Post water flooded renix help

so i sank my 88 renix MJ into water, getting it running again isnt going so well. as you renix gurus can imagine the water damage is really wreaking havok on the renix electrical system.

i was able to get it running again, but only for a short time. heres a list of things i did immediately after:

cleaned all grounds
cleaned all electrical connections
swapped in my spare 89 renix ECU
new cap and rotor
cleaned all terminals for relays and replaced bad relays
new alternator
new ground cable to the dipstick tube
ran a separate ground cable from the battery to the critical grounds that attach at the dipstick tube
new IAC


maybe im forgetting something but anyways here are the issues.

she ran and drove for a day and now she wont start again. the first issue i noticed was it would jump up and idle at 2,000 rpm and slowly climb to 3,000 rpm. thew in a spare IAC and it still did it, but after about 60 seconds or so it adjusted down to about 1000 rpms @idle. eventually that one would just stay at 3,000 rpms so i put in a new IAC. upon first start up it reved to 3,000 rpms for about 30 seconds and then idled normally. strange.

now the main issue. after driving it for about 10 minutes after getting it running for the first time, she just died at a stop light. towed it home and started diagnosing. no fuel pump and no spark. i was getting power to the ICM, but the fuel pump still wasnt cycling.

after leaving the negative battery unhooked for awhile i randomly tried to start it again and what do you know, she fired up. so i drove it again to find out maybe what happens before it dies. after hitting a rough section in the road she cut out again, just like the first time. towed it home and same symptoms, no fuel pump cycling and i still have power to the ICM. after leaving the battery unhooked over night it didnt magically fix the issue like the first time. the starter relay occasionally was acting up during my diagnosing, so i put in a new one. all of the issues still exist.

so i believe the issue occurs because something is getting rattled apart, due to the rough road killing it the 2nd time around.

other information i've collected:
i have 2 extra ICMs that ive tried and i still cant get spark
ive tested the signal from the CPS and its good.
the fuel pump will work if i hot wire 12v to it, so it shouldnt be bad.


what says the renix gurus? i keep going through and checking all grounds and all connectors, they all seem to check out. what am i missing :dunno:

wow, didnt think id figure it out, but i just may have.

i triple checked the wiring on the starter relay. i had originally arranged them by the labels on the relay itself. then i double checked by looking at a diagram online and it had the ignition and ground wires reversed. i said what the hell and switched them, even though the labels on the relay said otherwise. that got her started again, so i was able to find out what connector is cutting out.

the CPS turned out to be the cluprit. i barely picked up the connector and it cut out and died. so i hardwired it together, and it worked great. but i tugged on the wire itself and as soon as it caught the CPS itself it cut out as well. so i need a new CPS. hopefully this will cure the issue.

The starter relay,the relays on the relay block and the TPS are all poorly sealed. I've taken my starter relay apart and found it mostly full of dried mud. And have blown out the relays from the relay block with air and had an amazing amount of water come out of them.

It doesn't take much water to screw up a TPS and a very high idle (especially at start up) is one of the outcomes of getting it wet.

You really have to blow out the bottom of the distributor with air. Moisture gets under the cam position sensor mounting plate. It doesn't take much moisture after the motor gets hot, for the water in the bottom of the distributor to turn to vapor and short the cap from the inside.

Water gets inside the starter and coats everything with muddy water, when the water dries it leaves a coating of mud/dirt that can cause cranking issues.

Just a few things I've learned the hard way.

At one point, a few years ago, I had a renix that wanted to be a submarine instead of a Jeep.
After driving me crazy with random starting/running issues, I too found the starter relay is not in any way "sealed". It had an amazing amount of crap inside of it. Swapped it out, all was fine after that.

Thanks for all the advice guys.

so this explains a bit:



crappy pic, but basically the wires from the CPS are exposed and were touching each other, causing it to shut off obviously.

all is well now, the high idle at start up seems to have stopped as well. hopefully nothing new comes up

Note from DJ
You might want to check the fluids in your transmission, transfer case and both differentials for water.

They all have elevated venting tubes which may have broken from old age which allowing water in.

Already got that part covered. Changed the diffs, t case, engine oil and still working on the trans. Ive put about 6 gallons through it and its just about back to normal

cheapcherokee93 said:

wow, didnt think id figure it out, but i just may have.

i triple checked the wiring on the starter relay. i had originally arranged them by the labels on the relay itself. then i double checked by looking at a diagram online and it had the ignition and ground wires reversed. i said what the hell and switched them, even though the labels on the relay said otherwise. that got her started again, so i was able to find out what connector is cutting out.

the CPS turned out to be the cluprit. i barely picked up the connector and it cut out and died. so i hardwired it together, and it worked great. but i tugged on the wire itself and as soon as it caught the CPS itself it cut out as well. so i need a new CPS. hopefully this will cure the issue.

Click to expand...

Click on the following link and see posts 7 and 27. Make sure the CPS wires are routed correctly.

http://www.cherokeeforum.com/f51/cruiser54s-mostly-renix-tips-153657/

alright so she runs great now! although now the idle problem is coming back. stays at 3000 rpm and wont come down. i have to shut it off and start again until it decides it will idle at normal speed.

what should i be checking?

cheapcherokee93 said:

alright so she runs great now! although now the idle problem is coming back. stays at 3000 rpm and wont come down. i have to shut it off and start again until it decides it will idle at normal speed.

what should i be checking?

Click to expand...

Sensor ground test and TPS adjustment if that passes. TPS replacement after that. They hate water.

What cruiser said, but have you tried to disco the TPS and see if it idles normal?

Johnnie Walker said:

What cruiser said, but have you tried to disco the TPS and see if it idles normal?

Click to expand...

Good idea also.

But don't skip the other stuff.

alright so an update.

passed the sensor ground test, so i went ahead and put in a spare TPS i had. adjusted it per Cruisers write up and so far so good, no high idle. Hopefully it stays that way

cheapcherokee93 said:

alright so an update.

passed the sensor ground test, so i went ahead and put in a spare TPS i had. adjusted it per Cruisers write up and so far so good, no high idle. Hopefully it stays that way

Click to expand...

Those TPSs are finicky enough without having water on them!!