strange or oil pressure gauge problem limp mode help

[Mojave Jack]

Help...1997 ed 4x4 5.4 ...196619 miles, 2nd owner since 36k...intermittent problem becoming more frequent...a few months ago I was telling my relatively late 5000 pound travel trailer up the steep grade when the gauges all went bezerk losing oil pressure no voltage no fuel and overheating so I pulled over of course and uh kept it onto keep the fan going but then ended up turning it off and restarting it and the gauges went back to normal just fine. But now my gauges are doing the same thing more often and its even affecting the oil pressure light which I pulled over immediately check the oil and it was low and I added a quart.so as I am driving now the gauges will go to search except for the fuel gauge it'll overheat it'll go to zero voltage and no oil pressure plus the oil pressure light will come on but the fuel gauges find accurate I also will have regular power no additional sounds no problem idling but then eventually it'll go into kind of like a Limp home mode perhaps, so I find that I am putting it in neutral all the time turning up the car while its rolling and then restarting it so that it resets the gauges and gets me out of limp mode anyone have any ideas? oh and I forgot to mention that sometimes when the gauges first act up you can touch the break turn on the blinker and the Volt is dancing or the Volt meter is dancing with the electrical draw. when the gauges on phone turned me into a little pressure to vote me your and the water temperature go bad but without the oil light going on the car drives great and no limp mode is Experienced. any diagnostic impressions would help me out a lot thanks in advance dot dot dot

 

[Bowesmobile]

Does it happen to be raining or having had rained in the past day when this happens? If so it sounds like you have a windshield leak and its allowing the GEM module to get wet making your gauges go all wonky. Common problem. If your windshield is good I have had shops tell me they can re-seal the windshield for less money than replacing it.

 

[Mojave Jack]

thanks for the quick reply I am now at a mechanic but the original windshield is not leaking seems to be fine. However he is told me that my second radiator is leaking on the lower passenger side and we might want to put in a new water pump I don't know how this relates to a normal pressure light unless that gauge pod thing you mentioned it getting wet

 

[1997SCEBFEX]

This is screaming classic alternator replacement time from what mine did twice.
Go ahead and replace the serpentine belt twhile you're at it too.

PanHandler.

 

[Mojave Jack]

Awe so...Now that sounds about right. ...it is the original unit after 196k...thanks for that line of thinking....love this old gal...

 

[Mojave Jack]

Help Still Needed...Please...I used a sunpro charging system led gauge, headlights on ignition off, then headlights on ignition on...all checked out...more research and some thought oil sending unit might be bad...so spent hours getting to that thing (long post later with photos pending) changed oil fiter, test drove, oil pressure light still occurred limp mode occurred, put in neutral, off then on it reset and happened again, sitting in driveway I noticed brights on, both heaters cranked, and as I closed windows, the oil gauge was moving with the electrical draw...in fact holding the window button up even when it was shut appeared to reset the gauge problem and the oil pressure light was off too. Options from here seem to be: replace 100 alternator hoping; put mechanical oil pressure gauge test kit on sending unit hole to see actual pressure; pull oil pan to see if blockage is occurring in the oil pickup; ? Thanks for any advice...also...ac and heater havent worked for a while...blend door? but all other electrical seems ok...Help?

 

[xJohnnyOx]

Help Still Needed...Please...I used a sunpro charging system led gauge, headlights on ignition off, then headlights on ignition on...all checked out...more research and some thought oil sending unit might be bad...so spent hours getting to that thing (long post later with photos pending) changed oil fiter, test drove, oil pressure light still occurred limp mode occurred, put in neutral, off then on it reset and happened again, sitting in driveway I noticed brights on, both heaters cranked, and as I closed windows, the oil gauge was moving with the electrical draw...in fact holding the window button up even when it was shut appeared to reset the gauge problem and the oil pressure light was off too. Options from here seem to be: replace 100 alternator hoping; put mechanical oil pressure gauge test kit on sending unit hole to see actual pressure; pull oil pan to see if blockage is occurring in the oil pickup; ? Thanks for any advice...also...ac and heater havent worked for a while...blend door? but all other electrical seems ok...Help?

