01 5vz r150f no check engine light

As the title states

I have a 2001 RCLB base model... 5vzfe engine, r150f 5 speed manual transmission, 2wd truck

I purchased it for 500 dollars, when I bought it the engine started right up with ether

I tried doing the same thing to show my buddy the truck worked but the negative terminal was too loose and it started arcing... we gave up trying when this happened

Fast forward to now I put a new tank and new complete fuel hangar assembly

I tried to start but the check engine light never came on and the engine never fired

I visually inspected the ecu and didn't find any burn marks/shit stains

The aftermarket alarm has been gutted and everything returned to original wiring

I've checked fuses and found none that were blown

I make note of the light because when it was running the light was in fact illuminated

 

Ecu part number 89661-0C291

 

Run through these diagnostics. If failed, give us more details about what happens when you turn the key forward. Like, it turns over but no fire? Also, if you replaced the tank, have you checked the fuel pressure to make sure the pump is working? Are cylinders getting spark?

https://www.youtube.com/watch?v=0jWouSQYTnU

 

Ok, the engine is turning over, and all the electronics on the "cab" side seem to be working fine

I put a test light to the injectors

We have injector pulse

I pull a spark plug lead and it's arcing on the grounded intake manifold

It's getting spark

I took the fuel return line off and turned it over

It's getting fuel

On starting fluid it weakly lights off very briefly

 

Only three basic things are required for EFI systems to run:

- Fuel delivery at a specific pressure
- Metered air, so ECU understands fuel/air ratio
- Effective spark, properly timed

All of that to create a controlled explosion, and of course requires a fully working battery, and a working throttle body.

You're seeing explosion when you use ether which suggests you're getting spark enough to ignite things. You naturally should be bringing air in, although whether it's being metered correctly is another story. Riddle me this: Why do you think it is you're getting explosion with ether, but not with gas?

You say you're seeing fuel on the return line. That doesn't mean the fuel rails are seeing enough fuel pressure. It doesn't mean the injectors are actually spraying as much as they should, or even spraying at all.

That's about all I've got for you. I'd be curious to know a lot of things. State of the plugs. If the coil packs aftermarket or OEM. Whether you cleaned the MAF with proper MAF cleaner. Whether you checked the throttle body is acting as expected. Whether you are 100% certain the fuel pump is good, and the injectors are spraying - note: This likely won't be something stupid like fuel filter.

The plastic parts of the fuel lines in these trucks supposedly contained soy, and several cases of mice chewing them up near the tank on this forum, reducing fuel pressure, screwing up emissions system, causing leaks. Could also explain this problem.

I'd dick around with checking the coils and plugs, may as well replace with new NGK or Denso plugs, and while plugs are out, spraying a little gas into each cylinder along the way and trying to fire up after.

My money is on something with the fuel system. Pump, compromised lines, or otherwise. But over the internet, it's just a crap shoot, ain't it? The fact it fires with ether as fuel speaks volumes to me for some reason.

 

PS - these trucks are apparently really sensitive to non-OEM parts, as stupid as I think that sounds to some, we've seen it several times.
Especially coil packs, O2 and MAF, and we've even seen it with some injectors. Knowing exactly what the previous owner has done to replace would be helpful.

And I guess checking timing is worthwhile too, but I wouldn't expect it to fire correctly, even weakly, if timing was off.

 

When I did injectors, I definitely seemed like it took a while to get full pressure to the injectors. Like 10 miles or more…..
I would have definitely slapped a new sending unit and filter in, if I did all that work dropping the tank

 

Check the spark plugs to make sure they are "double prong." I think it's dual ground.

The V6 has three coil packs, and three plug wires. You've verified spark on at least one. I assume you did all 6?

The MAF should be a denso brand. The coil packs should be denso brand. Buy everything you throw at the truck from rock auto. Do not buy anything from ebay or Amazon

 

The tundra has the original toyota denso coils and maf at 270k miles... idk about the o2 sensor

I have some newer aftermarket coils, like new ngk wires, like new denso 5vz specific double platinum plugs

I'll toss all that on and report back tomorrow

I'll also see if I can get a fuel pressure guage on it

I'm more concerned with the lack of cel... If the bulb is good and the ecu is fried what's the point with all the hardware

 

I seriously doubt you managed to fry the ECU, but if so, you can still buy replacements at https://parts.toyota.com if you just plug in the number. You may need to remove the hyphen in the part number to get it to show. It seems like it takes water damage to really nuke them. The electrical system is well-fused.

