2000 XJ classic, 4.0/4WD

I washed my engine(I know, bad idea), sprayed it down with an engine degreaser, let sit for 15 minutes, then sprayed off with a garden hose in the driveway. After rinsing it started up just fine, pulled to other side of the driveway to rinse the gunk off the gravel. I washed on Friday afternoon, it is now Monday and I still cannot get the thing started. I have replace the spark plugs and ignition coil packs, pulled apart all electrical connectors and hit with WD-40 and packed with dielectric grease. Completely dried out Cam position sensor and Throttle position sensor. Engine will crank really strong, until the battery runs down. I have had the hood cracked and a fan on to dry things out.

I am at a loss, what to check next, what needs to be replaced, and what are some tips and tricks to get it started. This xj is my daily driver and I need it back on the road ASAP.

Thanks

 

1. Do you have spark?
2. Do you have fuel?

 

Don't look over the simple things like fuses. Mine did that one time after engine work and for some reason the fuel pump fuse was blown? Replaced fuse and been fine since.

 

yeah give the fuse box a once over. Fastest way is with a multimeter set to ohms and check continuity over the 2 exposed metal portions of the conductor on top of the fuse. Then you dont have to pull each individual fuse. Just do it with the battery disconnected to ensure there isnt ANY stray voltage going through to give you a false reading. Or at least do it with the key out of the ignition....

 

I am getting fuel, I assume that it is a spark issue because I cannot get it to fire even on eather

 

The fuses all look good, that was my first thought too

 

1996 XJ 242 After replacing my radiator last year I washed the engine down and had a really long crank to start. Forgot the engine code I got from the key switch, but it was something funky with the fuel pump relay. Replaced relay, cured code and started fine after. Never figured out what tripped that, or if it was just a coincidence.

 

I’m not a fan of washing engines unless there’s good reason such as to clean a mess made while doing repairs that could cause smoke or fire or to clean up simply for appearance to resell . If you have to wash it leave it running and avoid spark plug wells and distributor/wires.

 

I had the same thing happen when I degreased my jeep a few years ago. I replaced plugs, wires, cap and rotor and it fired right up. In my experience most of the time it's something simple that's getting overlooked. I agree with others that if swapping parts doesn't fix it you'll need to start at the basics 1) see if your getting spark 2) see if your getting fuel and back track from there. Last suggestion is to check your grounds - make sure those are moisture free.

 

I feel like taking a common sense route to washing your engine should be taken. Not that you didn't take precaution...
Don't spray anything directly on electric connectors, especially if its going to be high pressure i.e. coming out of the water hose or anything higher psi than that. That's about the gist of that.
I normally spray the engine block with degreaser where its real dirty and oily, then use a non-direst spray approach to everything else. Kind of a mist enveloping everything on top of the engine bay, letting it lightly settle on stuff. let it sit for a minute or 2, then use the mist setting on the water hose gun to lightly rinse it all away. NOTHING high pressure.

 

I haven't had any issues with just disconnecting the battery and placing a plastic bag over anything I'm concerned of.
Everybody has their own way of washing an engine.

 

Disco' of the battery sounds like a decent plan. Ensure nothing can short out with the power still hooked up.

I would say a good follow up step is to leave it disco'd and let everything dry out decently then hook the battery back up.

So washing your jeep in the evening on a friday or saturday so you can leave it unhooked and dry overnight.... then hook it back up in the morning.

Or I suppose any night if you dont mind hooking that battery back up before you head to work...

 

I do that as well, forgot to include that.

 

Update: I have replaced IAC, MAP, TPS, "distributor" (whatever our alternative is called), cleaned grounds to bare metal, installed new battery terminal connectors, on top of the coil packs, spark plugs done previously, as well as leaving the vehicle in the sun, hood open, with a fan to ensure that everything is dried out. I have been adding one part at a time then trying to start, testing for spark, etc. After putting everything on, I remembered that my negative battery terminal is boogered up so I replaced the positive and negative terminals. Engine cranked, sputtered, and died on eather. I took this as a good sign, and kept trying to start. It is trying to turn over about 50% of the time, but still not running. I have done a lot of reading and have come to the conclusion that it may be the Crankshaft Position Sensor, am I off-base?

 

Yes.

You are throwing a lot of expensive parts at it and I haven't seen anything about testing any of it.


CPS is a likely suspect. You should TEST it.