Doug McAllister/Under the Hood:
Q. I have a 1996 Lincoln Town Car with 80,000 miles. As soon as the temperature gets above 70 degrees, the car dies when waiting at a light and dies sometimes when making a turn. Or, sometimes when waiting at a light it will surge and then die.
We took it to a repair shop and had the idol valve replaced. They replaced the MAFF Sensor. (It didn’t solve it, so they put back the old one.) The last thing was to replace the ECM Module. None of these has solved the problem.
The mechanic said we should take it to the dealer and he would tell them what he has replaced. In a recent column someone had a similar problem and you suggested a fuel pressure regulator or temperature sensor.
A. It sure sounds like an IAC (idle air control) problem; this was a fairly common issue with that car. I wonder if it is a bad one or if it has not been set up properly.
A couple other possibilities may be a vacuum leak or a TPS (throttle position sensor) that is either bad or not set properly.
You did not mention whether or not the check engine light was on. If it is, a diagnostic should give the tech a clue as to where the problem lies. Sometimes a really dirty throttle valve can cause poor idle quality, so make sure that is good and clean. If it’s real dirty consider having a fuel injector service and an upper intake cleaning as well. These cars do not tend to have fuel injector issues like the one I wrote about in a previous column.
Q. I am lost about how to continue. I have a 2006 Chrysler PT Cruiser with 37,000 miles. The entire instrument cluster will momentarily light up, the gas gauge will bounce and sometimes the car will lose power. After a few minutes power returns and the lights return to normal.
Two different dealers have replaced the instrument display and inspected the wiring harnesses. The turn signal stalk has been replaced. I replaced the battery in case there was an intermittent short there, and visually inspected the battery cables.
Each visit, the dealer will keep the car for multiple days, never see the problem and then return the car.
Chrysler will do nothing since they have not seen any problem like this. I am highly concerned since losing power steering, brakes, or other unexpected loss in power can result in an accident, especially in highway conditions. This exact same situation is shown on a blog from a few other drivers.
What should I do? This is a lemon problem, brought to Chrysler during the warranty period, that they have been unable to fix.
A. It sounds like you have a challenge on your hands. There is nothing worse than a car you don’t have confidence in. I’ve done some investigating and, unfortunately, I don’t have an answer for you. It seems from your description that you may have two different problems, unless I am not understanding correctly.
You say that sometimes the car loses power. What does this mean? Does the car hesitate, won’t accelerate or does it almost die? Does it happen at speed or when accelerating from a stop. A better description here would help. Also, how often and can the loss of power occur without the dash issue occurring or are they always related?
These intermittent problems are frustrating for everyone involved. Chrysler did have a fair amount of instrument cluster issues but since replacing it didn’t fix the problem, I doubt if that’s it.
I found a couple of similar complaints where an ignition switch solved the problem but, unless you could catch it in the act, it would be a guess. Unless you are willing to pay an independent diagnostic technician to track down the problem, you will have to continue working with Chrysler until they resolve the problem for you. Please let me know what eventually fixes the car and good luck to you!
Ÿ Douglas Automotive is at 312 S. Hager Ave., Barrington, (847) 381-0454, and 7218B Virginia Road, Crystal Lake, (815) 356-0440. For information, visit douglasautomotive.com. Send questions to underthehood@dailyherald.com.