Tundra idles fine, but won't rev up.

This question is actually on behalf of my friend.

2002 Tundra, bought none running. V8 4wd. Previous owner said it ran fine for a couple of years and then one day just died. This was a couple months ago. Vehicle is in Alaska. 243K miles.

Would start for my friend but immediately die. Confirmed good timing and recent timing belt replacement. It had P1300 and P13005 codes.

My friend took off and checked the crank position sensor 'cleaned it', replaced the battery and now the truck runs.

Ran poorly at idle but after what I suspect was the ECU re-learning, now idles perfectly, but will not rev up, chokes and almost dies when stepping on the accelerator even in neutral, won't get above 1K RPM but perfectly smooth and happy at 900 idle. No codes.

Aftermarket remote start and security system installed.

Thoughts of where he should look?

 

P1300 and 1305 points to ignition issue, however….

 

Indeed, but cleared with the battery replacement and have not come back.

 

clogged catalytic?

 

Does it respond to the throttle at all?

 

Yes, it chokes and tries to die.

 

Odd with no codes. I would think fuel delivery, MAF sensor, TPS, throttle not opening with command. “One day just died” speaks to an overt failure rather than a simple maintenance issue. Bad gas? maybe. Needs plugs? maybe. That link I shared with similar codes ended up being O2 sensors, also worth a look.

 

Question on the throttle, I though our trucks where fly by wire....but there is a throttle cable? I did confirm same issue when manually moving the throttle under the hood by pulling on the cable.

 

While at idle, stand by the tail pipe, then have someone rev it. If you hear hissing, it's a clogged cat. If it doesn't, check that off the box of troubleshooting. Have had a Toyota and a Ford do that in my lifetime

 

2000-2002 have throttle cables

 

Tail pipe sounds normal.

He just replaced he fuel filter even though I told him its never the fuel filter. No change.

 

Coil packs. Can you let him borrow your coil packs, just to test?

 

No, we are about 3000 miles apart.

 

A coilpack or packs are probably shot. Could also be a bad MAF. But ill put my $$ on bad coilpacks.

 

That's rough. I'm thinking ignition, and for some reason, my gut is telling me this is a detonation issue, not a fuel delivery issue.

Granted it could be grounding also, I'd be tempted to toss a temporary ground from the batt to the block just for shits n giggles. But ... I dunno. If I'm throwing parts at this, and fuel filter is done, and you know the fuel pressure is high, and plugs are correct model, and this is recent onset, I'm less inclined to blame the throttle body (although I'd probably clean it and remvoe neg batt cable) and the MAF (although I'd clean it, and remove neg batt cable, and test resitance per FSM), and think it's more related to electric fire.

 

So one weird thing....there is a wire soldered to one of the coil pack wires, Drivers side, closest to the the front....leading into into the firewall. Some kind of aftermarket BS obviously.....any idea what?

We don't know what the fuel pressure is, just that it has enough to idle fine at least. He is checking plugs next.

 

Post pics

 

The truck that wouldn't run with ignition codes has a sketchy wire soldered to a coil pack? My guess is some kind of aftermarket tach setup?

 

Hi everyone,

I am Aerindels friend with the aforementioned tundra.

My recent updates:

• This morning it’s running rough and dies within 30 seconds of starting. It seems worse with the colder temperature. It’s 22 degrees this morning.

• I have another friend up here who let me swap coils with him and it ran exactly the same.
• I swapped in brand new nkg plugs with no change.

• I ruled out the pvc by covering the port going into the intake.

• I realized I didn’t check the crank position sensor in the hot or cold range, it was somewhere it between at around 68 degrees and I got 1910 ohms. I checked it again this morning in 22 degrees (which I believe is 8 degrees warmer than the cold range values provided) and had a similar reading. But when I reinstalled it, the truck seemed to run worse.

• Also, still no codes to date since my battery replacement

• My throttle seems to track appropriately on my obdII reader when press down on the pedal, so this makes me believe the ACS (actuator control sensor) is good?
  
  
• Also no whistle on my tail pipe, is it still worth trying to unbolt my rusty exhaust to see if it improves?
• I also ran a jumper cable from negative battery terminal to the engine.
• I also checked the ecu for obvious water damage at it looks good.

Thank you all for the input.

 

The sketchy wire is disconnected for now, but went into the aftermarket security/remote start system.

 

Welcome to the forum! Sorry it's for some problems.
When was that Timing belt replacement? Problem existed before this? or sometime after?
The CRANK position sensor was replaced? How's the CAM position sensor and it's wiring look? Often times the wires get routed incorrectly after a TB change and it gets rubbed through by the belt.
MAF sensor and throttle body both look good and have been cleaned?
Any aftermarket sensors in this mix? Most of the sensors are voltage dependent and Toyotas don't play nice with many of the aftermarket offerings.

 

Thanks for the welcome!

The timing belt was done in the last 30k. I checked the timing marks.

The guy I bought it from owned it for about 4 months and got it from the guy that did the timing belt. It worked up until one day he went to start it and all of this started.

All the sensors are stock Toyota and look original, with the exception of a few of the coil packs.

The MAF sensor is clean and Aerindel tried running his truck without his plugged in, it ran mostly okay and was still able to rev up fine.

The cam sensor was within tolerance.

The wiring for both look good and only one of each wire is grounded and there is no continuity in between the two wires feeding the respective cam sensor and the crank sensor.

https://youtube.com/shorts/sGc_3hNykoQ?si=7wK6Q1Sp-UUdA7UO

Here is a short video of it running yesterday before it smoothed out. It took about 15 minutes of idling like this before it was at normal smooth idle.

 

Wow, how are there no codes for that? Sounds like it's misfiring, or really out of time.

 

Zero codes, it will smooth out too after running for a while.

I took off the timing belt covers and visually verified all the marks which were spot on.

 

O2 sensors? Have they been checked? Vacuum leak? I hear some sputtering and chuffing in there.

 

I have not yet checked any o2 sensors.

I sprayed carb cleaner around the engine with no change. Any other good way to check for vacuum leaks?

 

This is a potential problem. Have you tried @Aerindel's coil packs?

 

I tried coil packs from a working truck with 140k with no change.

 

Try swapping throttle bodies? The manual cable goes to the throttle body which has a position sensor and a throttle motor on it.

 

Surprised nobody has mentioned a fuel pump yet. A failing fuel pump will sometime supply enough fuel to run and idle but not enough to rev. It also gets worse with the cold as the motor runs rich/demands more fuel the colder it is.

Do you have access to a fuel pressure gauge? I am not familiar with the 1st Gen fuel setup but there is sometimes a Schraeder valve (think tire pressure valve) on the fuel line to check pressure. Perhaps someone more familiar can chime in on that particular detail.