Diagnostic Now....Broke XJ shaft, melted rotor. Cause?

[Blue85]

A bad connection explains the heat and the dead modules.

The peak power from the coil is quite large, but the average power is low. However, when you can't get rid of heat even a small amounts cause high temperatures eventually. I shared my story of the carbon button melting everything and a lower resistance version being reliable. But you have to remember that arcing is very hot - like fire.

If it's arcing, the electrical noise is huge and could damage the module.

 

[dhcomp]

WTF. new distributor, running great. Idles fine, wot, everything. On freeway, the thing that made it die the last time was shifting from od to neutral, then back into od. Figured i might as well see what happens again and figure out If it's really fixed. Motor stumbled, then shut down. Won't restart. Sounds like timing is off. Distributor is tight, rotor is fine.

Am I just skipping a tooth on the timing each time I do this, or what? Waiting for a tow again .

 

[y5mgisi]

Geesh! I REALLY dont think you are skipping teeth at this point. First off, you wouldnt skip and then have it skip back. It would skip once and be lights out until you fixed it. And definitely not with how tight you said the rotor movement back and forth was. When you replaced the distributor this last time. Did you disconnect the battery?

 

[dhcomp]

Um, not sure. Probably not. Would it really do anything if the ign was off? Theres no constant hot going to the distributor.

Will verify if I'm getting fuel when I get home. If I'm not, possible voltage spike killing ign modules?

 

[y5mgisi]

Possible. Reason i asked was that maybe the OD-N-OD was freaking out the computer and causing it to shut itself off for whatever reason. Then, when you un hooked the battery, it reset itself and allowed it to run again. Its too bad that you cant just do the 6.0 now!

 

[dhcomp]

Possible. Reason i asked was that maybe the OD-N-OD was freaking out the computer and causing it to shut itself off for whatever reason. Then, when you un hooked the battery, it reset itself and allowed it to run again. Its too bad that you cant just do the 6.0 now!

I've thought about it! Haven't done te research yet abt the 4l80e and the ac.

 

[dhcomp]

Ok, so I took off the cap/ rotor to inspect on the side of the road. All looked fine.

Towed home. Check for fuel at injectors....no fuel. Go to check ign module connections, and realize wires fell off the coil (broken clips). Reinstall, fires right up.

Really doubt these fell off while driving, more likely that I knocked them off while checking the rotor. Only other thing I did was momentarily remove the ECM fuses. Wierd.

Drive it about 40 miles, including the dreaded od-n-of shift a few times..... No issues.

Wtf. Glad its working, but nervous now...

 

[y5mgisi]

Thats pretty wild man.

 

[imiceman44]

You are one lucky mother fockker

Remind me not to get too close to you.

Ok, so I took off the cap/ rotor to inspect on the side of the road. All looked fine.

Towed home. Check for fuel at injectors....no fuel. Go to check ign module connections, and realize wires fell off the coil (broken clips). Reinstall, fires right up.

Really doubt these fell off while driving, more likely that I knocked them off while checking the rotor. Only other thing I did was momentarily remove the ECM fuses. Wierd.

Drive it about 40 miles, including the dreaded od-n-of shift a few times..... No issues.

Wtf. Glad its working, but nervous now...

 

[y5mgisi]

In a way im curious (yet hopeful that it wont happen again) for it to happen again to see if next time, pulling the ecm fuses alone will get it to start back up.

Also i think i found the solution! Dont shift into neutral on the freeway!!! LOL im sorry, just had to say it.

 

[dhcomp]

Thinking maybe the coil wires did fall off to cause it last night. No idea. Ordered new plugs with non broken clips.

Ran fine all day today!

 

[y5mgisi]

Awesome! Do you think the fuel economy and slight power loss you had mentioned a while back is gone now too? Or is that still there and possibly caused by the afpr?

 

[dhcomp]

Awesome! Do you think the fuel economy and slight power loss you had mentioned a while back is gone now too? Or is that still there and possibly caused by the afpr?

No idea. Still sorta stumbles and loads up when i wring it out 15 seconds plus....

Turned down the fuel pressure to 12ish, i think.

Gotta decide if i drive it this weekend to shasta. If i do, i'll know for sure.