Rough Idle after Vacuum line replacement (1 Viewer)

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Maybe you had a vac leak before that the ECU compinsated for and now you fixed a leak and the ECU needs time to catch up. Just a guess. Also any time work is done/completed your immagination will make things up and you will hear, see and feel things that where always there. I do that all the time. Drive myself crazy over nothing. I would put some high test gas, fuel system cleaner and drive it and see if it returns to normal before chasing your tail for nothing.

I wondered about the "learning" situation by the ecu? I'm gonna give it a couple of days and see if it gets better. I can tell you that many of the tubing fits very loosely. So much so, that it can be easily knocked off of the fitting with a glancing touch. Too loose in my opinion.
 
Also having rough idle problem with my 3FE LC80

Hi Aggiesm, Have you considered looking into the Air Flow Meter (AFM) sensor unit of your engine intake? I seem to have found the culprit in mine and there seem to be a loose in the connection. Attached is the picture of what I found.

9288130319

9290902498



Once I put this together, will observe what happens and give an update.

Here's a link on a good write-up on how this unit should be opened and checked, with pictures: https://forum.ih8mud.com/80-series-tech/301606-3-fe-vaf-meter-woes-lesson-learned-hard-way-2.html

Hope this might be of help to you, too.

Thanks!
 
I wondered about the "learning" situation by the ecu? I'm gonna give it a couple of days and see if it gets better. I can tell you that many of the tubing fits very loosely. So much so, that it can be easily knocked off of the fitting with a glancing touch. Too loose in my opinion.

You're over thinking this. If the vac tubing you used is so loose that it can easily be pulled off, then you have found your problem. You created a vacuum leak. The system needs to be well sealed.

Most likely the tubing you purchased was not a metric size. The tubing should be 3mm ID for all the small stuff. I bought mine at McMaster, part number 9355T11.

 
Do it once and do it right. Part number 90999-92003 is about 2ft of oem line for under $2. I bought 10 of those and had enough to do all the lines on my FJ60 except for the really long ones. You'll be fine on a 3FE.
 
Thanks all. I'm with Jon on this one. I'm convinced I just have a series of tiny vacuum leaks that has cumulatively depleted the system of all vacuum. I'm waiting on my local dealership to let me know if they can sell me a 25' roll of the vacuum line. They said that its usually only for the shop??? What? Anyway, if not...I'll order the McMaster probably.

Anyway, one more question. As I was inspecting the system, I was trying to clean out some of the hard lines and most were fine, but there were 2-3 that were so clogged that I couldn't get a wire into them at first. I eventually sprayed a little carb cleaner and kept working the wire to "break up" the gunk, but I still wasn't able to get all the way into the hard line before it started to make twists and turns. Wondering if there is a good solvent that I could spray in there to break up the funk?
 
I used a teeny drill bit to create a hole. Once you get through the clog it will break up easily.

Thanks for the tip. I was using a single strand 16g wire and it seemed to work, but I think something more rigid would help.:cheers:
 
You're over thinking this. If the vac tubing you used is so loose that it can easily be pulled off, then you have found your problem. You created a vacuum leak. The system needs to be well sealed.

Most likely the tubing you purchased was not a metric size. The tubing should be 3mm ID for all the small stuff. I bought mine at McMaster, part number 9355T11.

Hey Jon, when I search McMaster for that PN, it lists a few different hoses. Can you be more specific on which hose you use? Obviously it's 3mm, but there are a few that have metric sizes. I'm also assuming its black, not clear, but there are choices there too.

Here is the link. http://www.mcmaster.com/#catalog/119/141/=nmvjgd
 
Ended up ordering 25' for the 3mm black standard hose. I'll report back when I get it installed. BTW, it was $13.50 shipped! Called the dealer today and for 1 x 10' section the MSRP was $85ish. Crazy...
 
