HELP! The mechanics are stumped. My car stalls out only when, for instance, I drive and park in a lot and decide I need to scootch a bit to the side so I start back up and put the car is in reverse. It runs just fine the rest of the time, just when trying to drive in reverse when the car is warm.
Are they stumped or are they saying they cannot duplicate? Lots of these “mechanics are stumped” posts. Maybe people think that if we see a “stumped mechanic” post we will jump right on it,they should earn you more stars.
If they can’t reproduce it, then they are incompetent in addition to stumped. It isn’t that hard to put the car in reverse and leave it there for a few seconds so the car can fail. If the question, oldschool, was to get some relivant information, I fail to see what you are looking for.
Also, since this was my first visit to CarTalk, I have no clue why I’d want you to jump right on anything or the value of stars.
Many people post “stumped mechanic” posts and it turns out the “stumped” part is duplicating the condition.
Don’t you think the person that correctly answers a “stumped mechanic” question should earn more stars than they would get from a non-stumped question?
So I ask again,can the mechanic duplicate the condition? everytime or intermittently?
Still not getting the stars thing, but it doesn’t seem important to solving the problem.
Mechanic can duplicate, but didn’t find anything wrong.
OK if he can duplicate everytime he needs to figure out what is unique about selecting reverse. The first thing that comes to my mind is that the backup lights go on. He needs to check (maybe by unplugging the harness to the backup light switch) if somehow electrical power is interupted by the backup light switch.
He needs to find out if electrical power is still present at the ignition module when reverse is selected. I conclude this stalling is not related to the load placed on the engine(is it a automatic?) as you say the problem is not present in drive or a forward gear.
The stars thing is like this, Look below where it says “reverse” on the text block,do you see the outline for stars? when you like our answer you can click on these stars and they light up,sorta like giving a dog a treat for rolling over.
Your mechanics need to develop some diagnostic plans. Step one in diagnosing what’s wrong, is knowing what’s right. Unless you know what’s right, in a detailed manner, you will have difficulty in determining what’s wrong.
For your problem, when you put the gear shift into reverse, what is supposed to happen from the engine controls? To partially answer that question, the engine computer needs to know that the shift lever has been moved from the neutral position or park position. There is a circuit, to the engine computer (PCM), which tells it that. The PCM decides how much fuel, and how much additional air, to add to the engine. The PCM makes this decision from the information from sensors (like the MAF, or the MAP sensor, throttle position sensor).
Your mechanics need to check the functions of these inputs and outputs. The instructions, on how to (using a digtal multimeter), are in the repair manuals (Haynes, Chilton’s, etc.).
Your mechanics could practice the diagnostic techniques that they see (or, could see) Dr. Gregory HOUSE use (on FOX TV).