Help Wanted Part 2

[Rob Mac]

Thanks to Robyn & Phil for answering my Query.
The motor is still missing under load.Have tried disconnecting & reconnecting battery,it runs good for 1 minute,then stalls. On restart it runs rough again.Have tried doing code with accelerator & brake,but it does the same thing.The codes I am getting are 17,18 & 54. When under load & breaking down it blows a lot of black smoke.The motor was recently reconditioned.
Any Ideas???

[Robyn]

The code 17 is "High resolution sensor"
Code 18 is pump cam reference pulse error
At this point you really need to get the rig scanned with an OBD1 scan tool to see just what is going on.
There could be a problem with the pump or a wiring problem.
try checking the Noise suppresion harness where it plugs into the top of the IP
This is a 6 wire plug (rectangular) that plugs into the little black aperture in the very top of the pump. The plug faces the back of the engine.
This harness has a little black box thing in the center of it that the wires go through and then the harness plugs into the main engine harness that routes under the intake manifold.
Clean connections are very important on all this stuff.
*** caution*** these connectors and their little latches become brittle over time and can "Go Away" if you get too rough on them.

The main engine harness plugs into the body harness at the back of the engine. If the equipment was put back properly when the engine was rebuilt the harnesses all clip into a bracket behind the fuel filter.
Check the two (2) largest plugs back there to be sure they are secure.
You may want to try unpluging them and spraying them with electrical contact cleaner and reconnecting.
The two small plugs are for the fuel filter assembly ( water in fuel and fuel heater ) Dont worry about these


There is a drawn out procedure for testing the system but Unless you are familiar with the system to some degree I think it would be wise at this point after checking for dirty or loose connections to have the rig scanned with an OBD1 to see whats going on.
A code 54 does not seem to show in the factory listing, please check the coce number and get back. There is 51, 57, 64 and a few others but not 54
A bad connection can louse this stuff up big time. also be sure the grounds at the rear of the engine by the tranny dipstick are in place. If you have a broken ground to the engine from the main harness you can have all sorts of goofy things going on.

The small noise supression harness I spoke of earlier has been known to cause grief and can be the source of trouble but they are pricey so to just replace it I think would be remiss at this point.
On my recent rebuild of my 94 I replaced all the engine harnesses just be to be sure of not having trouble down the line as it was all off the engine anyway.
Good luck and let us know
Loads of smiles and a zillion miles
Robyn

[tommac95]

Rob, you've got some good advice above, but some more questions here:

Any idea what 'recondition' means/meant?
It is common event that following installation of 'new head gaskets', 'rebuilt heads', or even 'new heads' , that the firedeck/cylinder-block/head sealing surface wasn't refinished [easy not to if job done while block in truck] and thus cylinder doesn't seal well; similar/worse scene with poorly rebuilt heads.
It is common event that following installation of new/rebuilt injectors, that some dirt in line, or air entrapped, screws things up a bit.

I would suggest make a determination as to whether the problem is fuel/electric/mechanical in nature.... i'd get a good compression test done if you really don't know what's up--if the compression is good, then you have something good to start with [like pistons/cam/valves/heads are ALL presently working, OR NOT]. Then you can decide whether to move forward to deal with fuel/electric issues , or move backward to address fundamental mechanical deficiencies. This can also be valuable as a benchmark to test against at a later date, to assess wear going forward. A scan may well also clear up many issues; the codes suggest the FIP isn't real healthy. For that matter, you might want to 'crack' open the union nuts on each injector {cover withg rag / wear eye protection} in series, progressively observing to see if fuel is reaching each injector.