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oil pressure

2K views 15 replies 5 participants last post by  maniac mark 
#1 ·
hey guys question here, got a 93 safari TBI WITH 253 THOUSAND KM on the van the oil pressure creeps up to almost the high mark almost hitting the "H" while im driving or on the highway, while im idling it will come back down to middle or just below midline pressure some times it bounces around ive heard it could be my oil pressure switch, i hear these are known for that (even though my 2003 doesnt do it) is it time for a new switch? I would like to change it myself but my haynes manual doesnt give me exact location i know its screwed into the block somewhere. The van drives great no leaks ,new pcv valve and fresh 5w30 oil exactly 4.5 litres,any you guys ran into this before :think:
 
#2 ·
It would be best to put a master pressure guage on it to be sure something weird isn't going on.

However, it does sound like a sending unit problem. It is located either beside the oil filter, or behind the intake manifold on the engine block. It is about 3 1/2 inches long and sort of bell shaped.
 
#7 ·
I thought one of you guys would get around to asking that, Ive got a "wix" filter on it, bought from parts source, it is the proper one, i remember whenI brought home the van 2 weeks ago it had the same size and diameter on it from the last oil change which was a gm filter, I compaired them side by side.
 
#9 ·
oil was changed when i brought it home, before i got it it was done approx mid december, drove it approx 200km to my place and noticed the guage acting funny then, I think it had maybe five hundred km from the last oil change so i changed it , put in 5w30 did a bout 200 km, just changed it this weekend again and when i did it came out pretty dirty even after 200km. no i put i castrol high mileage 5w30, funny thing is i got almost 350km to half a tank city and highway combined!
 
#11 ·
Changed the oil pressure sendor unit today actually easy to acess only took me a bout 5min to chang it out, oil pressure works better now slightly more than half when driving then goes alittle down to half or just below when idling, at least not bopping around any more :bouncy: One last question if you guys could set me strait, ive read somewhere 10w30 in engine oil pressure guage will read lower as apposed to 5w30 oil pressure will read higher<I have 5w30 in her now, or next change should I put 10w30
To me it would make sence to put 10w30 since its 253000km mind you it burns no oil!! what do you guys think? :layrubber:
 
#12 ·
The 5 and 10 winter ratings only affect the viscosity of the oil when the oil is cold. Once your engine was up, it won't matter. That being said, I would go with the 10w-30 in the summer.

Out of curiousity, did you try cleaning out the old sending unit before you installed the new one?
 
#13 ·
Hi maniac mark

It really depends on where you live and how cold it gets. I run 10W-30 year round with mine and have since the van was new. 10W-30 is good to -18 Celsius. I have been in -25 C with mine with out any problems. That's what the dealership recommended to me (after the break in period) when I bought the van. Just my. :2: for what it's worth.:)
 
#15 ·
My point is that you may not have had to put on a new part. Those senders can get crud in them just like any other part of the oil system and that crud would give you funky readings. :2:
 
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