Struggling with a stumble at idle and getting any power as revs increase
Sorry that I don't have an answer as I am also in Camry Hell. The radiator cracked and let the steam out, the car got hot. never seized and would always turn over on the starter. Compression is 200-205 in 3 cylinders, 170-175 in #2. It runs but stumbles badly when under load, although it seems to rev freely. I have replaced both O2 sensors, the water temperature sensor up by the head, the fuel filter, the air filter, the radiator, removed the idle control switch, while cleaning the throttle body, put that back on once cleaned. Also checked the DC voltage at the throttle sensor, which gave smoothly graduating readings from .9 up through about 3.55 and back. I've pulled and reset the 15amp fuse for the EFI a number of times... it runs better but still stumbles badly. No water in the oil, and no metal in the oil. I'm running out of ideas and am hoping it isn't the brains for the EFI. Any ideas? I'm just about out of them at this point. Thanks, CamryHell (PS, it's a 1994 2.2 liter 4 cylinder Camry w the automatic trans.
PS: It has 209K miles, I am the original owner. It does not burn oil. I checked all 4 plug wires first with the timing light to see that they were firing, then pulled them and set them on the exhaust shield to physically see that they all fired as the motor was turning over. My compression test was done repeatedly with no spark plugs in any of the cylinders (spinning free). The ignition timing is in the ballpark, maybe off by a degree, never been a problem in the past. The exhaust is not plugged you can feel the pulses coming out the exhaust in back. Thanks, thought I'd provide all the info I could.
Any warning light on when the engine is running? Have you checked for any stored codes. Have you checked the EGR valve to make sure it is not stuck in the open position. The Egr modulator has a filter under it's cap. If that filter is restricted...EGR will come on prematurely.
For a few minutes and only once a week ago, I got it to flash 25 and 26, over and over. That went away within a few minutes, but might give a clue. It is not OBDII like the 1994 V6 engine Camry, so it's pretty sketchy on the codes, being the flashing OBD1 kind. And as I mentioned, it was only for a short time that it flashed any kind of OBD1 code at all, no longer the case. Thanks.
I had not checked the EGR valve, not sure exactly how that would be done.... but I will dig around for tutorials. Thanks
Good....check the rubber hoses carefully for brittleness and cracks. Also...I believe this engine has a "Fuel Filter" in the intake manifold that feeds Vacuum to the MAP Sensor It's really just a fitting with a screen in it. That Vac, . hose gets mushy and collapses easily when the engine is running.
I was looking at that line, it's got a strange plastic wrap around it and goes from the MAP sensor to the back of the intake manifold with some sort of small fitting at the manifold. I will disassemble and clean that area today as well. Thanks.
Well, removed and cleaned that fitting on the back of the EFI plenum, also removed and cleaned the EGR and PCV valves, all much cleaner and the engine runs much smoother... BUT it still hasn't enough power to get it up the driveway, or enough to dare driving it anywhere. Is the MAP sensor something that could do this? I'm hearing the steam bath and extreme heat that the engine was subjected to could have kiiled the cap/rotor although the plugs seem to spark well enough on observation. ?
Suggest a reflash for trouble codes. My guess is the engine is running lean. Without the aid of a scan tool we would start checking sensors with a digital volt meter. We would also check the fuel delivery system with a fuel pressure gauge. To rule out that EGR....you might consider disconnect and plug the vac line...thus...disabling same temporarily. A bad MAP usually causes a rich running condition. Try disconnecting the electrical connector answer see if she runs any better.
No trouble codes although a couple of weeks ago for about 10 minutes it was flashing 25 & 26 when checked. The problem turned out to be the coil and sparkplug wires which must have gotten cooked in the steam bath. Previous to that, I took off and cleaned/verified operational the EGR and PCV valves, and replaced the O2 sensors (2) and the water temp sensor and fuel fliter/air filter. It should run for a long time after all that. Thanks
HooRa....nice job. Thanks for the update. Lessons learned. We should have performed the "Water Spray Test". This is where we use a spray bottle with water in it and with the engine running...we start spraying the ignition system with H2O. Engine with bad wires ...stalls out. OK...Good luck and thanks for sharing.
Great tip for if this issue ever shows up again. Thanks
