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Discussion Starter #1
2001 Solara 3.0. 200,000 miles.
Car runs good when warm. Summer time starts great. Now that its cold in Wisconsin. It will start really hard. Will just crank to begin with. Pump gas at it will sort of backfire a little. Then starts and dies. Restart same way and it will idle low. 500 rpm. If you try giving it gas it stalls immediately. After only a minute you can rev it up and it runs great. Once warm it has noproblem idling. I replaced fuel filter. Cleaned mass air flow sensor. Timing belt replaced 2 yrs ago. I see other sites talk about a cold start injector. I dont see one?
 

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I see other sites talk about a cold start injector. I dont see one?
The 1MZ-FE V6 in your Solara does not have one.

These symptoms are what my Avalon did when the fuel pump died:
Will just crank to begin with. Pump gas at it will sort of backfire a little. Then starts and dies. Restart same way and it will idle low. 500 rpm. If you try giving it gas it stalls immediately.
 

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Discussion Starter #5
Can you do some testing with scan tool?
Possibly. Buddy has a snapon scanner.
I took a shot at fuel pump. Changed it and plugs. Still hard to start when below 30 deg outside. The temp sensor was repkaced this summer and tests ok. Took it to a shop 2 weeks ago. They cleaned the mass airflow and charges 125 bucks.
 

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Discussion Starter #7
Can you post engine parameters taken from scanner?
I will when I get the scanner. As a note. I was a mechanic many many moons ago. So I should understand what you are looking for when needed. I have been considering buying a scanner on ebay. But need to investigate more.
 

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Discussion Starter #8
Think I got it. ... I ws going to change the injectors started taking thins apart to remove the upper intake. Found s electrical conector was not plugged all the way in. It went to what I would call a solinoid actuator. Actuator had vac hoses and one went to the end of the intake. It is a AIR CONTROL VALVE. So that makes sense. I sm guessing that valve closes when cold starting. Giving more fuel and less air. I will try it in the morning.
 

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1995 Camry LE Wagon
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After only a minute you can rev it up and it runs great. Once warm it has noproblem idling.
I think you need to verify the fuel pressure at cold start, even though the pump is new. If you can get a free loaner fuel pressure gauge from auto parts store I'd start there.

If pressure is within spec at attempt start then look to why you're getting initial no rich mixture. Intake air temp sensor?Or maybe somehow throttle plate open for too much air? If not full pressure at cold start then look maybe at sticky fuel pressure regulator.
 

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1995 Camry LE Wagon
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I have another theory that would be cheap and easy to test - water in the gas. If this happens only when the temps are below 32F there could be just enough water in the fuel that it will partially freeze and restrict flow. When the pump starts it will exert enough flow that will clear the partial blockage - seems to be in about a minute in your case.

Anyway, put some gas line antifreeze into the tank and run the engine enough to get the AF in the entire system. Then see if you have the same problem.
 

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Should you decide to try the gas line antifreeze, read the bottle carefully to determine the type of alcohol it contains. The more prevalent and cheaper is methanol-- I will NOT put that in any of my vehicles. Isopropyl alcohol is by far the better choice. The bottles are typically red and yellow. As best I recall, the yellow is the isopropyl.
 

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Discussion Starter #13
No luck getting my hands on a scanner yet. I forged on buying parts. Dumb? Yes... but it is about beating this now...So .. New fuel pump (just the pump). Fuel filter. Mass airflow. Injectors. Plugs. Wires and coils. (Broke a coil checking it out). Question now (and I think the problem) fuel pressure. Looks like the spec is 44 to 52 psi. I have good steady 52 lbs running. But the pressure drops to 0 psi after shutting off. Within a minute or so. Shouldnt it hold at least some pressure?
 

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Yes, I beleive that modern FI systems do hold some pressure. However, more to the point, the pump should start and prime the system when you turn the key to 'ON', before cranking. This may be the problem.
 

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But the pressure drops to 0 psi after shutting off. Within a minute or so. Shouldnt it hold at least some pressure?
Yes. My Camry's spec is hold at least 21 psi for at least 5 minutes. The new pump should have the anti-drain valve in it. Is it possible you have a fuel leak?

Did you test pressure cold (your problem area) and hot to compare?
 

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Discussion Starter #17
I thought I read somewhere that these cars only run the pump when cranking engine. I checked the relay. No power to relay coil with key on.
 

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I thought I read somewhere that these cars only run the pump when cranking engine. I checked the relay. No power to relay coil with key on.
Yes, the ECU must see cranking signal (not ignition signal) before starting pump. I think the signal comes from cam position sensor. You can jump the relay to get pump working without engine crank, but you already know you have full pressure at cranking.

You need to solve fast pressure drain down with engine off. Locate the pressure control valve and see if it's leaking through the vac hose.
 

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Discussion Starter #19
Well after all is said and done. Looks like the temp sensor I replaced last summer was crap. Finnally got a shop to put a scanner on it. Cold it was reading 173 deg. Got a TOYOTA sensor and now it starts like a dream.
 
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