My trusty 1995 Corolla with 240K won't start. It sounds like its gonna start on the very first start with no previous starts, after its been sitting for a few hours but doesn't. After the next 2 or 3 tries, it sounds hopeless.
I've tried to do some limited troubleshooting, here is what I have done.
I checked my timing belt by turning the engine over and observed distributor rotor rotation
I swapped distributors with one from my wife's Corolla 94 that does start and run
I took my 95 distributor and put it in my wife's Corolla 94 and it does run my wife's Corolla 94 , she is even driving the Corolla with it now.
The 95 won't start with the Corolla 95 or 94 distributor
I see spark at all four plugs when I hold the threads to ground
I swapped rotor and cap and plug wires and plugs from my Corolla, no luck
I have no ECU OBD1 codes (Is it the T-E1 jumper?)
I disconnected various sensors to see if my ECU OBDI flashed the right codes and it did
I hooked up a Noid light and checked all four injector circuits and they all flash
I checked engine compression and it was 150 psi all four cylinders
I see wet fuel on my plugs when the engine cranks (does not start of course) and I the pull the plugs
I observe fuel coming out of the rail when I disconnect the supply line
I had a goofy theory I had a clogged return line so I tried to start the car with the fuel rail return line flowing into a plastic bottle, I got gas in the bottle but no start
I tested my fuel pressure and I got 32 Psi. Is that too low?
Do I need a new fuel filter?
Can anyone please help. I am at my wits end,
Sleepless/Witless in Seattle
Do you have air? Not to be a smartass, I just thought that if your Idle Air Control (IAC) valve is not opening correctly, then you pretty much immediately flood the engine. Did you try starting it with a little throttle? On the first try that is, after it has been sitting for a while. Or after you dry the plugs. The IAC valve can get stuck because of the oily residue that comes from PCV and EGR venting into the throttle body.
Fuel filter's worth a try. I doubt that's your problem, but if it hasn't been done in awhile give it a shot. It really sounds to me as if the car has been flooded, which indicates to me no spark. Another vote for the ECU. Try disconnecting the neg terminal on the battery for awhile if you haven't already. That's about the extent of my electrical knowledge.
Have you checked/cleaned the mass airflow sensor (or swap with the other car) to try? MAP sensor could also do it AS WELL AS the temperature sensor for the ECU. Off the thermostat there are 2 sensors, one for the fan and one for ECU. I think the lower one is for ECU iirc. If it does not read correctly the car will throw the mixture totally out as it thinks it's a lot colder than it is.
When mine went the car was starting hard and would barely idle (you had to hold/pump the throttle to get it to go. After 1 minute car ran perfect but next morning it went right back to same issue.
As stated, dry the plugs and replace, push and hold pedal so throttle body is wide open and crank it. If it starts you might need to play with throttle to keep it running. That sensor won't throw any trouble codes as it is "working" but it is not at correct temperature/resistance reading. There is a test procedure with ohm readings based on freezing the sensor and checking it in the shop manual. Sensor was pretty cheap and a 5 minute job to replace. 1 wrench, teflon tape, 1 plug.
Sorry my manuals are gone but maybe somebody else that has one can confirm location.
Might just try disconnecting that sensor wire first and see what happens. Check engine light should be on but it might set it at a default mixture accordingly. If it starts, plug it back in and see if it stalls.
Sorry forgot about that. It DOES have though the ACT (air charge temp) in the air box and and MAP sensor on the passengers firewall. Any whacky readings on those would contribute. My guess based on the flooding out/wet plugs is still the coolant temp sensor.
If that doesn't work here's my other thoughts.
Sig says Seattle but does yours also have California Emissions with the EGR valve? Valve could be sticking/clogged
Obviously you checked for the spark but is it at the correct firing time? When you swapped distributers are you maybe 180 degrees out of time? Timing belt jump a tooth or more?
THANKS everyone
I thought my distributor was off 180 also--turns out it goes in only 1 way
I wil cehck the coolant temp sensor--its right below the distributor, might have knoked it off
Can a sticking IACV prevent car from starting ?
When I changed the filter, fuel flow was very low for a while as the filter got filled and it almost started running, boy was I excited. Sounded a bit throaty, looked for some kind of exhaust interface in the intake like an EGR did not see one.
Yes, a sticking IAC valve can prevent a start. I actually had that problem. Your symptoms appear very similar. Mine seemed to have started so I let go of the key and it died. Then no start, just cranking. Spark plugs were all wet with fuel. Once dried, the car would start with a little throttle. Hold the throttle to warm it up a little and it would stay running without a problem.
When the engine is warmed up, the IAC valve is open only a little bit. When the car cools off, the oily residue on the valve becomes thicker and causes it to stick. Normally the ECU will open up the IAC valve upon start-up, especially on cold start, since a bit more fuel is injected on start-up. But if the valve is stuck, engine will get flooded. As soon as the throttle body gets a bit warmed up (since coolant is passed through it) the oily residue on the valve will become softer/thinner and the valve will open up.
After a cold start the idle will be a bit higher, around 1200RPM, then the ECU will close the IAC valve a bit and the idle will fall to about 850.
Did you manage to start the car with a little throttle?
As for the coolant temperature sensor, here are some resistance values:
3000-4500 Ohms for 10 Celsius
2000-3000 Ohms for 20 degrees Celsius/68 Fahrenheit
1500-2000 Ohms for 30 Celsius
900-1400 Ohms for 40C/104F
Just disconnect the wiring and measure the sensor's resistance. Values come from a chart in the Haynes manual. Tolerances are small so you really need to hit those intervals. There is also a note to handle the sensor with care, since malfunction in this sensor will mess up the fuel delivery quite a bit.
I took my IAC off this morning. It's not stuck now anyway, it may have been before I removed it and cleaned it.
I tested it for the 20.4 ohm resistance reading and also for operation.
My questions is should the IAC be open or shut on 70 F day when I turn the ignition on?
Right now, its partially open when de energized and when its energized ie I turn the ignition on it shuts. Is this the way is supposed to work?
My temperature sensor looks fine. Checked ohms
There is another sensor below the distributor. It has one green wire running to it. I can't find it on the Haynes electrical diagram. But mine never was connected. However on my other corollas it is. Off hand, pls do not go to any trouble, do you know what that is? Thanks
did you check if there is any blockage in your exhaust system?
that happens to my neighbor one time, we tried to troubleshoot his starting problems for days until we realized some stupid animal has cummulated junk in the exhaust pipe because he went on vacation, leaving the car at home without using it for a couple weeks LOL
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