My mechanic said it isn’t registering any codes when it does this.
The light does not have to be on for the computer to have stored codes. Lack of a light does not mean there are no codes. However, it’s also true that when you’re starting the car, or trying to, the ECU won’t store codes. I has to ignore the signals until the engine gets running or you’d constantly have a light on.
It’s very possible that your igniter or something else in the ignition circuitry has become heat sensitive. Again, I’d try a heat gun. Since the engine apparently gets turned over by the starter (if I understood your most recent posts properly), my earlier guess about a bad starter would be incorrect.
If he were to leave the car in the shop overnight and then take a heat gun to the distributor, he might be able to duplicate the failure. If memory serves, this is a distributor based system.
It sounds like your mechanic has verified there are no stored codes. If there were, it could have provided a clue, and saved some time. Alas, back to the drawing board I guess. It will be difficult for you mechanic to diagnose until he/she can test it while it is failing. Are you able to give the car to the mechanic for a week, let them drive it to and from work? Replacing the fuel pump wouldn’t be a wise thing to do unless it was verified to be the problem. A fuel pressure test is the way to make this determination, but it might have to be done when the problem is occurring. The only other thing I can think of is a problem w/the O2 sensor(s). The engine cranks ok, right? Just doesn’t catch and run? The O2 sensors don’t do anything when the engine is cold. Instead the computer uses some pre-calculated parameters for controlling the amount of gas to inject. Once the O2 sensors heat up, then the computer uses the O2 sensor to determine how much gas to inject. Maybe something will all that isn’t working correctly.
Thank you, MountainBike and George SanJose,
Haven’t been able to get it back in to the mechanic but hope to next week when the weather is warmer. In answer to your questions about what noises it makes when its trying to start – I’m still not sure. Sorry, not a car person. Will try to pay better attention next time it happens.
There are 4 types of DTC’d but the ones detected by a generic code reader are one of the first two types. The first type is a one trip DTC and it will set the check engine light (MIL) the first time it is detected. The second type is the more common and will only set the MIL if it detects the failure on two successive drive cycles.
Both types are usually readable within either 3 or 10 drive cycles from the last occurrence, so if you did not get to your mechanic in time, they could be erased by the time he checks for them.
The problem with just a non start condition is that the codes may not even be checked. About the only codes that would apply during starting would be the misfire codes, P0300-P0304.
I was going to mention the starter solenoid as well Mtn Bike… But this car is obviously turning over so it doesnt suffer from the VERY COMMON Toyota starter solenoid issues.
I am going to say that I think its your Fuel Pump RELAY… Go into the fuse panel under the hood…locate the fuel pump relay…and EXCHANGE IT W Another relay identical to the FPR…see if the problem goes away.
Can also be a clogged fuel filter…sounds like the issue is somewhere in the fuel pump, Fuel pump relay…or a tired or dying fuel pump motor… But start logically at the FPR first and work your way to bigger more xpensive things
Blackbird
I’m still waiting for a report back about residual fuel pressure on hot shut down. That, combined with the note that “He said the fuel is reading a little low” leaves me stuck on the fuel pump. In a fuel injected vehicle the fuel pressure (if that’s what this is about) has to be inside of the specification. And if it won’t hold residual fuel pressure when shut down this WILL cause restart problems, especially in warmer weather.
Well, Everybody, my car finally malfunctioned for him (weather finally warm enough). Every possible thing was negative so that left the fuel pump. He put in a new one and it seems to be corrected.
The original reading on the fuel pump (way back) was slightly low but he wasn’t sure about going in the direction because he felt it was so rare in a Toyota. He found an article about a Toyota in Australia that wouldn’t start if it was parked in the sun but would start if it was parked in the shade…and that one was a fuel pump.
So we feel sure it’s solved now. Thank you, Everyone, for your input.