Got a 97 1500 5.9 on trade basically for free a couple months ago. 280k miles, trans case wouldnt engage, sloppy steering and popping felt in steering wheel.. but overall ran great. misfire codes and oil consumption but not terrible. rocker rust but spotless underneath

fast forward a couple weeks and i have to replace thermostat housing gasket, water pump just in case, and a seized brake caliper. battery craps out a few days later so that is now new

After using the truck to move, on the last leg of the trip it stalls coming to a stop. just shuts off. Im able to restart it in neutral right away. Does this several more times and im barely able to limp it home as it misses bad and sometimes cranks but no start

first things first i tore apart the top end. Discovered that previous idiot owner broke the distributor cap screw off flush in the distributor. the cap was zip tied on. and not tight. new distributor, cap/rotor, plugs, wires, coil.

gave everything a major cleaning and put back together w new felpro gaskets and bolts.

go to start and cranks but no start. code for intermittent loss of crankshaft position signal to pcm that i had seen before teardown. Replace w auto store crank sensor. starts right up and runs beautifully like i had never seen.. for one minute. Misses again, backfires through the intake and i hear a knock during backfire as well. shut it down.

recheck everything (cleaned iac and tested alternator). Does not start ever, only cranks

i unscrewed and unplugged the o2 sensor and it starts right up. cat was clogged. chop cat off (no o2 sensors now but at least it runs) w a muffler. but it only idles at 500rpm, misses like crazy and doesnt rev past 3k. Code still for intermittent loss of crank signal.

get it into the shop. they say timing is set at zero thru pcm and the fuel sync procedure after the distributor install seemed it might not complete the process w no oxygen sensors but after doing the procedure it runs no different.

only code im getting is loss of crank signal and missing oxygen sensors. it sometimes starts right up when cold. idles low and misses and backfires, sometimes light but constant, but sometimes really bad

i checked grounds and wires. wiring harness looks brand new. multiple battery ground on/off cycles w no help.

at open throttle besides zero power the symptoms fade

have not checked fuel but seems to be good. will test compression tomorrow when i get time

idk if i consider the thing a loss and just burn it or find a different motor. Found a 98 5.9 w 88k and w intake off from pictures it looks really clean compared to mine. my fear is putting another motor in and having the same problem anyway like my worst nightmare. i dont know if this truck is worth all the time money and frustration, even w only a couple hundred bucks into it total

will post a list of what ive replaced or fixed when i get a few more mins

 

Have seafoamed it twice after putting back together before changing plugs as a hail mary. no help but some smoke. if it were a fuel problem i think itd stall while driving but doesnt now. the crank signal code is my big indicator but idk wtf

 

OK. TIme to slow down and breathe slowly. I suspect that due to what appears to be significnat neglect, you have sevearl issues that when compounded, become harder to diagnose as they overlap syptoms.

Do some simple things first.

What do you mean by "tore apart the top end." Exactly what did you do and how did you do it? Did you replace the plenum gasket?

Check fuel pressure just to veriffy it is good so you can eliminate this as a problem.

Disconect battery and remove IAC from throttle body. Clean it (do not turn pintle) and clean the port it came out of very well. I know you already did this, ut check the port. It is easier if you remove TB. Reinstall in clean port.

Order new Denso O2 sensors and install.

Behind the head on the pass side, there is a crank sensor. Two screws. Pull it out and check it. Is there pices of anything on it? If so clean it off. If it shows rubbing on end, replace it.

Check plug wire routing per TSB in the FAQ/DIY section. Have you downloded the manuals form that section yet?

Connect battery and try again.

 

Compression test numbers might help decide whether you want to invest more time and money.

 

Took off everything down to heads. lots of carbon everywhere. left the heads (dirty but nothing loose or stuck) and put a little seafoam in the crankcase. cleaned out the throttle body and intake plenum/pan/runners. Installed plenum bolt and gasket set. also the intake/tb gaskets, replaced cracked vac lines, complete new ignition. Injector o rings

already cleaned iac and bore. brand new crank sensor.. i know where its located..i just put one in.. it ran the best it ever has for one minute. i can check for some sort of damage but what could cause this?

i have every manual i can find or download besides chiltons. will check fuel pressure and compression tomorrow

did i mention the plugs and wires that were in there when i got it supposedly had 40k miles on them without plugs even being gapped.. some ppls kids

 

Not all crank sensors are created equal..... Have a look at it, and see if it is damaged. Wouldn't be the first time one wasn't quite right, and got ate up by the flexplate...

 

This is very true. I had a to replace my crank sensor when doing the tranny in my 96 because i pinched the wires for it. I bought a NAPA sensor and had all sorts of problems with it. It took six monthes of testing to figure out it was the crank sensor because i never got a code when it would act up. Finally I got same code you have and bought an OEM sensor and have not had a problem in 4 years.
Also try clearing the codes in the computer first and see if that code keeps coming back.

Dave

 

If you're gonna burn it let us know where the fire will be. I got some hot dogs and marshmallows.

 

Yeah, but, the burning rubber, and assorted other chemicals gives 'em a bad flavor.

 

Its always worth fixing....its probably something small and easy to fix...id try a new crank sensor like stated above