Cruiser in crawl mode please help (3 Viewers)

[BILT4ME]

Point out the harness for me ? Somewhere behind 1,2,3 I’m guessing …

View attachment 3535745

Between and underneath 1 & 2. It comes from the firewall down to the top of the head and runs forward down along the injector rail. It's about 3/4" in diameter near the back of the engine.

I think it's easiest to get hold of it from the right side of the truck.

 

[calokie]

Another update:
Checked air intake, no visual leaks, no mice around, cleaned up the MAF, and ran thru securing all distributor wires from dist to plugs.... but still sputtering after that.
Ordered Fuel filter and pump, but it'll be a week until they come in and get on the truck. And the autoparts store was out of Heet, so that'll be here tomorrow since I just bought it online.

If my link below works, I got a video of this noise....call it what you want, pop/putter/sputter/knock something like that (can hear them at 5 seconds and 8/9 seconds in the video). But, its seemingly triggered when accelerating out of a stop, nothing going on while idling.
It is in the engine bay, I just cant tell where or what it is....sorry i need more help, but does anyone recognize a noise like this in that situation?

My money is on fuel supply issue. Hopefully you get it resolved soon!

 

[flintknapper]

 

[calokie]

View attachment 3535905

Its not as dumb as the 3rd gen Tacoma exhaust routing.
EGR/Injector Harness contact should definitely be on MrEs prime suspect short list.

 

[VTOLC100]

I just had a similar issue - here is the timeline:
Friday -washed truck ( touchless drive through ) then drove truck 75 miles from 8F to ski mountain where overnight temps got to -2F plus windchill maybe -15F.

Saturday evening: (2F plus wind chill) truck started _went approx 200 yards - (did not notice no throttle response at this point). Stopped to check H and L gears and pushed Center Diff on. (First time to do this since owning the truck) VSC TRAC and VSC Off came on. Turned Center diff off. VSC TRAC and VSC Off stayed on. Applied gas, then noticed no throttle response but engine was around 1000rpm. Coolant and oil temps were mid range. PWR button was also stuck on.

Checked throttle cable- not moving when accelerator pressed but would rev when moved by hand. With pedal to floor RPM’s would go to 3500.

Managed to limp back to starting point in this mode. Went to eat and started truck 1 hr later and had throttle response. VSC TRAC and VSC Off lights and PWR still on. Left it for the night.

Sunday morning: (2F plus wind chill) - Started no problem. Got PWR button unstuck. Same issue -no throttle response and VSC TRAC and VSC Off lights still on.

Disconnect batter and pulled the EFI relay and let sit for 10 minutes. Reinstalled relay and reconnected battery. Truck started and VSC TRAC and VSC off lights cleared. Throttle response returned and truck is driving back now with not lights on so far.

Maybe there was several things going on at once, but as I cleared codes can I be confident I actually have Active Trac and VSC? Also if anyone has any insight into why there would be not throttle response and why it would then return would be much appreciated.

 

[MrErer]

I just had a similar issue - here is the timeline:
Friday -washed truck ( touchless drive through ) then drove truck 75 miles from 8F to ski mountain where overnight temps got to -2F plus windchill maybe -15F.

Saturday evening: (2F plus wind chill) truck started _went approx 200 yards - (did not notice no throttle response at this point). Stopped to check H and L gears and pushed Center Diff on. (First time to do this since owning the truck) VSC TRAC and VSC Off came on. Turned Center diff off. VSC TRAC and VSC Off stayed on. Applied gas, then noticed no throttle response but engine was around 1000rpm. Coolant and oil temps were mid range. PWR button was also stuck on.

Checked throttle cable- not moving when accelerator pressed but would rev when moved by hand. With pedal to floor RPM’s would go to 3500.

Managed to limp back to starting point in this mode. Went to eat and started truck 1 hr later and had throttle response. VSC TRAC and VSC Off lights and PWR still on. Left it for the night.

Sunday morning: (2F plus wind chill) - Started no problem. Got PWR button unstuck. Same issue -no throttle response and VSC TRAC and VSC Off lights still on.

Disconnect batter and pulled the EFI relay and let sit for 10 minutes. Reinstalled relay and reconnected battery. Truck started and VSC TRAC and VSC off lights cleared. Throttle response returned and truck is driving back now with not lights on so far.

