Intermittent Starting Issue

I just purchased a one owner 1st gen Tundra access cab 2WD with 4.7 with 133K about 3 months ago. Truck is my spare vehicle and I use it on my days off for home depot/lowes runs.

Recently it's having intermittent starting problems where it cranks but won't start. Then other days it starts right up and runs like a scolded junkyard dog. Already went down a rabbit hole watching a forum video on a humming sound coming from underneath the intake with key in on position which was allegedly a starter problem. Needless to say the starter checked out good at the starter/alternator rebuild shop. The only plus to that sob story is I could have the intake off next time in under 30 minutes.

I've suspected the fuel pump from the beginning but don't want to do a harder no fix repair again. This is a southern truck and extra clean underneath. So starter is good, battery is good, and swapped out starter relay because it was under $10 and 30 second job.

Before I changed the relay the last attempt was a crank but no start. I swapped relay out and it started up but sputtered briefly until fuel pressure was constant. ( A few seconds) I took it to several locations that day and it started fine at each stop. I told my buddies at work I never get that lucky fixing anything! Needless to say after sitting for several days I was back to the crank no start condition. Once it's started it runs excellent and there are no stored codes and no check engine lights.

So after another crank no start again, went out yesterday and it started and ran great again. I'm leaning on changing fuel pump but don't want to unless I'm 100% sure that's the issue.

I'm having zero issues and NO codes or CEL when it's running so that's why I don't think it's a fuel pressure reg, Crank or cam sensors, other fuel relays and definitely not a battery or starter issue.

I don't have the special fittings or gauges to check for fuel pressure yet during the no start days but thinking about purchasing that setup prior to dropping the tank to change the pump.

Would rather this be a permanent problem instead of this intermittent BS.

Looking for any suggestion, help or ridicule!

 

Learn about your "new" truck: https://www.tundras.com/threads/so-you-wanna-buy-just-bought-a-1st-gen-tundra-eh.115928/

Before you go any farther, or drive the truck, you really should check and see when the last time the timing belt was changed. It's due every 9yr/90k per Toyota or 10yr/100k miles if you talk to most folks on here.

You really need to verify the timing belt is intact and in good shape. You can do this by loosening a few 10mm fasteners on whichever cover is easier to get to and taking a peek. Not shiny, not cracked, etc.

Next, I would check to ensure the crank position sensor harness - that sensor being vital to the fuel pump actually engaging - wasn't improperly routed and isn't getting nicked. Routing instructions and more details are in that thread I gave you, searching for the word "routing" on the 1st page to see it.

Does the sensor wire look routed correctly? Any signs of it getting nicked?

The definitive way from here, to isolate whether this is a fuel delivery issue (DO NOT immediately go to "fuel pump is bad"!, the starter and fuel pump are often NOT the issue!)... go to the parts store. Get you a can of starting fluid (ether). Next time it won't turn over, spray a health 2sec shot into the throttle body, behind the butterfly, and try again. If it turns over, that's good info to know.

I would also check that the camshaft position sensor, which lives behind the driver side timing belt cover, isn't being (A) pinched by the water pump nor (B) having its wires shredded by the timing belt or a pulley.

 

I was scanning the get to know section earlier and it looks to have great info.

I was planning on looking at timing belt after reading the intro even though it has a sticker stating it was changed around 100K. I am certain the sticker is legit but plan on looking anyways.

With that being said I will check out the crank position sensor to make sure I don't have any chafed or exposed wires going to the connector. I also already have starting fluid and will do that check also.

I'm still leaning towards fuel. This was an old man truck and was only driven less than 10K in the last several years and when I got it home the gas gauge was at E and I feel it hasn't been filled up in many years besides me putting it up to 3/4 of a tank. I purchased from the Son of the guy who was in his 90s and no longer driving.

 

It's quite possible it is fuel. Given it's a 2002, it does have a fuel filter. That said, the OEM filters were extremely lenient in what they allowed to pass thru. The one time we actually saw a case on here where the fuel filter was the problem, it was clogged as shit! But it was aftermarket. I have yet to see an OEM filter that's the cause of poor performance.

