01 Sonoma low oil pressure at idle and service engine soon light

[two-wayman]

I have an 01 2.2L auto with 50,000 miles and just put a new alternator on about 220 miles ago. Today my service engine soon light came on and is staying on. I have checked all sensor connectons to make sure all plugs are hooked up correctly and I found no problems. Any suggestions?

A problem I have had for a while is low oil pressure at idle. Now I have a friend who has a 4.3 and his oil pressure stays about the same all the time it doesnt jump around like mine. At idle my oil pressure stays about 18lbs of pressure now when I hit about 1500 RPM it shoots up to about 40 and tops out around 60 when I am running 2300 RPM plus. I have tried many different brands of oil and currently I am running 10w30 Mobil1 synthetic oil. Any suggestions on my low oil pressure problems?

Thanks in advance for any help.

[rlith]

Originally Posted by two-wayman

I have an 01 2.2L auto with 50,000 miles and just put a new alternator on about 220 miles ago. Today my service engine soon light came on and is staying on. I have checked all sensor connectons to make sure all plugs are hooked up correctly and I found no problems. Any suggestions?

A problem I have had for a while is low oil pressure at idle. Now I have a friend who has a 4.3 and his oil pressure stays about the same all the time it doesnt jump around like mine. At idle my oil pressure stays about 18lbs of pressure now when I hit about 1500 RPM it shoots up to about 40 and tops out around 60 when I am running 2300 RPM plus. I have tried many different brands of oil and currently I am running 10w30 Mobil1 synthetic oil. Any suggestions on my low oil pressure problems?

Thanks in advance for any help.

1st, go to advance autoparts and get your code scanned, that way we can help you better...

2nd, your oil pressure is fine... They typically drop to 20-25 at warm up idle, then go to 40 while cruise and 60 or so when givving it gas.. You should eb running 5w30 (manufacturer spec)....

[two-wayman]

I thought the manufacturer reccommended 10w30? I may be wrong. I guess I can give 5w30 a try next oil change. Thanks for the info

[rlith]

5w30 for our engines...

[two-wayman]

Thanks for the reply. I will start running 10W 30 next oil change.

I had the smog pump replaced which is what the code was calling the secondary air injection system. It cost about 420 bucks to fix at a local chevy\GMC dealer.