is exceeding 100C yet my instrument gauge is showing 1/4…. Not even half!!!!
I’ll report back tomorrow….
Having replaced the heater core, I put everything back together again, like Humpty Dumpty, and now the thing “appears” to have an air lock.
Symptoms are the NANOCOm is giving me a warning when its plugged in the the temp is going above 100C. I shut vehicle down and drained radiator and entire system from nut at bottom of rad. Refilled system again following steps in RAVE. Started up…. Same issue NANOCOM not happy with 100C.
After numerous various methods of bleeding system and usually getting the steady stream from top of radiator nipple I was still getting NANOCOM 100C warning.
I then replaced Thermostat and water pump but the problem is still there.
Bottom of thermostat is ambient temp, top is hot. Bottom of radiator is ambient and hose to top is hot. Running the heater gives heat so long as there is high RPM.
Is there a way to bleed this bleed in vehicle that’s tried and true? I’m at my wits end with it.
Changed heater core and O rings last week. Also changed the temp sensor on top of engine as it was part of my fault finding as I chased the cause of rough idle beginning 10 seconds after warm engine start that lasted another 15 seconds before idling normally.
Heater core replacement was painlesss enough and agree re wiggling pipes as you tighten the screw. There ended up being another 2 x 360 degree turns of the Phillips screw after wiggling the pipes, this after me originally thinking that they were tight enough. Been a week and 200 miles, no leaks.
I do, however, have another issue which I can’t tell is related to my work or a common issue.
I burped the system as best I could after replacing the core. I ended up putting approx the same amount of anti freeze in as I took out.
Remembering that I have a brand new temp sensor installed, I now find that when I drive that the temp indicator in dash is sitting at 1/4 reading and not the 12 o’clock position that it was at prior to the new sensor changing. The gauge doesn’t move up or down during a drive but stays in same position as if 1/4 reading was the norm. Engine idles fine and no roughness.
Any ideas as to why this is happening?
My first thought was air in system but I’d imagine that this would cause a high temp rather than a low one. My next thought is that the temp sensor is calibrated differently.
Beyond that I haven’t a clue…..
Heater core leaking
I’ve followed these steps, up to where I disconnect the pipes into the core, which has worked quite well….
http://www.brazeauracing.com/rangerover/heater/index.html
Now just waiting for a recommendation for a heater core replacement that will not have me redoing this again.
Anyone got a suggestion?
I have the NANOCOM and I will check engine temps tomorrow and report.
Thanks
Found this that may lead to Gilbertds’ thoughts….
Engine Coolant Temperature (ECT) sensor - (from99MY)
The ECT sensor is located at the top front of the engine, adjacent to the coolant outlet pipe. The sensor screws into a thread in the inlet manifold and incorporates a sealing ring between the faces of the sensor and manifold.The ECT sensor multiplug has four wires; two are thesignal and ground connections used by the ECM, the other two are used by the body control module(BeCM) for control of the temperature warning lamp operation on the instrument pack.The sensor contains two thermistors with negative temperature co-efficients; as temperature increases,the thermistor’s resistance decreases. The ECM receives a corresponding analogue input voltagebetween 0 and 5V.NOTE: The temperature / resistance characteristics of the two thermistorsdiffer, and so it is important to maintainthe correct pin-outs.The ECM uses the information received from the ECTsensor to make adjustments to the engine operatingconditions. The ECM ensures a richer air:fuel mixtureis available at lower block temperatures for good quality starts and smooth running. The mixture is then made leaner as the engine temperature rises to maintain low emissions and good performance.For NAS vehicles with secondary air injection, thesignal from the ECT sensor is monitored at engine start, to determine whether the conditions are coldenough to warrant secondary air injection to beemployed. The ECT sensor is then monitored to switch off the secondary air injection when therequired engine coolant temperature has been attained.
If the sensor fails, the ECM uses a substitute software routine that changes default value during warm up,based on the signal from the inlet air temperature sensor. When the software model reaches a coolant temperature of 60°C (140°F) the ECM implements a fixed default value of 85°C (185°F). The ECM coolant model also forms part of the diagnostics that is performed for detecting a temperature sensor fault, as well as open and short circuit tests.
