Doesnt want to start but runs fine once started

It’s a 2002 Sequoia runs fine if you can get it to start if changed fuel pump, cleaned fuel tank. Changed fuel pressure regulator, cleaned and replace o rings on injectors. Checked all vacuum lines. If I spray starting fluid in throttle body it’ll start sometimes, oh and I cleaned and checked evap cannister and blew out all the lines. If anyone has an idea as to what they think this might be please let me know.

So it turns over but won’t start, correct?

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Any check engine light? A bad camshaft position sensor can cause this, but would most likely throw a code.

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Right turns over and will start with some starting fluid. But without starting fluid have to leave the key on for 10 min to an hour depending on the day

No check engine lights no codes I’ve scanned it several times

Are you basing the fuel issues on readings from a fuel pressure gauge? When you turn the key, the pump will only run for a few seconds and then shut until the key is turned again, so not understanding leaving the switch on for a hour. Fuel or spark, or proper fuel ratio determined by the computer and sensors.


I wonder if the pump comes back on for a few seconds when the fuel pressure bleeds down - and eventually there are times when there’s enough fuel and fuel pressure at the engine for it to start.

Doing the “key dance” a few times and then turning the key to Start might enable it to start quickly.

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It sounds like it is starting w/a too lean mixture. I’m presuming this problem is worse on a cold start, not as bad on a warm start. Is that true?

A couple of possibilities to consider, given the engine starts consistently w/ a shot of starter fluid:

  • Fuel pressure not holding when engine is off: fuel pump (more likely), or injector (less likely).

  • Engine coolant temp sensor function has failed. This is how the engine determines how much fuel to inject for cold vs warm starts. Basic scan tools can usually display that parameter. Should be near ambient temp on cold starts, 200 deg F on warm starts.

  • Ambient air temp sensor has failed. Likewise, use scan tool.


It doesn’t matter if it’s cold or hot.
Its random

Scan tool shows no codes nothin

No check engine light I’ve scanned it several times while running and shows everything is fine

This truck has the early type of electronic throttle control, will the engine start if you press the accelerator?

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If you aren’t certain about the spark quality during cranking, that’s the first thing to check b/c it is fairly easy to do. A few years ago I had a orange-ish spark develop on my truck that was preventing the engine from starting. The spark should be bluish-white. Problems with the sensors that determine engine rotation angle will sometimes prevent starting but not throw a diagnostic code, and can be intermittent.

After that, besides the ideas above, consider having your shop do a fuel pressure hold test. This will determine if the fuel pressure is leaking down, either via the fuel pump check valve, or a leaky injector.

All the routine maintenance is up to date right? Spark plugs, engine air filter, battery and charging system test good, etc.

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What do I know? But if it starts “sometimes” by spraying starter fluid in, guess that suggests a lean fuel issue as suggested. What could cause a lean fuel issue at start up? If I were just replacing parts I’d be thinking engine temp sensor or air sensor out of whack. Replaced everything for fuel pressure unless the pump isn’t coming on or an injector is leaking. But that wouldn’t really fit the “waiting an hour” issue. Still need to know fuel pressure when not starting. Always possible to get faulty parts.

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Its not the spark I checked that’s fine

Pressing the throttle doesn’t help

I have changed everything except the idle air control valve. Because it the most expensive so I’m gonna change that next and see what happens