I have a 97 Toyota Camry with a 2.2l engine and auto trans. I have a crank no start. the car ran ok the day before it died. It has had misfire condition a couple times a week before this happen and timing belt and is in place. I have replaced the cam and crank shaft position sensors. The pump doesn't prime while in the on position. The pump turns on while cranking but not in the on position. Spark tested came out good and ECm works on another camry. If i manually ground the reley pump comes on in the on positon. any advice would help. thanks

 

Did the car run OK just before final shut off, meaning is it possible the misfire caused the timing belt to skip a tooth?

What kind of misfire, back fire through intake or exhaust or just a miss?

The fuel pump will only run when the engine is running or cranking over, NOT when the ign key is in the ON position.

Have you checked all the fuses, including those behind the drivers side ash tray?

 

Yea it ran fine before shutting off. It could be possible that it jumped timing. i havent checked that yet. also it was just a miss fire. i think it was #1 spark plug wire because when we pulled it out to do a spark. Also the crank sensor might have something to do with it too because it was reading 2090 ohms vs factory spec of 1600 ohms max. The cam and crank shaft positon sensors have both been replaced. the pump does turn on when the key is in the on position. when i replaced the pump, a couple of months ago, with the key in the on position the pump primes and then in the start position it fired right up.

 

Have you tried starting the engine when the fuel pump is jumped?

What happens if you apply some throttle when cranking?

It is not normal for the fuel pump to run with the ign key in the on position. The circuit opening relay that controls the fuel pump should prevent this. Otherwise the pump could keep running after an accident (assume engine quit during accident).

If a "hot" spark at all plugs and timing belt not slipped, then maybe a fuel issue.

Obtain a section of rubber hose, use this as a stethoscope to listen for injector clicking noises when the engine is cranking over.

 

thanks for the respond. I have tired jumping the pump, spraying starter fluid into the throttle, and when applying throttle into while cranking nothing happens. Kept cranking it yesterday and it started right up. It weird. Fuel trims look rich on it. I don't know why it started up yesterday and didn't weekds before.

 

Fuel trim as in using an ODBII scanner or black smoke out the exhaust pipe.

Has the outside air temp changed, the engine uses a coolant temp sensor to set cold and hot start injection pattern.

Fuel pressure too low resulting in engine needing a lot of fuel pump on time to build up pressure? There is a fuel pressure regulator next to the pump in the tank.

Other issues could be intake air hose clogged (typically not a issue unless mice build a next in the filter housing), bad MAP sensor (seldom fails), A/F sensor (but should start anyway), injector issues (not common).

Coolant sensor failure is reasonable common.

The fuel can filter seldom plugs up and would show itself in poor driving-hesitation-low power.

 

Yea temps have change. It's not as cold. i was leaning more towards the ECT but with the scanner ECT was up around 185 degress. Is there another sensor that controls the temps. Fuel trimw as plus 19 something. wasn't sure if it was long or short. Also when i tested map sensor it has the 5 reference volts and when i did applied vacuum to it it seems backwards according to the manual. with no vacuum applied it had higher voltage and with more vacuum applied voltage drop. not sure if it's suppose that way or vise versa. air hose and everything looks good, took that off while doing test and everything is clean along with air filter. also when the car was running it didn't seem to have any drivability issues. other then the missfire on start up. thanks for the input.

 

185F sounds right, can you check it again when engine cold to get the two extremes in operation? There is only one ECT sensor for the computer.

Thought in theory the fuel system was supposed to shoot for a fuel trim of zero. If a positive trim number the system is trying to compensate for an over all lean fuel ratio. However there are some references to a difference of 38% being normal. Abnormal operation should cause the P0171 or P0172 code to be tripped for lean or rich fuel trim.

Issues that can cause a lean mixture: low fuel pressure, intake air system (you checked this), A/F sensor (your code reader should be able to check voltages), ECT sensor (seems OK at least when coolant hot), injector issues (engine seems to run OK) and MAP sensor.

Thought MAP voltage for computer was calculated by subtracting the voltage drop from the 5 volt reference. The larger the drop, the smaller the MAP voltage for computer.

Have you tried pumping up the fuel system manually before cranking, ff the throttle is closed the injectors should be off. Thus no fuel will be injected during this time.