Question Mr. Joy,
I have E-Mailed earlier about a probem that I am having. and you said that you needed more informaton. I am going to start over, maybe this will help.
I have a 1995 olds Aurora. It has a cadillac engine. There is a display on the dash of this car that is a information center. It gives the Average miles per. gallon, Date, gallons used, engine information, next service, miles to destination and so on. I keep it on the average miles per gallon.
About 36,000 miles ago, the transmition started giving problems. It would not change gears. When you excellerate and take you foot off of the gas pedal it would go to idle. The engine rpms would not remain, as normal driving. It would coast, like being pushed and then let go. I was told that this car goes into a limp mode. And that was what it was doing at this time. The transmition was going to have to be replaced. This was done. I bought a factory rebuilt transmition from them and they installed it. Until now everything has been doing fine. But now, when you are driving it does fine until the engine gets warm. Then it will not change gears again. Before it would not change gears even when cold. Now it seems to be effected by temp. It does not do this all of the time. And this makes it hard to put you finger on, and for as trouble shooting. While traveling to work today, it started giving problems again. I carried it back to the dealer again, and told him that the problem was affected by temp. And that if he checked it at that time he could see what I was talking about. He waited until it sat for a while before checking and it started working normal again. I told him that if he waited it would not show trouble. He said that he had to wait until a mechanic could look at it. He said he would drive it at lunch, and see if it would do it then. It did not. And he said that another guy drove it for a while and it did not give any problems. He said that there were not anything that he could do until it acted up. and there mechanic worked off commition, and that if he was not pulling wrenches, he was not making money. I understand that, and also know that it is hard to trouble shoot something that is not acting up at the time. But at this point I cannot trust the car. You never know when this is going to happen. When the transmition does not shift. The average miles per. gallon display shows like this -- -- -- instead of numbers, and flashes. The temp. will not work at this time either. After it sits for a while, the display start working normal, the engine temp. starts reading again, and it starts shifting gears again. One other thing that it does when acting up. The transmition bumps real hard when changing gears from park to drive, and from park to reverse.
I wrote earlier about other problems. The engine was shutting down at times. The service manager said that was due to the EGR valve being deffective.
One other thing was the gas pedal would make bumping noises when the engine was switched off. He said that due to the Idle Speed Control Motor was bad. Does this sound right?
Thanks for writing back in such a timely manner.
I look forward to hearing from you again. Thanks!
Larry Conger Sr.
AnswerVERY VERY good detailed information. I appreciate it and now we can get to hopefully find your problem. Usually when someone asks a question all the information I get is: MY CAR WON'T START. WHY ?. What do they think I can do with NO other information ?.
OK, Intermittent faults are sometimes VERY illusive and can be quite diffict to diagnose. On many occassions, Whenever I have a customers vehicle doing what yours is doing, I would talk to the owner personally and we would take the vehicle on a test drive to see if the problem occurs. If it did NOT, I would ask for WRITTEN permission to drive the vehicle over the weekend or for a few days during the week. In ALL cases the fault would occur and IF the technician knows what he/she is DOING your problem can be diagnsoed by simply understanding what the vehicle is doing at the time of the fault.
There IS a RISK in that you must have TOTAL FAITH in the technician's ability to safely operate your vehicle.
WITHOUT actually driving the vehicle personally, But from many years of experience, I would have to say that your problem is either a intermittent SOLENOID failure, An intermittent CONTROL BOARD failure, An intermittent wiring fault within or at the transmission.
Just because the transmission is NEW or REBUILT, Does NOT guarantee that it is exempt from having a faulty component(s). I have seen MANY brand new transmissions, Engines and various other components that were faulty right out of the box. To which I have learned to ALWAYS test each component when it is COLD and then I would heat up the component using a hand held hair dryer until the component got to what was fairly close to normal operating temperature as if it was on the vehicle.
This hair dryer method has been very successful and I still use it today although I am semi-retired and am teaching my son how to PROPERLY diagnose a vehicles problem and make professional repairs and repair the vehcile as if it were my own.
This hair dryer method has been very effective in diagnosing TEMPERATURE SENSITIVE components of which you are experiencing. If I had the thought that the vehicles computer was the probable fault, I would heat it up using the hair dryer and if my hunch was correct the computer would emit the intermittent fault and a simple computer replacement was the resolution. This method also works very well with transmission components as said above, I would simply heat up the suspect component and test it manually and in 90% of all cases the fault would occur and a simple replacement was the resolution.
I also worked on COMMISSION, But IF you are GOOD enough and have the technical expertise in knowing what you are doing, There is NOTHING that cannot be found and fixed.
I managed to make $80,000 working strictly COMMISSION my last year prior to retirement.
Unfortunately, Today's technicians, Do NOT want to make any effort to obtain, Or attend the manufacturer's school's that are available for FREE each and every year to learn about the new electronic changes for the current year vehicles and or take the time to make an effort to properly diagnose and test the suspect components per the methods that I previously stated above. I see this problem getting WORSE every year and I have been taking ON some of these CAN'T BE FIXED problems with numerous facilities in my area and guiding my son, He makes himself quite a few extra dollars that makes his car payment every month.
I apologize for being so long winded, but it burns my BUTT when I get these types of EXCUSES from dealerships service departments, Who in my opinion just don't give a DAMN whether they fix your problem or NOT.
The only suggestion, Other than bringing the vehicle out to my facility, is to find another dealer who has some PRIDE and EXPERTISE in their service department.
OK, My suspected intermittent component failures where I would do my testing would be at:
The vehicles computer.
The wiring to the transmission connector.
The internal transmission electrical components.
As far as the display, In most cases this is a fault within the vehicles computer as I have seen very few faulty display units over the years, But it IS possible, Thus the hair dryer method is used.
Other than the transmission change what other mechanical work has been performed on this vehicle ?.
Almost forgot about the bouncing gas pedal. This is usually caused by a faulty IDLE SPEED CONTROL MOTOR and or an intermittent faulty THROTTLE POSITIONING SENSOR that in some cases does NOT illuminate the CHECK ENGINE light. Thus the TPS would be HAND TESTED and the hair dryer method employed.
I wish I could give you an EXACT component that is causing your problem, But without performing the above test methods, I would only be GUESSING.
let me know what you find out.
autohelp
