Code 27 Intermittent hesitations, power loss, stall

Hi everyone,
I own a 93 xj with the 4.0 h.o. and for a few month its been having some intermittent power loss after crossing rivers, water puddles or washing the car underneath.

After a few minutes after running into water, The car wants to die and when I hit the gas at some point it'll kick back and run perfectly smooth... One time it stalled... It can do that (almost die then revive) for 5 or 10 minutes after water crossing and then run perfectly fine for hours.

It also often does that after a cold start. But always start.

The code 27 is displayed. Do you have any idea of where to look since this is water related ? The injectors wiring never look wet. It never does that when i'm on dry trails or highway except cold start but it vanishes after a minute...

Thanks for the help...

Distributor can be sensitive to moisture like that. I had something similar in dense fog when the cap was getting old.

Hi

I still have the problem and it's getting worst. Now it's not only when I run into water but for a long time after a cold start or randomly when driving.

At some point, it starts to sputters, seems like bad misfire (multiple cylinder). No acceleration at all and then take off. When at idle, it will starts to have very low idle, misfire, backfire through intake and at some point, will rev high and run smooth and will or will not start again to run rough.


What I've done :
- Full tune up (helped but problem not fixed)
- tested map sensor (2.2v cold idle, 1.8v hot idle)
- tested grounds (good), cleaned them and connected the ground point near the oil pressure sending unit to the battery negative
- checked for vacuum leak, nothing obvious
- checked IAC, operates to adapt idle when going low (until it starts to rev high and then go back smooth at normal idle)
- Cleaned IAC and throttle body
- Checked TPS, good
- Checked fuel leaks and FPR, all good
- Checked injoctor (feel by hand) some feel way stronger than others...
- cleaned battery terminals and replaced battery connectors


My ideas :
- Injectors getting stuck intermitently
- Intermittent fuel pump struggle (never cut off when problem is occuring)
- water in fuel (I run e85, it's been 2 years)
- yet un-spotted vacuum leak
- CPS intermittent problems ? (fuel gauge and voltage does not fluctuate when probleme is occuring)
- possibly NSS killing ignition randomly ?

I don't know where to look for to continue my diagnostic and don't want to throw random parts at it.

If anyone have any tests I could run to pinpoint or dismiss any fix possibilities, that'd be awesome...

Thans in advance...


PS : I run e85 on multiple vehicle and never encountered problems like that but I'm going to try putting a tank of 95 to see how it goes.

PS2 : I've run the jeep without o2 sensor for the past 2 years and 20k without any issue occuring.