Maybe there was several things going on at once, but as I cleared codes can I be confident I actually have Active Trac and VSC? Also if anyone has any insight into why there would be not throttle response and why it would then return would be much appreciated.

View attachment 3538437

View attachment 3538438

View attachment 3538440

No VSC on my 80 series, so can’t help you there.
And I’m still in the diagnosis phase…although I can visually see that my main harness is touching the EGR pipe, so leaning towards that issue as the @flintknapper photo above shows that is causing my throttle problem.
I did get the fuel filter and pump in too. So will run thru it all in next couple weeks when I can.

 

[suzuguru]

That "pop" sounds almost like a backfire. I would be suspicious of that main harness right next to the EGR pipe. Good luck with it.

 

[flintknapper]

That "pop" sounds almost like a backfire. I would be suspicious of that main harness right next to the EGR pipe. Good luck with it.

^^^^
Same thing that made me think misfire or timing.

 

[MrErer]

Another update:
Finally got under the hood tonight. I took the EGR valve and modulator off in order to take a peek at any issues...
And you all were pretty spot on, pics below:

You can see the EGR pipe in both pics and it was melting that harness wrap pretty good. The pipe was a little offset to the harness, but the tightening nut itself was touching the harness and created that heated rub.

I'm gonna clean it up Friday or Saturday in daylight and try and inspect the wires to ensure no further damage. And assuming I'm good there, no breaks or tears in a wire, what can/should I do to insulate that thing and prevent this again?

And finally, barring enough time this weekend, I'm still going to put on the new fuel pump and filter. Also, in the past week I ordered a new EGR valve, gasket, and modultor....so step by step I'm going to installs all those parts to see if any of those are the issue.

But, very much leaning to the harness as my problem now that I've seen that damage, just hoping it was the rub and heat and nothings melted in there tho. But again, what can I do to insulate that thing?
I was thinking something like this, the exhaust wrap stuff ...? Design Engineering DEI 10129 DEI Titanium Exhaust Wrap with LR Technology | Summit Racing - https://www.summitracing.com/parts/dei-010129?seid=srese1

 

[jwbc84]

I used that on my EGR tube. Then wrapped the harness in tape and an aluminum shield. I should be good now.

 

[lumbee1]

Have you considered just installing block off plates instead of reinstalling that hot pipe that will eventually shorten the life of your harness?
I removed my EGR and made my own block off plates many years ago. No ragerts.

 

[MrErer]

Have you considered just installing block off plates instead of reinstalling that hot pipe that will eventually shorten the life of your harness?
I removed my EGR and made my own block off plates many years ago. No ragerts.

Yes , but I have 2 more years of emissions testing in my state, then it’s exempt. Until then didn’t want to mess with throwing codes, etc.

If thats not the case tho…what did you do? Block off plate onto manifold, and just left EGR pipe in place and capped it ?

 

[lumbee1]

Yes , but I have 2 more years of emissions testing in my state, then it’s exempt. Until then didn’t want to mess with throwing codes, etc.

If thats not the case tho…what did you do? Block off plate onto manifold, and just left EGR pipe in place and capped it ?

Sorry about the emissions.

I removed the pipe completely, installed two block off plates, removed any hardware connected to EGR, and installed a 47K ohm resistor (I think that's right) to fool the engine and not light up the CEL. I don't know if this will show in emissions though as not ready.

 

[Marvelicious]

Sorry about the emissions.

I removed the pipe completely, installed two block off plates, removed any hardware connected to EGR, and installed a 47K ohm resistor (I think that's right) to fool the engine and not light up the CEL. I don't know if this will show in emissions though as not ready.

Pretty sure 47k is workable. The previous owner of mine obviously didn't know what the 'k' was for: he had one that was 47 ohms and said it didn't work right. I think I used 56k. The computer is looking for a value in a range, so it's not TOO critical. The range is in the FSM somewhere... troubleshooting maybe.

 

[alia176]

Since the engine is stumbling while idling, I'm thinking a vac leak might be happening. I'm not sure how old the vac hoses are and there are quite a few of them under the intake. Might the OP be able to borrow a smoke tester to see if smoke comes out of one or more of the vac hoses?

Secondly, I like the idea of installing a fuel pressure tester to see what the fuel is doing. It's hard to know the cause/effect unless some objective data can be obtained.

