Hi,
I'm again posting the same problem but from a new perspective, I hope someone can help me figure out the best course of action.
Bought a used Camry 2000 4 cyl from a dealer at 93K, vehicle was running superbly - ofcourse paid a much higher price.
After about 200mi of Highway driving, I noticed that on stopping (like at a red light), the engine was going down on RPM and rising up again. It was enough to cause engine jerk a little and I could feel it. Took it to the dealer who performed diagnostics and said that this was normal.
A few days and the problem became worse, after driving for a while I could feel th jerks. Check engine light came up but went off before I could take it to a Toyota dealer. They performed some diagnosis and told me that one of the ignition coils were aftermarket hence bad. They offered to change it for $400. Upon enquiring further they suggested that the reason they believe it to faulty is that "its aftermarket". Upon my declining they started offering me other services like transmission flush and what not, a total bill for $1500. Anyways I wasnt too sure, so told them to not do anything. Paid 120$.
Next I took it to a corner mechanic shop who changed the spark plugs and repaired the "ignition coil ground wiring" -- not sure what that is. Car ran ok for about a couple of months and couple of thousand miles. But soon problem came back. Infact on a short trip, it almost seemed like it would stall. Check engine light came up.
Having seen both, the dealer and the corner mechanic, took it to Meineke this time. They read the code of P030 (misfiring in all 4 cyls) and said that firstly they will replace the spark plugs and wires and clean injectors and if still problem persists, they will have to replace the ECM. Well, I let them change the wires, the plugs and Fuel Injection cleaning - $550 job, I can't *feel* the RPM variation but I can *see* that on the tachy - same as before.
My reading through the manuals and groups and looking under the hood it looks to me that the wires that go into one of the ignition coils ( the low voltage side) may have a loose connection, although I did not find anyway to verify that. I also see that the plug sort of connector to one of the coils is different in color than the original. One of the wires coming out of that cap has a winding connection to another wire about a inch ahead and covered with tape. I also see that some wires from that cap go to the ECM and some to the remote starter module. I tried reading through repair manuals, forums etc. but no one talks about these wires - I dont know if it is a possible problem and can be missed by mechanics?
I'm fed up of this problem and scared to even use the car to avoid this ordeal over and over again - everytime it shakes a bit - it seems to mock me for failing in a careful investment. What is the best course of action I can take? Can it be fixed? Or should I just get rid of it "as is" vs fixing it and then getting rid of it.