93 zj nightmare

jbbiggs67 did pass the time by typing:

It would have been easier just to replace the distributor.

you actually turned the engine you shouldn't have had to re-index thedistributor.

... You know this now, but over-revving an engine that isn't working is the absolute wrong thing to do...

The 4.0 is a zero interference design so you can't bend a valve or rod.

12 (battery disco, check your battery cables) 24 Throttle position sensor input above or below acceptable voltage. TPS signal does not correlate to MAP sensor. 54 No camshaft signal detected during engine cranking 34 An open or shorted condition detected in the Speed Control vacuum or vent solenoid circuits. Speed control switch input below the minimum acceptable voltage 51 A lean air/fuel mixture has been indicated by an abnormally rich correction factor. (O2 sensor) 55 (end of codes)

What that's telling me is to check your battery terminals and make sure they are tight an corrosion free. Also double check the harness. All those codes won't set normally unless the power has been interrupted. Also check the Camshaft Position Sensor connector to your distributor and the Crankshaft Position Sensor Connector down by the dipstick.

In the event of a serious engine fault the ECU (engine computer) will prevent the TCU (transmission computer) from getting out of first. This is to help prevent extensive damage.

Depending on what went wrong it may be as simple as a forgotten connection or you may be looking at having to get the ZJ flatbedded into a shop.

Thanks Doug I was by myself and i installed the distributor and it would not fall into the oil pump, so i bumped the engine without the hold down in place, the distributor jumped up instead of falling in so thats where the fun began, Has anyone pulled the oil pan on these with the engine still inframe?

I have seen a 4.2 engine run when it was clocked 180 out. It sure didn't have enough power to get out of 1st and it made 'bad' noises for a new bottom end, but it ran.

Mike

86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00 88 Cherokee 235 BFG AT's

snipped-for-privacy@earthl>

Ok replaced the cam sensor and it fired right up. (took pictures this time before i removed the distributor) codes went away except for the 24, I looked at the connector for the TPS and it was wet, I am letting it dry out for awhile and will try it again. If OBD checks out I will replace the bearings this weekend and the oil pump.

jbbiggs67 did pass the time by typing:

Checking the TPS sensor is fairly easy if you have a volt meter.

with the key on, engine not running, backprobe the outer two pins and you should see 5V, keep the neg side connected and backprobe the center pin. Now slowly open and close the throttle plate.

The resistance should move smoothly with no jumps or drops and range about 1 to 4 volts, mine measures .748 to 3.8.

If you get some drops, take a few seconds to quickly open and close the butterfly then try again. Sometimes a crudspot develops and can be wiped off by exercising the throttle plate.