93 Camry Engine Cutting Out (5-speed)

Weird problem, just want someone elses opinion. In any gear, at any rpm range (randomly), and at any throttle position the engine cuts in and out and makes the car buck. When its in neutral it will rev right up to redline with no hesitations or cutting in/out, it also idles fine...so it only does this when it's under a load. Spark plugs and wires were replaced in the last 6 months...theres 133k on the vehicle...no check engine light on.

My first thought was fuel delivery, but it doesn't do it in neutral so that wouldn't make much sense. Spark is more than likely good b/c plugs/wires are basically new. My next thought was maybe the timing belt jumped a tooth, but it does sometimes get through the rpm range in a gear with no problems, and all the power is there and theres no engine noise (tapping/knock). Electrical would be my next thought, but all the lights/dash lights stay on (no flickering) when it does this.

Now the downpipe is coming loose, and that would obviously effect the O2 sensors input/output...question is, would the ECU detect that and cut fuel or something? I wouldn't think so being that it's only a 93, but is it capable of doing so? Or could it be seeing too much O2, and dumping more fuel in and "flooding" the spark (forgot the proper name).

These thoughts are just coming to me as i'm typing sorry if its out of order or anything, any help is greatly appreciated.

ps- anyone make a datalogger for these cars?

Missing under load is usually caused by an ignition system problem. You say the plugs and wires are 6 months old. What about the coil, distributor cap and distributor rotor? My gut feeling based on experience says check the coil. You can use the sticky at the top of this forum for the specs. You will need a DVM.

Mike

Yeah those are probably the original distributor/cap/rotor in there...i'll have to check them when I get out of work tonight..i'll update then thanks.

It definitly sounds like an ignition problem. Were the replacement sparkplugs oem equivalents? I ask this because we run across this all the time with hondas that have had bosch platinums put in them. The coil does not have the voltage required to fire them under load.

The problem would not be caused by a timing belt that jumped a tooth. When that happens the car favors one end of the RPM range depending which way it is off. I have never seen this to cause the engine to cut out.

The fuel control on your car cannot trim the fuel enough to cause a lean enough condition for the engine to cut out. So, no it would not be your exhaust comeing apart.

Fuel could still be an issue because when you are reving the car in neutral you cannot get into the throttle for extended periods of time like you would under load. I would still guess that ignition is the problem.

Well thanks for the suggestions, I forgot my DVOM at work so it'll have to wait 'till tomarrow to test it out. I can't remember if I put NGK's or Bosch's in there. The more you talked about it the more it made sense to be an ignition problem...I wouldn't think it would be the plugs though because they wouldn't all die out at the same time, there would just be misfire's here and there...so i'm leaning towards distributor/cap/rotor.