'90 Plymouth minivan, 3.3l low oil pressure


  #1  
Old 10-08-07, 10:29 AM
CMil's Avatar
Member
Thread Starter
Join Date: Apr 2002
Location: United States of America
Posts: 393
Upvotes: 0
Received 0 Upvotes on 0 Posts
'90 Plymouth minivan, 3.3l low oil pressure

Just did another oil and filter change on my wife's minivan (500 miles ago), using a popular-brand-name filter and 10w40 oil. Pressure shows good on cold start-up (more than halfway over on gauge), but when engine warms up, the pressure drops enough at idle to turn on the "Check Gauges" light. It's still pretty warm here; should I stick with single-weight oil a little longer? Am I looking at replacing an oil pump, or internal bearings and rotating parts? Could a defective pressure sending unit be to blame? By the way, how many pressure senders are there on this engine? I drove a '91 Hyundai that had three separate senders; one for the light, one for the gauge, and one for the PCM. Maybe this is the norm, but it seemed a little much to me.
I'd like to keep this engine running as long as possible without requiring major repairs, and maybe even bump the performance a little bit. I'm looking into less restrictive air intake and possible ignition modifications. Anyone with performance experience with this engine or other suggestions? Please feel free to share! Thanks in advance - Chris
 
  #2  
Old 10-09-07, 04:04 AM
New guy's Avatar
Member
Join Date: Feb 2005
Posts: 425
Upvotes: 0
Received 0 Upvotes on 0 Posts
Sound like the "oil pressure sending unit" is bad, typical problem of 3.3L, it's located infront of the oil filter.

On the other note, I like the 5w30 for all year round as recommended per Chrysler.
 
  #3  
Old 10-09-07, 05:01 AM
billys68ss's Avatar
Member
Join Date: May 2003
Location: USA
Posts: 1,441
Upvotes: 0
Received 0 Upvotes on 0 Posts
You say a popular brand name filter like you are scared to tell us what filter you are using... LOL. A good filter is key to proper maintenance.
The oil sending unit wont likely cause the oil pressure to drop once warm, that is more likely an internal engine wear issue. Before I condemned the sender, I would put a manual gage on it and repeat the warm up procedure and see what happens. These engines dont usually have oil pressure issues unless they have been poorly maintained.
10W30 is the recommended weight oil for that engine, but if you are having oil pressure issues the 10W40 will be a little better.
Let us know what the oil pressure test shows.
Hope this is helpful to ya,
Billy

P.S. If you are having an oil pressure issue, then performance modifications are the last thing you need to be thinking of, plus it is a MINIVAN!!!
 
  #4  
Old 10-09-07, 05:24 AM
CMil's Avatar
Member
Thread Starter
Join Date: Apr 2002
Location: United States of America
Posts: 393
Upvotes: 0
Received 0 Upvotes on 0 Posts
Thanks, new guy and billy68SS. I didn't want to give the appearance of whoring for any manufacturer; the oil filter is the orange can with the black grip band at the bottom and the four-letter brand name! (Bet you can guess it now!)As to the poor maintenance, that's a possibility - we've had the van for the last 4 years/35K miles, and it's got well over 150K on the clock. It's seen pretty regular fluid and filter changes since we've had it, but who knows about before? It was my brother-in-law's before it was ours, and as part of the younger set, his biggest concern at the time was "thumpin' tunes".
Okay, okay, I know, who hot rods a minivan? I understand the argument, but I'm trying to coax my wife into seeing things my way. We have crazy traffic here in Branson, MO, and a little better acceleration, braking and handling would not go to waste. And if it's in a sleeper, so much the better! Your right, though, improving the performance of a tired, worn-out engine doesn't make a lot of sense. I will look at the pressure with a manual remote gauge and see what I'm dealing with first. Thanks again - Chris
 
  #5  
Old 10-09-07, 07:42 AM
billys68ss's Avatar
Member
Join Date: May 2003
Location: USA
Posts: 1,441
Upvotes: 0
Received 0 Upvotes on 0 Posts
Hey, im not knocking ya, Im all for the sleeper. I just think other things should take priority at this point. I have a 90 Caravan that I thought about doing the same thing to... good thing I didnt spend that money, cause it broke a rocker shaft and while I was replacing the heads, I broke a head bolt off in the engine block... Hence it has been sitting ever since. Oh Well.... My kids even threatened sending it in to Pimp My Ride and getting it Pimped out for me... THats Hilarious!!!
Good Luck,
Billy
 
  #6  
Old 10-09-07, 04:43 PM
CMil's Avatar
Member
Thread Starter
Join Date: Apr 2002
Location: United States of America
Posts: 393
Upvotes: 0
Received 0 Upvotes on 0 Posts
Let me guess; the broken head bolt is one of the lower ones on the rear head, right? Those rear spark plugs are fun to get to, also, aren't they? Pimp My Ride, huh? Ours is purple, so it's affectionately known as the Barney Bus. Ain't kids great? I'll post REAL oil pressure as soon as I get a chance to test it. 'Til then,... - Chris
 
 

Thread Tools
Search this Thread
 
Ask a Question
Question Title:
Description: