Birty Dastards Jeep Club

Tech Forum => Workshop => Topic started by: brick on August 20, 2010, 09:13:39 PM

Title: Oil pressure gauge HELP
Post by: brick on August 20, 2010, 09:13:39 PM
Hello good people. I think I need some help here.

I have had my Jeep since February time and all has been well so far (well apart from dropping an idler pulley) But...since last week I have had a problem with the oil pressure gauge. From time to time, and for no clear reason, the oil pressure gauge just rapidly drops to zero and I get the check gauges warning light come on. Then... sometime just as lightening fast, sometimes after a few seconds (5'ish is the record) it springs back up again to normal. It never over reads or under reads and has always been steady as a rock at between 4 and 5. Sometimes it doesn't do it all day and other days it just does to scare the crap out of me I'm sure. The only other related event I had was about a month ago all the gauges, except the oil pressure gauge (typical) dropped to zero whilst driving and a thump of the clocks brought them back again and all has been well.

So... my question is:
1) Anyone heard of this before and a fix
2) Can anyone point out where the oil pressure sender is on the engine as I'm liking the idea this is a wiring problem first off. I have the Diesel manual but it is silent on the location of the sender unit from what I can see.
3) Would the oil pressure drop that suddenly if there were a real problem with these engines? I'm used to seeing a rapid but marked tail off on other engines (BMW's) not a sudden drop as when the engine is turned off.
4) any other pointers that you can think of would be greatly appreciated.

Model is a Cherokee XJ
Year: 1998 S plate
Engine size: 2.5
Fuel type: Diesel
Trim level: Limited

Oh...when is the next midlands pub meet.  :icon_winkle:

Title: Re: Oil pressure gauge HELP
Post by: Bubba on August 20, 2010, 09:20:33 PM
fit new o p sender they are known to fail
Title: Re: Oil pressure gauge HELP
Post by: GREGBLACK on August 20, 2010, 09:23:57 PM
Hi I would think it a wiring connector fault at the back of the guages, you have shook something loose going over bumps, my Cherokee 2.5td does this as well and I am fairly certain thats what it is.
cheers greg
Title: Re: Oil pressure gauge HELP
Post by: Mike Pavelin on August 20, 2010, 09:26:31 PM
It's the sender unit. They're as durable as a chocolate fireguard. It's under the middle of the manifold assembly behind the turbo. Good luck.
Title: Re: Oil pressure gauge HELP
Post by: brick on August 20, 2010, 11:06:42 PM
Cheers gents.

Deep joy awaits then if I need to change the sender.  :010:

I think I 'll go for messing with the dash first even though my gut is telling me sender. Sods law says if I went for the sender first it would laugh at me and just be a dash connection and then how silly would I feel.

Any pointers on digging out the turbo once I've finished with my adventure in hope over experience with the dash fix option? Just been to look at it properly and it looks very, erm...confined down there!
 
Title: Re: Oil pressure gauge HELP
Post by: MOCAJ on August 21, 2010, 06:51:26 AM
dont bother with the dash, it will be the sender

i had exactly the same symptoms and its an easy job  :greggmo:
Title: Re: Oil pressure gauge HELP
Post by: Dave69 on August 21, 2010, 08:46:25 AM
not the dash as it will be purely coincidence that it responded after you hit it.

pressure sensor is at the front left hand side of the engine by the oil filter take off, replace the sensor, a bit fiddly but should take 20 mins tops.

keep the old one as there is a thread on here how to take them apart and possibly reapair them.
Title: Re: Oil pressure gauge HELP
Post by: gazjeep on August 21, 2010, 09:56:34 AM
Oil pressure gauge did the same scary shit to me on my XJ, change the sender  :icon_winkle:
Title: Re: Oil pressure gauge HELP
Post by: brick on August 22, 2010, 11:03:01 PM
Cheers again gents.

Spanners out tomorrow then and start messing. Just Google'ing where to get a new OP sender.
Title: Re: Oil pressure gauge HELP
Post by: Dave69 on August 23, 2010, 08:41:31 PM
try lighthouse as the same type are fitted to all models
Title: Re: Oil pressure gauge HELP
Post by: brick on August 24, 2010, 12:45:40 AM
You mean these guys? http://www.ampar.com/lighthousejeepparts.html (http://www.ampar.com/lighthousejeepparts.html)


Got the following odd email back from my question about supplying one. Looks like it may be the dealer then.

Quote
From: Lynda Francis <sales@ampar.com>
Date: Mon, 23 Aug 2010 14:16:02 +0100
Subject: RE: Form Post from Firefox

Good afternoon

Thank you for contacting the AMPAR Help Desk

Sorry we cannot supply the oil pressure sender as it is for RHD only, you
will need to contact a Chrysler Dealer.

Regards
Lynda
AMPAR


I gave them my car details... honest!
Title: Re: Oil pressure gauge HELP
Post by: Nosebolt on August 24, 2010, 01:09:50 AM
no that's not lighthouse, thats AMPAR, Lighthouse don't do any sort of electricy mail, its carrier pigeon or old fashioned phone call I'm afraid
Title: Re: Oil pressure gauge HELP
Post by: Panic mechanic! on August 24, 2010, 11:36:37 AM
this is their phone number but  don't be surprised when they don't answer using the name Lighthouse as its basically a farm
01953 681237

you will get the part next day tho but you can get them to send it normal post if you are in no rush,
Title: Re: Oil pressure gauge HELP
Post by: Bubba on August 24, 2010, 08:51:03 PM
ampar is simply a group of listed companys that suply parts fo american cars it is not a suplyer itself
Title: Re: Oil pressure gauge HELP
Post by: GREGBLACK on September 01, 2010, 06:55:02 PM
"pressure sensor is at the front left hand side of the engine by the oil filter take off, replace the sensor, a bit fiddly but should take 20 mins tops."


Sorry it was located there on the earlier  2.5td but on your 1998 it is under the inlet exhaust manifold and above the starter motor at the rear of the engine, I don't think you could do it in under 2 hours as it is virtually impossible to reach or see it without stripping parts off to get access.
Sorry for the bad news, I still have not done mine because I can not find an easy way andit looks like either the starter or the manifold has to come off. I hope some one knows better(please!!!!!)
cheers Greg
Title: Re: Oil pressure gauge HELP
Post by: Mike Pavelin on September 01, 2010, 07:55:19 PM
It's the sender unit. They're as durable as a chocolate fireguard. It's under the middle of the manifold assembly behind the turbo. Good luck.
    Like I said....  I seem to recall you can get it from above with a crow's foot between the branches of the inlet manifold.
Title: Re: Oil pressure gauge HELP
Post by: Dave69 on September 01, 2010, 09:07:32 PM
the mk1 diesel has one benefit then  :icon_super:
Title: Re: Oil pressure gauge HELP
Post by: wildrover on September 03, 2010, 05:10:15 PM
My diesal Cherokee does the same trick with the oil pressure guage , but i am so busy repairing all the other problems on the Jeep , that this minor irritation is way down the list...

I was just about to get around to replacing a pushrod that got a bit bent the last time a hydraulic adjuster fell to bits , when one of the rear springs fell to bits...

I really don,t know why i love this car......but i do..!