Yeah I know, not another ops thread! :eek:

I noticed this week my truck has been a bit of a dog. So this mornin' I reach under and feel nutin' from the lift pump. Check t-valve...nutin'!
I put power to fuse and LP operational again.

Long story short I go get a new OPS, put it in and "YAY" LP runs again. Shut the truck off and LP still goin'...uh-oh. Unplug new OPS LP stops. Do some checks and a see that orange wire to OPS is hot all the time. I'm pretty sure it's supposed to be, no? Orange wire to fuel pump relay is always hot accordin' to schematic, same wire???

I thought this mornin' they gave me the wrong OPS accordin' to the part number but was told it was a change up. I still think I have the wrong one so I'm goin' to get the proper AC Delco I think it is when I finish this post just to ease my own mind.

Will this cure it??? Would havin' the wrong OPS cause my LP to run all the time??? Someone before me bypass the OPS??? If they did, why did it work with my old OPS but not a new one???

I'm goin' to parts store now!

P.S Here is a pic of the socket I made to get the OPS out.

It was the wrong OPS!!!

The right one is AC Delco part number D1808A which is already in the part point sticky.

I take it that everything works alright now?

I replaced my OPS before I got in the accident and I used a crowsfoot. Works wonders in that tight space.

wrong OPS probably would not let lift pump come on vs keeping it on all the time

I put the right OPS in and it's been workin' fine. Also my oil pressure is a little bit higher now.

Depends on how long it runs after shutdown - oil pressure doesn't drop immediately in a functional system - LP should run after shutdown until oil pressure falls below set-point of OPS - up to 15secs is normal with new OPS, good bearings

Depends on how long it runs after shutdown - oil pressure doesn't drop immediately in a functional system - LP should run after shutdown until oil pressure falls below set-point of OPS - up to 15secs is normal with new OPS, good bearings

That's what I see with mine. Depends on how hot the oil/engine is. If I start it and run for only a minute or so and shut it down, the LP will run for up to 10 sec after the engine is shut down. After a long drive, the LP may only run for a second after key out. I was not aware that there is a "wrong" OPS. Good thing to know. Mine is still the original.

Well at first, that's what I thought it was, oil pressure bleedin' down then the pump would stop. It didn't stop! It ran for at least 5 minutes before I pulled the fuse to stop it. All good now and my oil pressure is showin' 3 ticks higher than before. It actually goes over half way now, yippeeee!!!

Good fix, then - post the 'bad' p/n if you have it - the 'good' one should be posted already in parts point

OK, here we go.
The "wrong" ops I was given was part number PS245 (standard parts, carquest). Well, I thought it was wrong. I cross referenced it at the ac delco website and it crosses to ac delco D1808A (gm #12555492) which is definetly the right one. So I guess the PS245 I got was bad to begin with since it's supposed to be the same as D1808A.

This is where I got all buggered up yesterday. When they gave me that PS245 it was supposed to be a change up from PS262 which I've seen in the part point sticky. It crosses to gm#12553175 and not to gm#12555492. Hmmmm different gm #. So it's supposed to be the same but it crosses to 2 different numbers. The usage for the PS262 says all gas engines, no diesel. Is this a big deal? I dunno!
So I figure, gotta be a wrong number and go get the D1808A which is also the PS245 but not the PS262! Whoa brain freeze:eek:

Anyway, if you need a new OPS, get D1808A, it is the right one.

GM#12555492 or Ac Delco#D1808A

IIRC somewhere here said to use the ACDelco ONLY instead of other brand for OPS because it causes some timing issue as you mentioned.