Thirdly, can the vehicle move normally in 4hi with the CDL engaged? We want to rule out the center viscous coupling by doing this test.

 

[MrErer]

Since the engine is stumbling while idling, I'm thinking a vac leak might be happening. I'm not sure how old the vac hoses are and there are quite a few of them under the intake. Might the OP be able to borrow a smoke tester to see if smoke comes out of one or more of the vac hoses?

Secondly, I like the idea of installing a fuel pressure tester to see what the fuel is doing. It's hard to know the cause/effect unless some objective data can be obtained.

Thirdly, can the vehicle move normally in 4hi with the CDL engaged? We want to rule out the center viscous coupling by doing this test.

Some of the Vac hoses look like theyre from 1997....so yes gonna pull and replace those. I have some 3.5 and 5.5 sized hose from my FJ60 project around, are those the 80 series sizes do you know? If not, nbd thats an easy find for me, got my giant FSM in the garage.

Gonna run to auto parts today for some of the cool tape to add to the harness, and I'll see if i can rent or buy a smoke tester from them.

And honestly, regarding the 3rd, when this first started a couple weeks ago now I was getting the same hesitation in hi/lo cdl on/off, kinda all around. But at one point stranded in a parking lot, 4Lo was moving me the best, not normal at all, just seemingly less hesitations.....

 

[alia176]

Some of the Vac hoses look like theyre from 1997....so yes gonna pull and replace those. I have some 3.5 and 5.5 sized hose from my FJ60 project around, are those the 80 series sizes do you know? If not, nbd thats an easy find for me, got my giant FSM in the garage.

Gonna run to auto parts today for some of the cool tape to add to the harness, and I'll see if i can rent or buy a smoke tester from them.

And honestly, regarding the 3rd, when this first started a couple weeks ago now I was getting the same hesitation in hi/lo cdl on/off, kinda all around. But at one point stranded in a parking lot, 4Lo was moving me the best, not normal at all, just seemingly less hesitations.....

You obviously have a cruiser addiction and have to deal with vac leaks so I suggest picking up a smoke tester from Amazon. . Once you get this thing, you'll be checking everyone's rigs for leaks.

I believe you're correct with the hose sizes.

 

[MrErer]

Thanks for the recommendation @alia176 … ordered on Amazon and should be here in the am Now I can play with both trucks tomorrow (60 definitely has vac issues but it’s not my daily driver and priority right now)

I got the new EGR valve and modulator on tonight, and also wrapped up the main harness with the cool tape.…but, no change to stumbling engine, that would have been too easy hah.

Seems even a little worse tonight, I hadn’t started it in a week and a half but fired it up and died a couple times….gotta be vac leak somewhere right ?

vac leak smoke test tomorrow. Fuel pump if I can get to it.

 

[alia176]

Thanks for the recommendation @alia176 … ordered on Amazon and should be here in the am Now I can play with both trucks tomorrow (60 definitely has vac issues but it’s not my daily driver and priority right now)

I got the new EGR valve and modulator on tonight, and also wrapped up the main harness with the cool tape.…but, no change to stumbling engine, that would have been too easy hah.

Seems even a little worse tonight, I hadn’t started it in a week and a half but fired it up and died a couple times….gotta be vac leak somewhere right ?

vac leak smoke test tomorrow. Fuel pump if I can get to it.

Well vac leak is just one potential. Fuel pressure is another one that needs to be studied objectively. That's where a fuel pressure gauge inserted into the fuel system is very helpful.

Here's a simple writeup I did for installing a "test point" into our fuel system. Hope it'll help with your saga: Start here, may need to scroll up or down Needing some help with P0171 code - https://forum.ih8mud.com/threads/needing-some-help-with-p0171-code.1325962/post-15248557

When you get the smoke tester, I suggest introduce smoke into the intake by going through the large intake tube. The kit should come with a large disc thing that will allow you to perform the test in this manner. Let the smoke find its way through the TB (leave the throttle plate open somehow), and eventually through all the vac ports. Hopefully, you'll find some leaks!!!!

Another cool thing to try is to introduce smoke through the tailpipe using one of the smaller discs. This will help you find exhaust leaks!!!

 

[sogncab]

It is definitely backfiring.

When we're plugs and wires done last?

Did you check for broken wires on the harness?

My money is on a bad ground somewhere though.