My jimmy seems to be missing, but only when it rains, I would like some help. Mary

Answered that already

if your vehicle has a distributor cap on it, this is where i would check for a cracked cap, this will allow moisture to get into, normally when it rains.

Try changing the spark plug wires. With age they tend to build up too much resistance & the spark at the plugs become weak. If the spark plugs haven't been changed, have this done because with every 1000 miles the gap widens 1/ thousandth of an inch altering engine timing & preformance. Old spark plugs make for bad starting. As far as the leak, do you have any rusting around the front window frame. If yes, have it repaired by removing the window & accessing the damage. Often the window seal is worn with age & the like. You could have someone with a garden hose pour water on the car til the leak is recognised by looking under the dash. It may also be coming from a rusted floor board. Check under the Jimmy to see if there are any holes obvious. Hope this helps. Good luck!

Please help us. I have the same problem with my 99 Jimmy. I was driving on the highway going 70 and then it started missing. Changed all the plugs, wires, rotor and cap but to no avail. HeLP! please email me if you have a solution to this problem. ([email protected]) thanks a bunch.

How old is the cap? Could the new one be bad? Also when it won't start do you see any sparks jumping from the coil or wires?

What you can do is put water in a spray bottle and spray the plug wires and coil down and see if it will act up.Hope this helps.Good luck.

If you have a wet seat then it is likely defective weather stripping around the window.

Try this. If the floor is dry, then it rains and the floor remains dry, only gets wet after a drive in the rain or on wet streets, you may have a hole somewhere.

Check for holes from missing rubber grommets or holes in the floorboard or firewall from rust. Check for any rust holes or missing rubber grommets under the car or on the firewall, anywhere water can splash up into the vehicle from driving in rain or running through puddles..

Check wet spots along the carpeting all the way up under the dash, if the wet spot is higher than the floor itself, you could be getting the water from splashing through puddles.

Any holes under the car or in the fenderwell even up on the firewall can cause this problem.

First check for any obvious signs of rust, if none are found then look for missing or defective rubber grommets.

It sounds like you need a tune up, Spark plugs and wire and cap and rotor, fuel filter and clean the EGR Valve. I'ld say the EGR valve is dirty with carbon which is common in the 95 JIMMY"S and BLAZER"S which also means the throttle body needs to be sprayed down with throttle body cleaner, not carb cleaner since it's to corrosive to the gasket on the throttle body. Keep me posted, be glad to answer any questions you may have and good luck friend. 

HAVE YOU HAD YOU THROTTLE BODY AND OR YOUR CAM SHAFT SENSOR CHECKED OR YOUR AIR TEMP SENSOR ? IT MOST LIKELY SOUNDS LIKE YOUR AIR TEMP SENSOR IS'NT LETTING ENOUGH AIR IN OR OPENING YOUR MASS AIR FLAP ENOUGH WHEN ITS COLD OUT CAUSING THIS.