Temperature Voltage
-50°C 5V
-20°C 4.8V
10°C 4.2V
40°C 2.8V
70°C 1.4V
100°C 0.6V
130°C 0.2V
NOTE: All voltages listed are approximate.
A coolant temperature circuit failure may result in the following symptoms:
• Poor cold and warm/hot starting and driveability.
• Instrument pack temperature warning lamp willilluminate.
• MIL will be illuminated.
• Temperature gauge reads excessively hot orcold.
• Cooling fan will not run
• SAI pump will operate at engine start up even when engine is hot (NAS with secondary airinjection system only).
I will try change the temp sensor.
Just check all power to the various SAI items. 12v is being powered to all parts. All the electrical equipment associated with the SAI are new items and still this stutter 15 seconds after a warm engine start.
With all the knowledge here on the forum there surely has to be an answer to this. Im using top grade fuel, did a Seafoam run twice. Coils, leads and plugs are all 6 months old.
FWIW, I did the voltage test between pins. When sun arises in AM I will check all the above from the earth point of battery and report back. In my defense, I did state in post that electricity os not my bag….
Failing all else, would there be a known work around this bloody “save the world” SAI system that will stop my vehicle from stuttering every time i start it when warm?
I went and did a voltage check on the power to:
Both have same 7 volts. Electrics are not my bag….
Would I be wrong in assuming voltage loss due to a bad ground?
Do both these systems share the same grounding point?
Would anyone have a wiring diagram of the electrical system for the SAI system?
I suppose I could but then I’d have nothing to do …….
FWIW, I put a multimeter at the plug for the solenoid and it reads 7.3V! Whats that all about?
Wits end….
MAF not the issue
SAI pump not the issue
New SAI Solenoid not the issue
When she was doing this I removed the hose from the SAI Solenoid leaving to the manifold then covered the pipe with my thumb, the engine idled correctly. When I released my thumb she went lumpy again. I then attached the hose and she had the same lumpiness.
There is vacuum…..
Where does the hose from the SAI solenoid that runs towards the firewall go to? IF this hose was disconnected along the route from Solenoid to wherever it goes would it cause this lumpiness? I cant for the life of me see where it leads to and the RR Maine-tenancy manual doesn’t help…
Cylinders 4 and 8 use different coil packs.
Swapped the SAI pump……. No change…. Issue still present.
SAI solenoid next up…..
I’ll also swap the SAI pump out with my “donor” at the same time….
Thanks Gilbert……
I’ve ordered a Secondary Air Injection Solenoid and will report back…
Cheers
She finally threw codes…
P0413 Secondary Air Injection
P0300 Multiple Misfires
P0308 Cylinder 8 Misfire Detected
P0304 Cylinder 4 Misfire Detected
Thoughts?
Gilbertd; I probably didn’t describe the issue correctly.
When I start the vehicle and it’s stone cold it has no issues, no rough idle …. All is normal. The roughness only occurs after I turn engine off, leave it off for anywhere more than 3 minutes, then restart it. Then she will idle normally for a few seconds, then idle rough for 15-25 seconds then smooth out again. After this she will operate fine with no roughness at any stage.
If I rev the vehicle a bit during this rough idle she will run smooth…. It’s the initial roughness after a warm start that’s the issue….
That being said, I will swap the IACV valves with my now fast becoming “donor” and see what’s what then report back.
Thanks
Title sounds like an adult movie but…..
2001 4.6.145,650 miles.
Brief recent maintenance history:
Changed the plugs, leads, oil, filter, cabin filters, air filter about 500 miles ago.
About 200 miles ago after starting when warm she starts fine, idles fine for about 5-10 seconds then idles rough (about 600-850 RPM) for about 15-25 seconds then smooths out and no issues at idle or driving. There are no engine warnings and the NANOCOM is not showing any faults. I swapped a brand new MAF out with my other restored P38 to no avail. I’m running the highest octane fuel and did a Seafoam additive at last service (145,000 miles).
She starts without this issue when stone cold….
Thoughts?
Thanks for all the input…. I’ve checked everything as mentioned prior to making the post….
I’m going to have to put it down to global warming and continue to top ‘‘em up…..