Mojave Jack,

Not sure if I follow. Did you replace the alternator as suggested by 1997SCEBFEX in an earlier post? Sounds like after all the checking you did not. If it is a voltage issue, and with vehicles of that age, you may have corroded wiring. If this is the case, you can clean the exterior of the terminals and still not get good voltage to the power distribution box. You may have to remove a bit of insulation near the battery connectors to see the extent of the issue. If bad, I believe you can buy replacement harnesses, or take off enough insulation and use a good battery terminal cleaning spray plus replace the connectors. If the wiring looks good, you may still have an intermittant alternator issue. I am always trying to pick parts like that from my local junk yard to have on the shelf for emergency use. Not too expensive that way.

Good Luck

 

[Mojave Jack]

Thanks xJohnny....didn't replace alternator yet, had it checked by a good mech I use, it did dip when he said it shouldn't, both ac on, brights on, over 14 volts with what he mentioned and intermittent alter problem, maybe...however...big news, I may have been following the oil when I should have following coolant...This is my theory...I towing up a long steep grade old engine, overheated, small leak in non motorcraft 2nd radiator created, temperature varies throught moths since, gauges go crazy because of cooling water/coolant; anyhow, I got a code of cylinder head overheat 1299 I think, so I put in two jugs of coolant/mix, and he erased the code, hasn't happened since, no dysfunction of any gauges, I also watched the water temp gauge like an eagle going up a steep grade that is on the way home that previously set the gauges crazy...so, if towing caused a small crack in cheaper radiator...that might do it...will keep informed and I want to post picto-ordeal of getting my fat hands on that sender where the plastic quick disconnect wouldn't release for nothing!

 

[xJohnnyOx]

Mojave Jack,

I know exactly what you are talking about in regards to the oil pressure switch. Here is my thread from last Oct. It may have been a blessing in disguise though, as I also found out the coolant was more of a sludge consistancy. I had just bought the 2000 E.B. Expy.

http://www.expeditionforum.com/f42/help-asap-please-oil-pressure-switch-21610/

The connector literally flew apart when I finally got it to come loose. The mechanic who replaced the oil filter housing (long story, read post), was able to take a matching connector that i picked at the salvage yard and just replace the chassis without having to splice in a new one .

 

[Mojave Jack]

Was almost there, secret weapon was the small hand of my 6 year old son...trying to unscrew, after grinding a custom size open ended wrench in 1 and 1/16th, shortening it with a grinder cut, but the wire was forcing the switch to spring back to previous positions, until three hands were used, the we had cut a customn wrench for nnnnnnes size of 13/16th for new unit and stuff...I tried to use a purchased o2 sensor socket removal kit, that have that great split on the deep socket, too deep...man, worked great with wrennches thnatn fit!!! Will post if proper coolant monitoring fixes...Thannks...keyboard nnnn is brokennnnnnnnnnn.....sorry for that

 

[Mojave Jack]

PS: I would have cut wire but zero extra wire in harnness to work with...

 

[Mojave Jack]

Just to let the forum know, has not happened again...feel somewhat foolish but lesson is to start with the basics...jeeze, just coolant level...oh well, if it helps others, cool

 

[Mojave Jack]

Okay, so embarrassed but it was the coolant level issue; if this helps someone then okay...I haven't had the gauges go crazy or any idiot light come on, even though it may apply in this case...lol, the lesson, just like the old timers said...start with the basics, battery, fuses, fluid levels...jeeze...took some great bags of gourmet coffee beans to the mechanic that did all those tests for free last Monday

 

[Mojave Jack]

Just to complete information: It is now been almost a week and no more gauge problems, in fact, she is purring like a kitten; have heat again; and my mileage has jumped from 10.1 to 11.8 mpg combined on the same job site routes...it is nice and quiet on the start up as well...oil pressure sender, examined throttle body, tubes to that intake, cleaned up negative battery cable...filled with coolant...lol