Ended up ordering 25' for the 3mm black standard hose. I'll report back when I get it installed. BTW, it was $13.50 shipped! Called the dealer today and for 1 x 10' section the MSRP was $85ish. Crazy...

Nice... That was from McMaster Carr?
 
When I enter the part number in the search window, it comes up with the part number and description on the left hand side.

9355T11
(Same as 9355T1)Metric Extra-Flexible Nylon Tubing 3mm ID, 5mm OD, 1mm Wall Thk, Opaque Black
 
When I enter the part number in the search window, it comes up with the part number and description on the left hand side.

9355T11
(Same as 9355T1)Metric Extra-Flexible Nylon Tubing 3mm ID, 5mm OD, 1mm Wall Thk, Opaque Black

Good, that's what I got. Crossing fingers that it'll work!
 
Yep. They are a good company and their products are usually pretty high quality.

Cool. Yeah, I've had to get a few odds and ends from them...

I was going to say, I stopped by NAPA on my way home yesterday to pick up the "smog pump delete belt" and they had smaller vacuum line, .09 inches, or nearly 2.3mm... If worse came to worst, that would certainly grab onto the vacuum hard lines...
 
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Cool. Yeah, I've had to get a few odds and ends from them...

I was going to say, I stopped by NAPA on my way home yesterday to pick up the "smog pump delete belt" and they had smaller vacuum line, .09 inches, or nearly 2.3mm... If worse came to worst, that would certainly grab onto the vacuum hard lines...

Yeah, I thought about that, but I've heard that the 3mm is pretty tight, so lanky thing smaller would be a bugger.

Aaron, will you be able to make it to Jim's place on Friday for the radiator party?
 
fwiw the 3.5mm silicone i used is pretty snug. When i was doing the VSVs under the throttle body on my 1fz i had to dampen some of the nipples to get the stuff pushed on.
 
Yeah, I thought about that, but I've heard that the 3mm is pretty tight, so lanky thing smaller would be a bugger.

Aaron, will you be able to make it to Jim's place on Friday for the radiator party?

Right now, I don't think so... But he's gonna keep me updated on your progress, so if it runs late, I might show up.

There's also supposed to be a U-Joint party at my place this weekend... :D
 
Right now, I don't think so... But he's gonna keep me updated on your progress, so if it runs late, I might show up.

There's also supposed to be a U-Joint party at my place this weekend... :D

Man, there never seems to be enough time for fun wrenching! I wish I could make the U Joint party after my half a** attempt last weekend. Ive got a full weekend planned with the family, but Let me know what you find out and any tips for sure.
 
OK, Got the vacuum line from McMaster Carr and I don't know if I ordered the wrong thing or what????

I tried to fit a small section onto one of the hard lines and this stuff is so stiff and the ID is so small (3mm) that I really had to wrestle to get it on at all. There is no way that its going to fit good enough in some areas. Not to mention its really pretty stiff, not flexible rubber like the other vacuum hoses I've used. Its more rigid. Although it is flexible it doesn't stretch to fit.

JonHeld, and suggestions? I ordered what I thought was your recommendation, but doesn't seem to be the correct style.

I just want some freaking vacuum hose. Who knew it would be this hard???:bang:
 
I picked some up at our local Oreilley's Auto. They had a shelf in back with several spools of rubber line, and they just let me pick the one the I wanted, and then cut it for me.....
OK, Got the vacuum line from McMaster Carr and I don't know if I ordered the wrong thing or what????

I tried to fit a small section onto one of the hard lines and this stuff is so stiff and the ID is so small (3mm) that I really had to wrestle to get it on at all. There is no way that its going to fit good enough in some areas. Not to mention its really pretty stiff, not flexible rubber like the other vacuum hoses I've used. Its more rigid. Although it is flexible it doesn't stretch to fit.

JonHeld, and suggestions? I ordered what I thought was your recommendation, but doesn't seem to be the correct style.

I just want some freaking vacuum hose. Who knew it would be this hard???:bang:
 

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