Hard time starting after fuel injector replacement

Howdy fellas,

The rig: 2003 Tundra SR5 v6 3.4L 2WD

Background: Recently had a misfire issue (P0306) and rough idle. Replaced valve cover gasket, o-rings, spark plugs, plug wires, and coils (NGK). Still idled rough but went down the road fine. Thanks to a suggestion on my previous post I put in refurbished NGK fuel injectors.
After the fuel injectors went in the truck definitely idled better (still a touch rough occasionally) but went down the road great.

Issue:However, after I switched out the fuel injectors it has had a really hard time starting. Turns over for about 10 seconds and only starts if I give it a fair mount of gas. Once it has fired up its running fine.

Today I cleaned MAF sensor and pulled off throttle body and gave the butterfly valve a good cleaning. It's still having a rough time starting. Maybe check valve on fuel pump?

Anybody have this issue? Or any good ideas?

Thanks!

 

How old is your fuel filter?

 

Maybe check your fuel pressure, could have a failing fuel pump.

 

Could also be a poorly "refurbished" set of injectors. I once bought a refurbished starter for an Acura only for it to die after 13 months. I went new the 2nd time.

I hope this isn't the case but the timing leads me to think it might be.

 

No record of changed fuel filter from previous two owners and I have never changed it so assuming the age of the car - I think that'll be my next job. From what I've read online the fuel filter on '03 is not in the tank...? Would really like to not have to drop the tank out haha.

I'll check the fuel pressure. When I switched out the injectors the fuel lines seemed to have quite a bit of pressure. Of course that doesn't mean its the right amount. Also, the issue is only when it starts up - idles ok after that and goes down the road fine. So the pump seems to be working after initial start.

Certainly hope it is not the injectors that would be a bummer. Also they are denso not ngk from original post - lifetime warranty on the refurbished ones. Fingers crossed I didn't waste my money.

 

Fuel filter is under driver side cab area. Parking brake pedal adjustment is there also.

 

Filter is under the drivers side seat under the chasis. A small little black canister.

 

how old are the O2 sensors?

 

Ok maybe I will try and change the fuel filter since it is fairly accessible.

Im not sure - the O2 sensors have never been changed so I would assume the age of the car.

 

Just so you know, O2 sensors have no effect on inital start-up.

By your description, it sounds like you have a vacuum leak somewhere, or an injector (or multiple injectors) that is leaking fuel into the intake ports and flooding the engine while it’s shut off.

For the vacuum leak check, you can idle the engine and carefully spray a bit of starting fluid in short bursts around the intake manifold to see if the idle speed / sound changes. Do this outside and avoid spraying near the air cleaner intake. Any change is RPM indicates a vacuum leak.

For the leaking injector theory, a borescope type camera is useful in finding the leaky injector(s). Shut the engine down, remove the TB and inspect the ports for wetness, or drips from the injectors.