Hard starting solved

2016 3.5. For 4 years starting was intermittent, dealer no success finding the issue. It would crank and crank, let off start button and push again would usually start. When did start while revving the engine could feel a dead cylinder for a few revs then it would clear up. After a day at dealership they said we think fuel pump. No codes ever triggered. Truck did not start for them a couple times but they couldn’t figure it out.
I did not change fuel pump, 4 years I would’ve thought the fuel pump would have quit. I felt an injector was leaking, flooding cylinder and losing fuel pressure.
so I ordered 6 fuel injectors from Motorman injection, refurbished. Awesome company if you need injectors.
I replaced all 6 , changed spark plugs while I had the plenum off, and trucks been starting ever since. Mileage has improved also by about 3 mpg. Thought I would share in case anyone else is experiencing the hard start.

 

Welcome to the forum. Great first post

 

I don't think one bad injector would cause a starting issue, nor do I think all six injectors would go bad. Perhaps a fuel pressure issue. I understand that you have resolved the starting issue, but I don't think a proper diagnosis was performed, thus it's questionable as to what the problem is/was. I'm surprised you didn't get trouble codes, especially if one cylinder was not firing.

This guy has excellent videos on how to diagnosis an issue.
https://www.youtube.com/watch?v=C6K37uQkbL4
https://www.youtube.com/watch?v=3KyXvdWkgOA

 

Did you buy this truck new? How many miles on the truck?

 

Nice to see that you solved your problem. Cheers!

 

Did you change the DI injectors or the port injectors?

 

I bought the truck brand new, it has 128,000 miles on it. It has spent a lot of time off road, hunting mostly.
I changed the low pressure injectors, did all 6 as I had no way to identify which one was the culprit. Besides if you take it that far apart mights well change all 6.

 

It is working now and that’s all that matters!!

 

Do you still have the old injectors? If so, can you measure the resistance of each one and see if one, or more, is not like the others?

 

And if you still have the removed spark plugs it would be interesting in seeing a photo. Usually there is an indication if a cylinder had been running poorly.

 

So I ohmed each injector , 13.5 average with one being 14.1. Thanks for giving me the idea. As for the old spark plugs I was hoping one would be different to identify the cylinder , but they all looked the same. truck has started every time now which tells me I’ve corrected the issue. I had changed the crankshaft sensor last year as I noticed a recall on some Toyotas so thought maybe they missed mine, also one shop told me my voltage was low on battery and that was my issue but turned out not true. I did run my leaking injector theory by the techs but they just shrugged their shoulders. They couldn’t even tell me which fuel circuit starts the truck. So I took a 149.00 chance my theory was correct.

 

Great job OP. Thanks for updating.