3 minor issues I'm hoping you can help with.

[partcheck]

Hey guys and gals. There's 3 minor issues I'm having on my 05 Tahoe Z71 that I hope you can help with.

1) Oil gauge shows max pressure. I changed the oil pressure sensor and the gauge functioned normally but then after a month, the pressure hit max again and stays there. Figured maybe a bad sensor so I replaced it again and the same thing happened after a month. I've been driving it for 3 months now with the gauge showing max pressure and there is no problem. What could be causing this? Both times I replaced with ACDelco sensor.

2) Whenever I turn on the heat, I eventually get a bad smell like oil burning or maybe coolant. If I turn the heat to upper vents and push the cabin circulation button, the smell goes away. This only happens with the front vents. Whenever the truck is stopped at a light, the smell gets worse.

3) When looking for the cause of that smell yesterday, I saw this. Looks like a leak? Any ideas?

 

[afpj]

2 & 3 are possibly related. That location is very suspicious for heater core T fitting(s) leaking. Look at those carefully. You didn't mention your mileage but you probably have over 100,000, if they've never been changed out, it's time.

For issue number one, could be your stepper motor but may need to check the harness to the oil pressure sender. Others much smarter than I can chime in on this. You might do a search as well, I've seen other threads mention a pegged oil pressure so probably could use that as a key word.

 

[partcheck]

2 & 3 are possibly related. That location is very suspicious for heater core T fitting(s) leaking. Look at those carefully. You didn't mention your mileage but you probably have over 100,000, if they've never been changed out, it's time.

For issue number one, could be your stepper motor but may need to check the harness to the oil pressure sender. Others much smarter than I can chime in on this. You might do a search as well, I've seen other threads mention a pegged oil pressure so probably could use that as a key word.

Thanks for your advice.

Forgot to mention that I replaced the cluster and this happened before/after new cluster so I'm pretty sure the stepper motor is okay.

I'll have to try removing the sensor again and checking that little filter.

 

[MassHoe04]

On the oil pressure... Do you have a scan tool that will show live data for oil pressure? You could see if the pressure sensor is reading correct and confirm the cluster gauge is showing the data correctly or not.

On the smell...
Have you determined whether the coil pack is wet with oil or coolant? Wipe it clean and see what, if anything continues to drip on it. It looks like coolant, but the road grime makes it hard to tell from the photo.

 

[partcheck]

No on the scan tool. I'll have to see if anyone I know has one I can borrow.

I haven't done much with that leak since finding it last night. I'm going to wipe it down during lunch today and see if I can pinpoint the leak after driving it a bit.

 

[Fless]

Wrap some paper towels around the heater tees and use zip ties to hold them in place. After a drive or two, check the paper towels for leakage.

 

[partcheck]

It's definitely one of those tees. Checking it out more closely I can see leakage all around that tee.





Any idea which is the correct replacement part?

2005 CHEVROLET TAHOE 5.3L V8 Heater Hose Connector | RockAuto

RockAuto ships auto parts and body parts from over 300 manufacturers to customers' doors worldwide, all at warehouse prices. Easy to use parts catalog.

www.rockauto.com

I think it's this one: DORMAN 800414 Heater Hose Connector - Auxiliary Heater; Inlet Hose Tee; Auxiliary Air Conditioning and Heater; 113 mm Length

Also, while in there I think I found a coolant leak. I replaced the radiator like 2 years ago. I put coolant in the other day and the tank is almost half empty already. I just can't figure out what hose this is. Is it the trans cooler line, right? I think I'm just going to replace both the upper and lower trans cooler lines.

 

[MassHoe04]

More likely your coolant loss is that fitting. It is constantly circulating whether heat is on or not. Aside from the coil pack from being wet, the fitting was likely spitting out while you were on the road.

The line you see there with the arrow would be carrying transmission fluid to the front, not coolant. If transmission cooler lines or the core for that was involved at all in your coolant loss, you might see coolant in the transmission fluid.
If transmission fluid is clear and not milky or weird looking, I would focus on the heater T's and replenishing the coolant for now and see what happens.

Replace the heater T's, top off you coolant and re-check the coolant level over the following weeks after driving long enough to get things up to temp and circulating a while.
Sometimes extra coolant is needed after air trapped in the lines or in the rear heater core gets burped out. The level drops a bit when the air moves out of the system.

AC Delco T's are preferred for longevity and fixing one time. But Dorman works in a pinch. I had one just snap at the hose and my coolant was being pumped out full-bore by the water pump until I could pull over. Dorman was available at NAPA and I needed right away. No leaks. Do I expect the Dorman to last 18 year like the factory part? No. But will probably last long enough for me and the time I end up having this Tahoe anyway.

 

[Logan5]

Those heater core Tee 's can sometimes be a ***** to take off, stuck back up in there like that. I tried like hell to get one off without breaking that little white release tab.

Then when I opened the new T it had a new white release tab.

 

[Donal]

Thanks for your advice.

Forgot to mention that I replaced the cluster and this happened before/after new cluster so I'm pretty sure the stepper motor is okay.

I'll have to try removing the sensor again and checking that little filter.

So you have the filter in the OPS opening and it a 2005? Did the filter come with the new switch? did the vehicle already have a filter?