Hi all, having some issues I hope you can help with. CEL came on a few months back...pulled the code, says egr valve. Its running perfect, and I haven't had time, so it hasn't been fixed yet. Now...two issues have popped up.

1. In the morning when its cold, there's a very strong exhaust smell when I first crank it (and a stronger than normal exhaust smell pretty much all the time). Seems like its running rich.

2. If I drive it, stop, and crank it back up once its hot, there is a strong gas smell for about 30 seconds, then it goes away.

Any idears? Maybe this is all related? Thanks for any help!

 

Fix the EGR valve, or delete it, and go from there ....

 

Alright, so I got an update regarding these issues. Drove it home from work, stopped at grocery store. Was inside ~10 mins. Came back out, started truck, had the usual fuel smell, and almost shut off (stumbling, etc.) Hasn't done this before. Cleared out in about 30 seconds and ran fine (fuel smell went away, as usual).

Went home, jumped FP and B+. Could hear hissing coming from pressure regulator, and I thought I could hear fuel leaking out somewhere and evaporating. Tried to feel around pulsation damper, but couldn't feel any wet spots.

I'm going to tear it apart tomorrow (its raining today; unfortunately, I gotta drive it).

Any other idears on what it could be? Why would the smell go away about 30 seconds after I start it? Hopefully I can track the source tomorrow and fix er.

On another note...I "tested" the EGR by applying vacuum and I could hear it opening and closing, so maybe its the temp. sensor. I'm not nearly as worried about the EGR and CEL right now...I'm pretty sure the fuel smell is unrelated.

 

I would keep a VERY CLOSE watch on this. You can end up burning your truck up....SERIOUSLY! I wouldn't even drive it until I found out where it was leaking...

...and you must have to INCREDIBLE hearing to "hear" fuel evaporating .....WOW!!

 

By hear I meant I thought I could hear it dripping somewhere, and I would assume it would be evaporating (motor still warm). Kinda hard to tell cause I can also hear it going through the regulator, which leads me to believe it is indeed leaking.

And yes, its getting fixed tonight. Well, parked tonight to be fixed tomorrow. And trust me, I know how big a deal a fuel leak is. However...it does it for about 30 seconds upon startup. Then...nothing. No smell whatsoever. I have walked all around the truck trying figure it out while it was running...nothing. I can't tell that any is coming out of the pulsation damper, which was my biggest concern since its right over the crossover pipe.

I'm thinking maybe its an injector o-ring? Leaks for a brief instant when starting then seals itself? Also...it doesn't do it in the morning when its cold. Only after the motor has been hot and cut off then cranked again.

 

Alright, so I took er apart this morning. Got down to the fuel rail, popped the cap off of the pulsation modulator or whatever its called (pass. side, firewall). I then heard tink tink tink. So the screw was obviously out and fell. Lo and behold I found it.

Its a tiny brass screw with an o-ring. Sound right? I'm stumped because there are no signs of fuel leaking from there, though I'm certain that has to be what it is. So my question is can I remove the thing, reinstall the screw (with some LOCTITE!), and be on my way? I don't want to spend $130 on a new one...

Thanks!

 

Alright so now I'm not so sure the pulsation damper is actually bad. There are no signs of any fuel leaking out of it, only the screw was backed out, which, from what I'm reading, serves only to indicate fuel pressure is present, and is NOT a sealing screw. So scratch that.

As I was taking the plenum off, I noticed some fuel ran out of the vacuum line attached to the fuel pressure regulator. This would indicate it is bad, correct? Would it also cause a raw fuel smell when hot-starting, as well as result in extra cranking require to start when the motor is hot?

Could use some help here before I go replacing things. Thanks.

 

Are you talking the small vacuum line attached to the FPR? If there's fuel in that, then there is your problem. THere's a larger hose on the FPR that will have fuel in it; that one is ok (points toward the front of the truck, it's fuel hose size).

 

Have you tried to pressurize the fuel system? That will show you where your leak is. You have to jump a some connectors in the diag block to get the fuel pump to run. I forget what they are named, but it is the back two corners. Be sure to block off the return fuel line from the fpr.
I agree that if you have fuel coming out in the vacuum line, then the fpr is your problem. But to be sure, pressure up the system first. Leave that vacuum hose disconnected, and if you have fuel coming out of it then replace the fpr.

 

FB and B+, and yes I did that. There was a hissing sound in the regulator.

The fuel was in the small vacuum line, not the return line, so I think that's the problem...

 

No fuel in the return line at all?? It should always have fuel running through it, well unless the fpr is totally stuck closed.

 

Sorry, don't know why I said that. Wasn't thinking. Yes it was in the return line too.

 

Similar problems with my 91 PU 3.0... Subscribed.

 

Fuel in the FPR vacuum line, FPR is bad, replace it.

 

Just as a small note I would like to mention that I think 3.0's do tend to smell a bit rich all the time, I think it's just the way they are, everyone I've ever been around has been like it... lol

Maybe I'll actually put a cat back in mine..

 

Sounds like you have the famous fuel Damper issue on the 3vz models. The little screw falls out when the rings inside fail. You can by a new OEM replacement DENSO part from Kragen for around $70. The new ones don't have the plastic or screw on them, instead they have a metal top pressed on to enclose the housing to prevent from fuel leaks. The guy that posted above said be careful about your truck burning, worse case scenario the fuel could drip out and catch your engine on fire. You can google tons of images of the damper burning up toyotas and see it has happened often. Some people wonder why toyota never ran a recall on the damper. While you have the plenum off be careful not to bump your BMV (bi-metallic valve) its a plastic regulator that has tubing connecting to your charcoal canister, the plastic nipple connectors can become very brittle and break. Since you would have your plenum off, it would be a smart idea to replace your PCV. My friend who is a mechanic for toyota was saying the damper often goes out because the PCV is going out to, and if you replace the damper usually you will have more issues with the PCV. This was true in my situation, after I replaced the damper that regulated the fuel pressure, my truck started to run a little hotter and leaked oil from the valve covers. That was 4k miles ago when I replaced the PCV and fixed the gaskets, since then everything runs great. Some food for thought for you though.