99 XJ wont start

Today i decided to put some rubber undercoating underneath and on the rockers of my xj to prevent rust and keep it protected. I sprayed the whole underbody and most of the body with a powerwasher so i would have a clean surface for the rubber undercoating. I had the radio playing while i was doing the undercoating and then i noticed it shutoff and i had killed the battery. no big deal. so i hooked up the battery charger for awhile then when i went to start it then it wouldnt start. it cranks at regular speed but it just wont start up. Now im wondering if it could have somehting to do with when i washed it. What is your opinion on this and what do you think i should try next?

Maybe you got the ignition wet. check plug wires and dist. cap (inside too). blow wires /plugs/cap dry w/ compressed air. First thing to check...next check for spark & fuel...

what would be the best way to check for spark and fuel?

I just checked the fuel using the schrader valve on the fule rail and it spit out a tiny bit and that is all. i took off the distributor cap and everything looks nice and dry. so is this a fuel problem? fuel pump maybe?

If you have an extra spark plug laying around, pull a plug wire and connect to spare plug. lay plug against engine block (ground). Have someone crank jeep over while watching for spark. Just don't try to hold it in place though (40,000 volts ouch !!!).IF you don't have a spare you could pull one of the plugs out and do the same. Fuel is easy, locate the bleed valve on fuel rail, (small schrader valve)- with key in run position, holding a rag over valve so that you won't get sprayed dispress valve for a split second to check for pressure. Make sure you do the spark ck first so that you don't have any spilled fuel around open sparks ! From what your describing I'd bet your wires are arcing out or you have moisture in dist. cap. If so, time for new cap/wires/rotor. If you don't have air compressor to dry wires try a hair dryer. Hope this helps

You will only have pressure if you try that test w/ key in run position. Also try spraying plug wires with wd 40 it displaces water.

Hey thanks alot guys. i pulled dist cap and looked dry inside, checked fuel and it looked good and checked spark and tat also looked good. once i had everything back together i figured i would try it again and it started so not really sure wut happened. maybe just a loose wire or the moisture dried up. idk but its fine now. belt squeaks real bad but thats about it.

A long time ago I made the mistake of pressure washing and not paying close enough attention to where al the water was going. So far you have got some good advice. I would also check the main computer connection. I fried part of my main harness and was causing a no start also.

A little trick I learned from watching the detail shop next to us clean engines is to preasure wash with the engine running and then let the vehicle run for a little bit afterwards until the heat from the engine drys itself. Just a little messy doing around the fan

bfred said:

A little trick I learned from watching the detail shop next to us clean engines is to preasure wash with the engine running and then let the vehicle run for a little bit afterwards until the heat from the engine drys itself. Just a little messy doing around the fan

Click to expand...

Just be wary of hitting the intake manifold with any diect spray, and try to minimize the indirect as well. The TPS doesn't like to get wet, and AFIK isn't really friendly to being dried out/rebuilt.