2014 Tahoe Oil Pressure - potholes?

[ppvfan]

I've had my 2014 PPV (140,000 miles) for a week and have been carefully watching the oil pressure. Everything was good until this morning. I was trying to avoid some potholes on a gravel road and managed to hit a few. My check engine light, oil pressure light and warning came on immediately. I wasn't looking at the pressure just before that so I can't say if it was already dropping.

The oil level was fine and I drove it home by stopping every couple of minutes and shutting it off.

I let it idle for 15 minutes and the gauge is showing a steady 12 psi.

I'm doing an oil change today and am going to order a new sensor and filter screen.

Any other ideas why this happened after hitting a pothole? Thanks.

 

[wsteele]

Maybe the jostling of the pot hole disturbed some of the crap in the filter under the sensor and helped block it further? JSWAG.

FWIW - The '07 shop manual says 12 PSI hot idle is well within factory spec. Although my '07 with similar mileage to yours warm idle is around 29 psi, 12 would make me nervous.

 

[ppvfan]

I did the oil change and it came out pretty dirty despite being done in March, 3000km ago. A week ago I added Seafoam and wonder if that cleaned out some crap. I've never used it before so I'm not sure what the result looks like. In any case the pressures are back to normal now. I even hit a pothole with no ill effects.

 

[Bill 1960]

May have jarred a loose wiring connection.

 

[Miami-Dade]

I did the oil change and it came out pretty dirty despite being done in March, 3000km ago. A week ago I added Seafoam and wonder if that cleaned out some crap. I've never used it before so I'm not sure what the result looks like. In any case the pressures are back to normal now. I even hit a pothole with no ill effects.

I would do a couple of very short [3K or less miles] oil changes with Mobil 1 with the grade your vehicle calls for which is 5w30. But that is just me.

Out of curiosity did you get any service records?

 

[1BADI5]

Could be the o ring on the pick up tube or the VLOM.

What was "normal" oil pressure before. Seafoam will dilute the oil and could cause a drop in oil pressure.

With your mileage, I would be running 10w30.

 

[ppvfan]

I would do a couple of very short [3K or less miles] oil changes with Mobil 1 with the grade your vehicle calls for which is 5w30. But that is just me.

Out of curiosity did you get any service records?

That's what I was thinking too. I found some Mobil 1 on sale today so that was convenient.

I have the service records and it was serviced every 8,000 km or less. Lots of items replaced like the rad, differential, AC compressor.

 

[ppvfan]

Could be the o ring on the pick up tube or the VLOM.

What was "normal" oil pressure before. Seafoam will dilute the oil and could cause a drop in oil pressure.

With your mileage, I would be running 10w30.

The O-ring is on my list to replace. Hope it's nothing to do with the VLOM.

I didn't notice any difference in the oil pressure after I put in the Seafoam. Until today that is.

Thanks to everyone for the ideas.

 

[Geotrash]

The O-ring is on my list to replace. Hope it's nothing to do with the VLOM.

I didn't notice any difference in the oil pressure after I put in the Seafoam. Until today that is.

Thanks to everyone for the ideas.

Could be your smoking gun. Seafoam is a detergent and likely loosened up a lot of deposits which then got pumped through your oil pressure sender screen.

 

[1BADI5]

Well the VLOM can loose PSI because of the bolts. The bolts that secure it in the valley (below the intake manifold) can come loose; they're 13mm bolts. I know on my truck the 6 bolts closest to the front of the motor we either finger tight or less. Little things like this are easy to check, but to check the rearward bolts you'll have to remove the intake manifold; that's about a 45 minute job depending on your available tools and skill sets.

Also there is the oil pressure sensor on the back of the motor behind the intake manifold. It can be a pain in the dick to do, I did mine when I had the intake manifold off. There is the sensor right there on top in plain view, but under that sensor there is a little filter/screen under it. If that gets clogged up, that can cause a loss in measured oil pressure. Its a pretty straight forward job. When I was in there I replaced the sensor and screen.

If you have any questions or advice on the above mentioned items, feel free to ask..... there is a **** of well versed and experienced members with these issues. Good news for you these are very much DIY fixed which will and can save you a mountain of cash by not having to pay a shop to fix these little things.

Again, higher mileage. I'd run the larger oil filter and 6.5 - 7.0 qts of 10w30.