RE: Fuel pressure. Before you do anything wild, do one test. Turn the key to ON position without starting it. Fuel pump should engage while in ON position, wait 3 secs, turn the key to OFF for a few seconds. Then back to ON with no start. Repeat a few more times, in theory, should build up to whatever the highest pressure is the FPR would allow. Then try to start after half a dozen cycles. Does it fire up?

 

The truck is at my buddies house I'm not with it anymore

I have it's like 1600 bucks... used they can be had for like 150

I've had a personally high failure rate for ecus and I always chase my tail doing everything before realizing it

Where do I put the fuel pressure guage at?... just anywhere before the fpr up to the pump?

 

This is not true of the early trucks for sure. Pump only runs when cranking if truck fires pump stays on if truck doesn't fire pump turns off.

 

Yeah I noted that with the return line disconnected fuel didn't start flowing till I cranked it

 

In this case, anything you can do to stop spark, then crank, should effectively do the same.

 

Unplug the passengers side coil packs, and it will kill all 6 plugs.

Been awhile since I've been in the fuel rail of the V6, but I don't see why you couldn't pop the injectors off, and then smooge some air line in the 6 injector holes on the rail and run the lines to a bucket.

Here's a link to pictures of the top of the engine with the throttle body off, the intake plenum off, and fuel rail exposed.
https://www.tundras.com/threads/tundra2s-lifetime-project.65626/page-2#post-1824562

 

Here's a link for coil packs, and coil pack testing.
https://www.tundras.com/threads/tundra2s-lifetime-project.65626/page-2#post-1843425

 

Furthermore, @Brynden29 had to test pressure on his rig trying to diagnose a weird ass "moving target" issue after a rebuild. Over here: https://www.tundras.com/threads/multiple-misfires-after-rebuild.110071/

He may be able to offer insight into how/where he tapped off to test pressure on both rails. I believe there are OBDII apps for the smartphone with a wireless dongle that will also give you the information as the ECU is seeing it.

 

I don't know how the V6 layout is, but I tapped into the feed line for my fuel rail. I bought a fuel tester kit from Amazon. It had all the adapters that I needed:

$28 BETOOLL 0-140PSI Fuel Injector Injection Pump Pressure Tester Gauge Kit Car Tools (Master)

https://smile.amazon.com/gp/product/B00VV29NHM?ie=UTF8

 

Huh, just stabbed a fuel pressure tester inline with he fuel feed line and nothing... no fuel flow

Going to have to supply 12v directly to the pump

Anyone know where the fuel pump relay is?

 

LMGTFY (but also, I think it's R4 in the engine bay box, also check your TAIL, IGN 1, IGN 2, GAUGE fuses under dash, and any EFI, A/PUMP fuses you may have in engine bay):

https://www.youtube.com/watch?v=le7DJ_DPQQY

 

Both fusebox covers are gone, on my tacoma it was under the dash and not labeled... figured it would've been the same here

 

Fuses are under the dash ftmp. Fuses and relays in the engine bay. You should really get a replacement cover for both, especially in engine bay, to prevent corrosion.

Meanwhile, see attached, and have fun. (page 493)

 

I'm going to pull the plugs and wires right now

(This is with a drill battery plugged straight into the pump)

 

In an exercise of futility I replaced all the fuses, no difference

 

Did I ask you if you already pulled the ECU from behind the glovebox, pop its clamshell open, and check for water damage?

Did you have someone jiggle the power cables coming off the battery while turning it over? And check all the grounds?

I'm at a loss. If it's cranking, injectors are pumping fuel, spark is jumping from the plugs, you have everything you need to make ignition, assuming timing isn't FUBAR.

Sure, you'll idle funky if the engine/ECU can't measure how much air is coming in, but you'd still technically fire off.

 

I have, found no damage... replaced it anyway

No difference

The engine is cranking like it has good compression... I don't suspect timing

 

Wait - I just re-read last couple posts.

Are you saying the only way you get fuel pressure is if you have a battery pack on it?

Have you tried cranking it with the fuel pump lit up by the battery pack?

 

Also, not sure if these trucks would show it but did you check whether the throttle plate is actually opening when cranking and tapping gas pedal?

Or maybe manually opening the throttle plate while cranking?

 

The truck turns the pump on with the key

Just didn't keep it on for long enough for me to mess with my faulty parts store loan a tool

 

The 3.4s have an actual cable throttle body