Greetings and much thanks to all in advance or any assistance. My name is Scott and I'm a long time reader but 1st time poster. I'll do my best to keep this short.

Continuing to have a stalling problem on my 96 Disco. It is intermittent and appears to only happen when proper operating temperature has been reached. 2 weeks ago in healthy snow and ice it would not maintain idle at all. Since I was in a brand-X auto parts parking lot I totally guessed and replaced the IAC valve to get me home. The IAC is not 100% flush as I snapped a mounting screw head and had to drill it out the remainder the next morning. I still need to find a proper fastener to shore that up as I did not do a perfect job but the o-ring looks sealed and it does have the appropriate gasket. I think that my be part of the problem. I pulled codes when I got home and I got back a P0125 so I replaced the ECTS. No real change in outcome.

Due to other performance issues and normal upkeep I had already replaced the CPS and have put in new spark plugs, wires and fuel filter.

I have never really learned how to use a multimeter. I usually just do stuff by basic diagnosis or searching RAVE or on the net like your outstanding forum. My question is do any of you folks out there think that the fuel temp sensor in the fuel rail may be at fault, low fuel pressure or the Multifunction fuel relay may be on the fritz? Freeway performance is great. No lag or hesitation in power and smooth delivery. Currently there are no codes as they have been cleared and it's too early to have reached it's drive cycle (I think). Hope this info gets me started. Cheers!

 

You can read the fuel pressure at the Scrader Vavle. I would recommend the correct screw on adapter. I had one go bad on me using a tire guage with a dial indicator. If it does go bad, you can unbolt it and replace it.

A multimeter is not too difficult with a little practice. Resistance is OHMS, touch the leads together, the meter should read ZERO. Apply the leads to each end of a circuit and it will give you the circuit resistance. Zero Resistance is a short, infinity or flashing value is open circuit.

The DC range will be used for checking things like battery voltage and such.


Hope this helps.

 

Fuel temp sensor is usually an issue on hot temp restarts. Fuel pressure can be checked with pressiure gauge on that tire fitting on the passenger side fuel rail (32-34 PSI, change fuel filter if lower, check vac lines to fuel pressure regulator).

So far you don't need to use the dreaded multimeter. Will be glad to help when that need comes along.

The multi function relay can cause all sorts of problems, but usually a failure instead of a once in a while issue.

 

THX Savannah. Also, I apologize for not posting in the correct place. TY for your patience while I learn to navigate. Never have belonged to any forum so I am indeed a NEWBIE.

My Disco does fire up fine after the stall. Right on key. Just dies when you let off of the gas pedal after running for awhile. Cold start idle right within range. I'll check the fuel PSI tonight and look to swap the fuel sensor ASAP. I will post results. Regards, Scott

 

If low PSI it will be filter or pump or fuel pressure regulator.

 

This sounds like classic bad IACV to me.
The multifunction relay will either work or not.
As stated fuel temp only effects hot starts.

 

Alright, sorry for the delay. Running ragged. Disco ran thru it's drive cycle and the CEL did come on again. Pulled the same PO125 even after I put the new one in. I swapped that unit with a spare I have in the shop so we will see on the AM commute if that effects anything at all.

As well I just went thru the ignition sequence in the attempt to reset the adaptive values of the IACV. Hope that it gets merry with the ECU.

I unplugged the MAF to check connections and reconnected. Then I unplugged the TPS and ran it for a minute or so. Foot was off of the pedal and it maintained a 2000 rpm idle and would not kick down. So I shut it down, reconnected the TPS and fired it up again. Same 2000 rpm but it kicked down on it's own when I put it in reverse. Again, we will see what is what on the commute.

I still need to check the fuel pressure at the rail (as I need to pick up the gauge and proper fitting) and did inspect the vacuum hose from the regulator and it is in fine shape.

It's also time for O2's again (Disco had 164k on it now) and ran flawlessly from new until 3 weeks ago. BLEED GREEN!

 

Oh, BTW does anyone have any good sources for non-evaps O2's. All-Foreign had them for $103 a pop forever (but of course when I REALLY want them they're out) Regards to all, SP

 

www.amazon.com

 

Hey Spike, OK to use Bosch universals? I've always been a bit confused between EVAPS and non-EVAPS. Are they not VIN specific? THX. SP