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Helpful to pump gas pedal to get car to start

Bought our RAV4 (V6) new and not a bit of trouble until 3 months ago. At 35K, it started to take a second try before starting. Once started, it ran great and always started after shopping or a movie, …until recently. If I do not touch the gas pedal it takes 9 tries before it starts. Cranks like a champ. If you pump the gas pedal, you can get it start in two or three tries. Time is a factor. If stopped a short period of time, the car starts on the first try. Leave it for 4 hours or more and it takes 8-10 tries or once again, pump a few times and the car starts in two or three. Recently, I put a 16 ounce bottle of Seafoam in a 3/4 full tank and am planning on trying a fuel systems cleaner and premium gas when refilling. Please do not tell me this may be the fuel filter, which is part of a $600 fuel pump, located in the gas tank. We typically get gas from a large volume national chain. Never any sputtering or hesitation.

What does it do when you turn the key just before the start position and do that a couple of times? Does it then start up like normal?
I ask because the fuel pump gets primed by running it for a second or two before starting. If that isn’t happening, it may be something electrical.

Have you noticed any black smoke from your tail pipe when the car finally does start?? After you get it running does it run rough for a few seconds??

Run back to the dealer and stop trying to fix this. This is a failure that likely is under warranty or undisclosed recall. Approach the dealer with righteous indignation and serious insistence for a free repair. Did I say right away? And don’t mention the seafoam. Or for that matter anything at all, just that it does not start right and it is too new to be a problem unless the manufacturer had a mistake. There is absolutely no reason to use the gas pedal at all to start this car, something has failed and the dealer needs to fix this under warrantee.

Are you pumping the gas pedal while cranking it, or before trying to start it? If while cranking it, try holding it to the floor instead. If before cranking it, you’re doing absolutely nothing whatsoever. Fuel injected cars completely ignore input from the throttle when the engine is not running or at least being cranked. Like pushing buttons on your remote with the TV unplugged from the wall. If you’re pumping the pedal while cranking it, it’s probably doing the same thing as holding it to the floor would do–this tells the computer to not inject any fuel, and is programmed to work like doing the same in a carbureted vehicle–it clears a “flood” condition. If this works, you may have a leaking fuel injector or bad fuel pressure regulator.

As said by @oblivion, I don’t think this is related to pumping the gas pedal. Or if it is, it is only indirectly related. It appears to me to be some fault in the fuel injection system which is yielding an incorrect fuel/air ratio at cold start. The most likely cause I’d guess is a problem w/ the cold start injector or it’s associated electronic timer. The timer meters out some extra gas at start-up depending upon the coolant temperature. Mechanics have several good ways to test it – often they disable the ignition system and listen for the cold start injector timer to to kick-in the cold start injector. Usually this causes the fuel pump to run too. Don’t try this yourself. Get someone who knows exactly how to test the cold start gadgets on your make & model.

Oh, one more thing. There’s been some gasoline recalls in some areas due to bad gas making it to some gas stations, and the bad gas clogging fuel injectors. Google to find out if this affects your area. Best of luck.

George,
Most cars now do not have a cold start injector. The temp sensor is the master control usually until the o2 sensors come online.

How many miles on the Rav 4 now? Some Toyota’s call for new spark plugs at 30K miles. My Camry is 60K miles on the plugs. Check for a dirty air filter also.

You say it takes mutiple TRIES to start the engine. Why do you stop and TRY again? wh ynot stay with the starter until it starts?

@euryale1 … I didn’t know that. Do you mean most “new” cars no longer sport cold start injectors? These used to be common. My early 90’s Toyota Corolla has one. And my 70’s VW Rabbit had one as I recall.

Have they eliminated this component now, in favor of just letting the existing injectors put out a bit more fuel at cold start based on the engine coolant temp? Do you know what model year appx the manufacturers made this transition? It makes sense, as it elimates an extra fuel injection component.

If the OP’s car doesn’t have a cold start injector, then would the symptoms reported most likely be caused be a failing coolant temp sensor then? Or would it be the ECU? Or the injectors themselves? What do you think?

Here’s some more info about the elimination of the cold start injector on Toyota engines.

On page 22 of the link below, it says starting with the 91 model year, cold start injectors have been eliminated on 3e-e and 4a-fe engines. It uses the THW signal (water temp sensor) as input, and lengthens injector pulse wide to supply enough fuel to start the engine.

http://www.autoshop101.com/forms/h22.pdf

Note: This must not apply to all Toyota engines post 91, as mine is post 91 model year, a 4a-fe, and retains a cold start injector and associated timer.

As others have said, pumping does nothing. What might be happening is that one of the injectors is leaking with the car off, and pushing down on the gas opens the throttle, letting in extra air and helping to clear out the excess gas. So get all the injectors tested, along with the fuel pressure, see if it drops off when the engine is shut off (if it does an injector is leaking).

Cold start injectors were pretty common with throttle body fuel injection, as I recall. These were kind of primitive, kind of like a fancy electronic carburetor until the sensors and other tech caught up. But with multi-port injection, there isn’t much point–the PCM just commands more fuel to be injected with the existing injectors.

@GeorgeSanJose … This was part of the transition to odb2. The old systems in some cases used a timer on the cold start. Odb2 required a faster transition to lean burn, this is also why the o2 sensors are heated normally as opposed to heating from the gasses.