I need some help figuring this out. Here's the rundown:
On cold starts, ie first thing in the morning or after jeep sitting for 12 hours or so, my gauge shows a considerable lag in building oil pressure over what it shows upon startup when the jeep is warm. (running rotella 10w-30)
I've taken to mechanic, who put mechanical gauge on and drove 30 miles. He said it's reading pressure within spec at all rpms, and that if it's slow building pressure at cold start, it could be the oil pump weakening or a lot of sludge buildup.
Jeep has about 33,000 on it, but i just bought it a few months ago with 28,000--previous owner took really good care of it, but perhaps a sludge buildup then? I don't know.
Once the pressure is up, it's up--according to both the dash gauge and mechanical unit.
Before taking it in, I changed filters, changed oil, and pulled the sending unit and cleaned it out--none of these made any difference.
I've considered maybe a dirty screen on the pump pickup--but not really sure why pressure wouldn't be affected while driving if this is the case. The sending unit seems to be functioning normall otherwise, as it reads pressure while driving similar to the mechanical gauge.
I've talked to others online on jeep forum, many report this same lag in pressure buildup...I just have the feeling that it didn't always have such a lag--i tend to notice things like that, but it's possible i overlooked it before.
Jeep runs fantastic, no noise at startup or otherwise, gets fantastic mileage, no complaints anywhere other than this gauge!
Any ideas?
On cold starts, ie first thing in the morning or after jeep sitting for 12 hours or so, my gauge shows a considerable lag in building oil pressure over what it shows upon startup when the jeep is warm. (running rotella 10w-30)
I've taken to mechanic, who put mechanical gauge on and drove 30 miles. He said it's reading pressure within spec at all rpms, and that if it's slow building pressure at cold start, it could be the oil pump weakening or a lot of sludge buildup.
Jeep has about 33,000 on it, but i just bought it a few months ago with 28,000--previous owner took really good care of it, but perhaps a sludge buildup then? I don't know.
Once the pressure is up, it's up--according to both the dash gauge and mechanical unit.
Before taking it in, I changed filters, changed oil, and pulled the sending unit and cleaned it out--none of these made any difference.
I've considered maybe a dirty screen on the pump pickup--but not really sure why pressure wouldn't be affected while driving if this is the case. The sending unit seems to be functioning normall otherwise, as it reads pressure while driving similar to the mechanical gauge.
I've talked to others online on jeep forum, many report this same lag in pressure buildup...I just have the feeling that it didn't always have such a lag--i tend to notice things like that, but it's possible i overlooked it before.
Jeep runs fantastic, no noise at startup or otherwise, gets fantastic mileage, no complaints anywhere other than this gauge!
Any ideas?
