misterZ Posted July 25, 2009 Share Posted July 25, 2009 Here's the scenario: I was working on the car late one day and left the hood open overnight during a torrential rain so everything got soaked. The car started next day but ran very rough, spitting and sputtering. After some troubleshooting and drying things out, I replaced the cap/rotor, plugs and wireset with no change in running condition. Through process of elimination, I determined the #4 cylinder is not running as I can unplug the plug wire while the engine is running w/ no change (all others change pitch/running condition to worse). The last thing for me to check is the injector connector; all of them have cracked/split boots on the harness but prior to this happening the car ran perfect and strong. Is this the most logical cause of the problem? I've never messed with the injectors or wiring. [Edit:] Cleaned the connectors (a little corrosion), it's getting fuel--plug was wet and no sign of ever sparking (looks new out of the box but wet) so switched with the next cylinder and still have the same problem but now have narrowed it down to no spark at the #4 plug (same test as above). Going out for a stethoscope so I can hear things but sure all the injectors are firing. Plug wires are brand new and make good contact but haven't checked their resistance. Thanks in advance, Quote Link to comment Share on other sites More sharing options...
thetremendoustim Posted July 26, 2009 Share Posted July 26, 2009 same exact problem with me, except that I have it on 1,2 &3 cylinders Hahaha! However, right now I'm undergoing some homemade flow testing / cleaning my injectors Quote Link to comment Share on other sites More sharing options...
WildBill Posted July 26, 2009 Share Posted July 26, 2009 Did you check the spark to #4, or just unplug the wire & no change? I would make sure you are getting spark to the plug, if not, check spark out of the cap. Also, the injector could be working electrically, but not mechanically. You could verify spark and compression are good (just to be safe), and then swap the #4 injector with another cylinder and see if the misfire changes cylinders. But before you do that, make sure you have an injector pulse on #4 Quote Link to comment Share on other sites More sharing options...
HowlerMonkey Posted July 26, 2009 Share Posted July 26, 2009 All it takes is one good misfire event on some spark plugs to wet it enough that it refuses to fire until replaced.....or thoroughly cleaned in one of those sandblaster type spark plug cleaners. Not sure why but I've run into some plugs that never again fire correctly after being wet fouled. Really shouldn't happen but I've seen it. You can put a long screwdriver against you #4 injector and see if it is firing by comparing it's noise with the others. At that time, you can wiggle the connector on the injector as well. Quote Link to comment Share on other sites More sharing options...
misterZ Posted July 26, 2009 Author Share Posted July 26, 2009 Did that and it wasn't firing; removed connector again and cleaned thoroughly with points file and WD-40--compressed (can) air dried it and put dielectric grease on before connecting. Fired right up and purrs like a kitten (again). Sometimes it just helps to think out loud and bounce things off riverz. You can put a long screwdriver against you #4 injector and see if it is firing by comparing it's noise with the others. At that time, you can wiggle the connector on the injector as well. Quote Link to comment Share on other sites More sharing options...
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