ShiroiHikari (post: 1250185) wrote:So our minivan has been running rough, hesitating, being sluggish, and stalling on us. So far, it has only cut out when I've just slowed down from driving and am about to park in a parking space, which is really weird. Also, it always starts right back up. What the heck is going on here? I've heard that ethanol can make some cars do similar things, but I also heard that it could be spark plugs or the fuel filter. Bleh! Does anyone have any ideas?
Paul's top picks:
Fuel: If it is fuel injected, there will be a valve on the fuel line leading to the injectors on top of the engine. It will look alot like a valve from a bicycle. What you do is, after appropriately adorning basic self safety clothing like goggles, gloves and clothes you don't care to get ruined, is remove the cap and view where you think fuel will spray from the valve. Have someone sit in the drivers compartment to turn the key, Take a tin coffee can or a glass jar and hold over the valve about 6 to 8 inches will work, and while the driver cranks the engine over a couple of turns, press the valve button down with a screwdriver, much like you would letting air out of a tire. The idea is to see how strong fuel is released. A good strong squirt, like from a powerful water gun, is an indicator that fuel is not the problem. Remember, the can is a catch zone to control the fuel's direction and intensity (A safety net and if the fuel doesn't reach the catch can or jar.). If it dribbles out or just flows out, doesn't reach the catch can, there's something going on you fuel system contributing to your problem.
Spark: One at a time, remove a convienent spark plug from the engine and reattach the wire to the plug. Lay the plug next to something metallic, like the engine, and have your person turn over the engine. What you are looking for is a spark. It should be strong and consistant. (Don't touch it while the car is being cranked or running, it will shock you and it hurts.) If you have a good spark then everything is good as far as getting a spark. But then you have to look at the spark plug and if it is in good condition. You may have to do this with each spark plug. If one or two look bad, corroded or broken, it's time to replace your plugs and wires. If you are not getting a good spark, or intermittened with no clear consistancies, then it may be your ECM (Electronic Control Module). The electronic control module replaces the old style distributor. It basically is the all important master spark zone to which feeds all the spark plugs. Following all the plug wires back to a central point is a cap. Under that cap you will find the ecm.
From what you described so far, I don't think it's either one. If it's a newer car with Fuel Injection, my next step would be to check temp guages, oxygen sensors, and throttle position sensor. If it's carbureted, then you may have clogged jets in your carb, which means taking it to a shop.
On the fuel injected vehicles with computers, a faulty temperature guage, faulty oxygen sensors, and other emission sensors can give the computer a false reading and send the wrong information to the fuel injectors and throttle position sensor and could be the reason why the vehicle will start fine but run crappy in gear. I had this happen to me on a Ford Taurus I worked on. Changing oxygen sensors solved this issue. On a Saturn L200 a faulty Throttle position sensor was the culprit.
Now there is one more thing I think you should check. That is the exhaust. While the vehicle is running, wrap a 33 or 40 gallon trashbag around the exhaust and start it up. (Don't forget gloves to protect your hands from the heat, although if you start the vehicle cold you shouldn't have the problem). How fast does the exhaust fill up the bag? If it's fast, your exhaust system is clear and working fine. If it's sluggish or slow, then you may have a clogged exhaust system. Depending on how many miles put on the vehicle, it could very well be the catalytic converter.
From here, you will need to take it to the shop, because if none of these fixes the problem, it's beyond the help of home mechanical repair. At least that is what I would do next. Let me know how it turns out. If you can let me know the make and model of the van, engine size, year, Carb or Fuel injection, it would help alot. I can use that data to help search down a trouble-shooting guide to narrow the problem.
Now let's pray. Lord, my CAA friend's van is very very sick, and it needs help. Your help. Guide us, direct us, show how we can fix this vehicle, and get your child back on the road. Your word tells us to call on you, and we are, and that you will give us peace. It's in your hands, now guide us. Heal her vehicle. Thank you Lord, in Jesus name. Amen.
Paul