Buy Now | Log In | ALLDATA Corporate Site |
Back To Home Page
Log In To Your Subscription
Go To ALLDATA Back Home
Buy A Subscription! Back Home About ALLDATA Information View Sample Vehicles Read Testimonials View Factory Service Bulletins and Recall Titles Contact Us
Dowload Our Navigation Chart
February 2015: New vehicles added including 2014 GM.
• View New Vehicles
October 2014: Release of 2013 along with initial 2014 Vehicles
• View Vehicles
View All News and Updates:
• Go To News
Tech Tips
  Read All Tech Tips

ALLDATA Tech Articles Are Updated Weekly
• View All Tech Articles

  Dodge Durango: Brake Pulsation Problems In Paul's Durango
• Read Dodge Article
Fixing A Smelly Audi Audi Tech Tip: A4 begins to Smell caused by a Faulty Hose Composition
• Read Audi Article
Why Do You Need To Change Your Timing Belt? Why Replace Your Timing Belt
• Read Belt Article
Jim Grant Tech Tips Jim Grant Tech Tips
A collection of helpful articles based on reader submissions
Home >> Featured Tech Articles >> Go Back
  Jim Grant's Tech TipsJim Grant's Tech Tips
Below is a collection of Jim Grant's Tech Tips sorted by Vehicle Make. These Tech Tips were answers to questions submitted to Jim by users over the course of many years.
If you have any questions, please feel free to email us.



Lincoln - Mercury
  Jim Grant's Tech Tips

93 Dodge Grand Caravan, Transmission or Engine Problems?
Q: I have a '93 Dodge Grand Caravan, with a 3.3 liter engine and automatic transmission. It presently has approximately 150,000 miles on it. For about a year now, sometimes for a couple of months at a time, and definitely not all the time, it will run very rough. It won't shift into second gear when it should, it will "clunk" when down shifting, it will surge or feel like it isn't getting enough gas when you're cruising. It almost feels like water in the gas, that type of rough running. But... not all the time. Sometimes just for a couple of days at a time. You can drive six miles without a problem, shut off the car, restart it, then it will be awful. A transmission shop has looked at it and says the computer does not show any malfunction. Our regular mechanic can find nothing, mostly because it never acts up when trying to diagnose the problem. Gas, weather or any other variable doesn't seem to matter. It has only stalled twice when running rough, otherwise we just go ahead and drive it! It almost seems to me that if you start the car and it happens to be at the wrong time in a cycle, it acts up. What about an oxygen sensor? I would certainly appreciate your help..... Sara

A: Your vehicle has a computer for the transmission and another computer for the engine. When your technician was checking the engine did he/she check the engine's computer, for any diagnostic trouble codes? An automatic transmission will not operate correctly if there are engine problems. Make that a computerized transmission, and the problems are compounded. The engine has to be running correctly before the transmission can. You said, " It almost seems to me that if you start the car it happens to be at the time in the cycle, it acts up ". Have you tried shutting the engine off for a short time and restarting it when this happens? There are sensors that tell the engine computer where No. 1 cylinder is and how fast the engine is turning. If this information gets jumbled-up the engine will run erratically. The transmission computer shares the same information, it too becomes lost in knowing what to do as well. A problem with this sensor is caused by engine oil leaking into the electrical connector. The engine oil interferes with the electrical signal, confusing the computer, which isn't smart enough to realize it's being confused. A closer inspection of the sensors that make the engine run may provide an answer to your problem.

Have any Questions About Please Email Us
Buy Now | Log In | About | Sample Vehicles | Testimonials | Join Affiliate Program