That said, you know the old trick with fuel pumps, right? Just like tapping a starter solenoid when the starter won't fire, you can slap the gas tank a few times on a failing fuel pump and usually get a couple more starts out of it. May be worth trying.

There's a PDF floating around here giving a layout of the fuel system. I think there may be links to it from that community info thread.

Anyway, welcome to the forum, I'm sure we can probably help you get that thing in tip top shape, but we'll also help you spend way more money than you probably wanted to once you start loving yours as much as we love ours

 

I forgot to mention that I did change fuel filter when I removed the starter for practice. Against the rules I went with the Napa Gold one since I get an incredible discount there. The one I removed was garbage aftermarket.

I also had my wife trying to start it while I laid underneath it and beat on the tank with a giant rubber mallet which didn't jolt the pump back to life. When running I have to be careful not to spin the tires this 4.7 is so strong and peppy.

This is my spare so going to look at it later this week on my days off, thanks for the input.

 

So I was able to buy the correct banjo bolt and adaptor to hook a pressure gauge up to the fuel rail where the line initially enters from the pump. When I apply 12 volts from positive battery terminal for the low and high speed terminals where fuel pump relay sits I get 38 & 42 psi fuel pressure. When I remove voltage and pump isn't running the pressure immediately drops back to ZERO. Fuel rail will not hold fuel pressure when pump not energized, so my only thought is it needs a new fuel pump because internal check valve has failed. Don't think fuel pressure regulator plays any part in this scenario when truck engine isn't running since it's vacuum operated.

Any input or thoughts would be appreciated. THANKS

 

Wish I could give a definite answer on what corrected my starting issue but everything seems good now. Changed fuel pressure regulator with no help and then the fuel pump. It started right up after fuel pump change then the next morning was long crank with no start. I disconnected the battery that morning and cleaned cables & terminals ( Didn't appear dirty) and left battery off for most of the day, hooked everything back up later and haven't had a starting issue since. Not sure if the ECU reset did something, just happy that the mystery problem is gone. Been starting and driving the truck a lot more than I was considering it sat barely driven for probably ten years from previous one owner older gentleman. The brand new looking Michelin tires on it when I purchased last fall had a date code of 2013.

 

The only chronic starting issue with my 4.7 is if I leave sit for a few days which is uncommon. The starter seems like it strains a bit, engine starts erratic like running on less than 8, smell of unburned fuel and knocking sound. I immediately turn it off/restart. The knocking has usually subsided but takes a few seconds to run properly. It's done that ever since I can remember. Seems like fuel might be leaking into a cylinder(s) and creating some type of fluid lock on a cylinder or two. Curious if anyone else experiences similar or is my truck special.

 

That's very similar to what I was having happen once it did start with the exception of smelling fuel. It would act like it was running on less than 8 cylinders as if it was being starved of fuel. Once it started it ran great, as it does now.

 

What special fittings and gauge setup did you use? Any Pics? Were you able to find a recommended post(s) or video(s) to use as a technical reference for the process and setup? Maybe you already knew how to do it.

I'm trying to figure out how to run a pressure test to solve my lean codes on both banks of my 04 AC.

 

This is the banjo fitting I bought off of Amazon;

$15 M12x1.25 Banjo Bolt Kit for Fuel Oil System (M12-12MM)

https://www.amazon.com/gp/aw/d/B0BDK9F2H7?ref=ppx_pop_mob_b_asin_title

Also picked up a generic barbed fitting from AutoZone to attach to banjo bolt along with 1/4" fuel line and pressure gauge. Hooked into fuel rail on left forward side of engine. Be careful not to lose crush washers as there are two, one on top and one under the existing bolt. Trying to upload video of setup but not having any luck yet.

 

Thanks, Cadillac....I haven't uploaded a video onto the forum yet but believe we have to upload to YouTube or the Imgur site that @Shifty talks about and copy the link from either site and paste into your post here. Somehow the video magically appears. Something like that.