Hello fellow Camry lovers

jrw9553

Hello group. I have a very complex issue that I hope to get some impute on.
96 Camry, 183,000 miles. I have an independent mechanic that has worked for an import place for 30 years. Even he is stumped.
Symptoms; Stalls at idle, occasionally. Never stalled while in motion. Sometimes after stall, it will start right back up and go. Rarely, it will take several cranks to restart. Occasionally at idle, engine speed will surge to about 2000-2200 rpm. Normally idles at 800. Sometimes after pressing accelerator after a stop light, the pedal seems sluggish. It seems to want to stall. Almost stiff feeling. I tap it quickly and it takes off normally.
Sometimes, I can drive the car without issue for a week or 2. Then it reappears. The first time I had an issue 3 months ago when my car would not start after a visit to McDonald's. I came back an hour later, it started up.
So there is an idle surge, and stalling at red lights. However it is very sporadic and unpredictable. No real pattern to it at all. I can also feel slight misses at cruising speeds. Very subtle but I notice them.
Parts that have been replaced thusfar. I think this is called wasting money. Alternator, EFI relay, cap and rotor. here is the clincher,,, idle speed control valve. After that was replaced, the engine light never came on again. It had been on for the last 2 years. But never produced a code on the reader. My mechanic tried to drive the car with the code reader affixed but could not pull a code up. He says because the car restarted immediately. He was hoping that it would start hard and spit out a code. No such luck.
He has ideas but none make sense. These things just go bad and would not be so sporadic. Fuel pump, Fuel filter, MAP or MAV sensor. He tried to test the fuel pump relay but did not have the means. He is confused about if the car even has a fuel pump relay OR a main relay (as he called it). The main relay supposedly being located in the same compartment as the EFI relay, he thought. The fuel pump relay being located under the glove box.
He thinks that the idle air control valve may have faulted as soon as it was replaced because it may have been the wrong one of was faulty? I got a brand new one with gasket. When I was looking for that part, many of them looked identical. But he thinks they are actually different because of some reason which I forget. He is almost leaning towards another one of those. Keep in mind that this is a trusted friend. He is charging me next to nothing to do parts and figure this out. He is not the problem.

So any thoughts would be appreciated. If you have any questions, I will reply. Thank you very much for your time.
Jim

carboy21

20 year old Camry is dying of old age. Just dump it.

thecardoc3

What you are asking for, and that is someone to just tell you what is wrong isn't going to work. Someone will have to approach this with the right tools and routine and prove what is going on. The first thing that they have to do is prove whether you are losing spark, fuel, both, or if the engine is stalling for another reason. Once that first question is answered, then the focus shifts to proving why. You are going to need a electronics/diagnostics specialist. It takes a very patient approach to solve problems like this because the only tome progress can be made is during the stalling event, and it may take several of them to start to narrow down the area of concern.

Mr_Shiftright

Or to put it another way--this is one of those rare cases where you hope the problem gets worse, so that you can catch it.

jrw9553

I understand there is no magic answer. I posted just to see if anybody had experienced these symptoms before and found the problem. My guy has it narrowed down. He says it has to be the idle motor as he calls it. (Idle air control valve). he says it is common to replace these and have it go bad or not agree with the computer. They replace it with another new one and it works fine. That might be the next step.

thecardoc3

jrw9553 said:

I understand there is no magic answer. I posted just to see if anybody had experienced these symptoms before and found the problem.

That's the perspective that is the problem. I have found EGR issues, igniter issues, (the ignition module ), wiring issues, as well as the IAC, and even the PCM. Without truly testing correctly, nothing is ruled out and that's why it has degraded into a blame a part game.

jrw9553 said:

My guy has it narrowed down. He says it has to be the idle motor as he calls it. (Idle air control valve). he says it is common to replace these and have it go bad or not agree with the computer.

Based on what, experience? Even if he actually is right (doubt it) this is something that can be proven if it is in fact the source of the issue. The reliance on seat of the pants experience, without backing that up by taking full advantage of the tools and training that are available to techs today is one of the things that is contributing to the shortage of qualified techs in the trade.

jrw9553 said:

They replace it with another new one and it works fine. That might be the next step.

