Distributor Noise

[HOrnbrod]

Until you swap in the correct ECU you can't rule out a bad ECU, as you know Tom. Either the 56027396 (w/o RFI) or 56027418 (w/RFI) is correct for your 92 I6 manual trans, according to my manual. Compare the pin differences on the 60-pin connector between the auto and manual tranny ECUs using your FSM and see if something jumps out. Rather than rebuilding your existing one, I'd rather try a used one for less $$ to see first if it cures the problem or does nothing. There are some on Ebay. Seems like you have eliminated everything else............

[Exgrayxj]

Not trying to be a wise @$$, but have you considered that the replacement dist may have a problem? I would stick the chirper back in just for a trial.

I know the feeling... :wall:

 

 

Couldn't resist, Hornbrod

[flint54]

To Don, Yes I knew it was a long shot on the ECU swap, but it cost very little. I looked at the FSM

schematic beforehand, there's only one pinout chart for both manual and auto, and for MJ they differ

by only one pin. The auto has a neutral sense input (pin 30) that the manual does not. There are

two other differences (pins 26 and 46) but they're XJ with security module only. I figured it was worth

a try. I've got an Ebay 396 ECU on the way here now.

 

To Exgrayxj, All recommendations are most welcome. I'm not sure how the distributor could be a player

in this issue, but it would be a simple enough test. I'm going to soak it in penetrant for a good long while

and I think the chirping will resolve. The innards are gummed up (like an old carburetor bowl) and solvent

should undo.

 

Yesterday I looked at an OEM intake gasket, and it appeared to me a lot more substantial than the Felpro

I used during the intake swap. So, I replaced the intake gasket to rule out an undetected leak. (BTW

I asked the dealer, just for grins, what they would charge. They said $90 for parts plus 5.5 hours labor.

I got the OEM gasket for $20 and completed the job in less than 3 hours). The removed Felpro gasket is

unusual in that it appears as if some fluid (fuel??) has soaked around, and outward, past the sealing region

of each intake port. After a 24 hour retorque, plus an engine hot/cool second retorque, there are no changes

of symptoms.

 

My local Jeep shop (Jeeper's Den in Orlando - great folks), suggested I monitor fuel pressure through the RPM

range and look for dropout. They're thinking starvation at higher RPM's. I did that today, and fuel pressure

remains steady at ~32 with increasing RPM, up to, and beyond, engine getting ratty. If I blip the throttle

quickly, fuel press spikes high (~40) corresponding to the momentary vacuum drop. All seems well here.

 

If things don't improve after the next ECU swap, I'm tempted to just drive this thing up to the folks in B-ham

and let them sort it out. My bag of tricks is nearly empty.

[HOrnbrod]

To Don, Yes I knew it was a long shot on the ECU swap, but it cost very little. I looked at the FSM schematic beforehand, there's only one pinout chart for both manual and auto, and for MJ they differ by only one pin. The auto has a neutral sense input (pin 30) that the manual does not. There are two other differences (pins 26 and 46) but they're XJ with security module only. I figured it was worth a try. I've got an Ebay 396 ECU on the way here now.

 

If things don't improve after the next ECU swap, I'm tempted to just drive this thing up to the folks in B-ham and let them sort it out. My bag of tricks is nearly empty.

 

AAARG. Figured the NSS signal was the only ECU difference. Hope I never have this problem, and I bleed for ya mate. Hope the "new" ...396 ECU does it for you, but I have doubts now. If you bring it to Hesco (assume that's who you mean), first thing they will probably do is put her on the dyno and run A/F curves vs. HP/torque curves and look to see at what RPM all turns to crap.

 

I know you have looked at the plugs, but what you should have in there IMHO is the old school solid copper core Champion plugs, Champion RC12LYC. I have always used these in my I6 Jeeps, experimented with many others, but they always worked the best. I use the same in plugs in the stroker, although two heat ranges lower.

[flint54]

"the old school solid copper core Champion plugs, Champion RC12LYC"

 

are exactly the plugs I'm using, and they're new (like damn near everything

else), of course. The auto parts guy tried really hard to sell me the fancy

platinum XYZ miracle plugs for $16 each, but these $2 Champions are all that

anyone really needs.

 

I'm going to be jeepless for the next month working in DC, but when I get

back I'm seriously considering limping this thing to Hesco. I doubt their

dyno goes low enough for the current condition. ;)

[flint54]

Well, things have gone from bad to worse.

 

Truck will no longer idle, and can no longer be driven either.

 

The latest changes:

 

1) I swapped back in the original distributor, after dismantling

and cleaning/polishing the shaft. No improvement, so I put

back in the new distributor. The old dist had several degrees

rotational freeplay of the rotor mounting plate anyways. Have

strong blue spark at all plugs. Absolutely certain that rotor is

aligned with #1 at TDC compression.

 

 

2) I swapped in the correct (396) ECU pulled from a running motor,

and no improvement. No fault codes either (other than 12 & 55).

 

3) I installed a new, OEM, CPS. Motor runs long enough to call this good.

 

4) I installed a new, OEM, coil. Have strong blue spark.

 

I can start it at half throttle, and it will rev between 3K and 4K (with some

sputtering) but as soon as I let off it dies. I can start at closed throttle,

and it will limp at about 200 rpm for a couple minutes.

 

Compression good, vacuum good, fuel pressure good.

 

There are no "smilies" to convey my status, but this one scratches the surface: :wall:

[flint54]

Yaaaaaaaaa-Hooooooooooo !!!!!!!!!!!!!!!!!!

 

The problem seems solved!! Lad over on the Hesco forum recommended

I check the cam sensor. When I looked at it closely, it appears as though

I had somehow pinched the lead. Don't know how, probably caught it under

the lip of the dist. cap. With this now fixed, the truck runs like a scalded

dog. OH MY GOODNESS do I have power now! Mountains of torque, and

revs cleanly to redline under full power. I hope this nightmare never happens

to anyone else, ever. Plus side is that I've got quite a box full of used

parts, many of which are probably still good.

[HOrnbrod]

:thumbsup: Glad you found it.

[HOrnbrod]

Yaaaaaaaaa-Hooooooooooo !!!!!!!!!!!!!!!!!!

 

The problem seems solved!! Lad over on the Hesco forum recommended I check the cam sensor. When I looked at it closely, it appears as though I had somehow pinched the lead. Don't know how, probably caught it under the lip of the dist. cap. With this now fixed, the truck runs like a scalded dog. OH MY GOODNESS do I have power now! Mountains of torque, and revs cleanly to redline under full power. I hope this nightmare never happens to anyone else, ever. Plus side is that I've got quite a box full of used parts, many of which are probably still good.

 

Was just over on the Hesco forum and I noticed who answered your distributor question, Cheromaniac. That's Dino, Doctor Stroker hisself. Good guy. Probably knows more about strokers than anyone, except for Hesco's Lee Hurley. :cheers:

 

http://www.angelfire.com/my/fan/