If they replace it and it does fix the car without testing and proving why, then they won't know "why" it worked. That means nothing was learned from the event and the actual lesson that it should be teaching will be delayed until some other day in the future, if ever. That also means that gap in their knowledge and experience will reveal itself in other places as well until they finally make the effort to do something about it. The difference here is that a more qualified technician would have dealt with this the first time. You would have never seen the need for the second, third, or how many revisits and the ability to do that goes largely invisible to most consumers. I told you how it should have been approached on the first visit, it should be approached that same way this time too.

jrw9553

OK Cardoc
Some of your comments makes me think I am lying on a couch in a shrinks office.
Tell me if you agree with this. The best approach is to make an appointment at the Toyota dealer and have them take a crack at it. I only want the diagnosis, I will have my guy do the work at about 1/10 of the dealer cost. I just hope it doesn't cost me $300 for this service. I will print out the symptoms in detail and list replaced parts. Also wait on site for any other possible questions. Does that sound like a reasonable approach?
Thank you for your help, Jim

thecardoc3

I can't speak for the dealer if they will be agreeable to that or not. Consider that having them only do the diagnostics doesn't reward the investment that the tech has made to be able to do work at this level. Plus you have a random failure, and it's already a moving target because someone else has touched it first.

This could be a relatively simple diagnostic, and it could be very labor intensive. There is no way to know until someone starts investing real time towards it. The list of previous repairs is irrelevant to the next technician to investigate this, in fact that information is something that the tech has to "forget" while performing any testing. Previous repair information could lead to falsely blaming a given part based only on suspicion, like your other guy questioning the IAC is doing .

The tech needs the symptom details especially things like how long the car needs to be driven in order for it to act up. They need to know if rain or any other weather conditions have an impact.

carboy21

20 year old car will always have failures coming up. My Toyota dealer does not even bother to see 15 or more year old cars. They claim they don't carry parts

jrw9553

Hello cardoc3
I finally did leave my car at the dealer for 2 entire days. It never failed on them after several start ups and drives and idle time. Figures. They checked out a lot of things along the way. Their best and only guess was adding fuel injector cleaner, which they did. Some stuff on steroids. Hope this works. I will be adding some Lucas FI cleaner for 2 more fill ups at least and see what happens or does not happen.
Total cost for several hours of attention,,, $0.00. I was impressed.

thecardoc3

Don't be. That means the employee, AKA technician assigned to the car wasn't paid for the time that he/she invested. The tech did do the right thing by not guessing and taking a patient approach while trying to get the car to present the symptom, but the rewards for doing that leads to disenchanted ex-technicians when they aren't paid for their time.

jrw9553

Hello Cardoc3,
In this entire correspondence you never addressed the question about a car. You seem to be more concerned with your own vanity. You have no interest in helping people but only an interest in yourself. Your help was non existent. Your self absorption was a useless waste of time.

carboy21

Toyotas are known to suffer from oil sludge. Add a bottle of Seafoam to the fuel and also one bottle to the engine oil filler .
See if it makes any difference.

thecardoc3

jrw9553 said:

Hello Cardoc3,
In this entire correspondence you never addressed the question about a car. You seem to be more concerned with your own vanity. You have no interest in helping people but only an interest in yourself. Your help was non existent. Your self absorption was a useless waste of time.

Do you feel better now? You couldn't be more wrong, and its unfortunate that you can't see the big picture. So you think that stopping the OP from wasting money replacing parts that weren't confirmed to be defective didn't help him. OK, got it.

Nobody can just tell the OP what is wrong with this car, or just about any other without testing and proving what is going on. FWIW, I have done more to explain how to take a disciplined, repeatable approach towards problems like this one than you will ever know.

The reason that the OP's mechanic has failed to diagnose this is outlined by the responses. Techs get to choose to learn how to tackle problems like this one, or make good money doing easier work. Like most, he chose the latter and that leaves his abilities outclassed by some kinds of problems. IMO. Consumers at large need to know more about what it really is like to be a technician and especially one that addresses these kinds of problems.