PlotPoint

In case it's related...my car was in the shop a few weeks ago and the mechanic said the car had a minor valve gasket leak so he tightened things up. I noticed a fresh fuel smell last weekend...not the first time that has happened, but it was intermittent so wasn't too concerned. The fresh fuel odor was stronger yesterday and again this morning, so checked under the hood I can see spattering around a large bolt (not sure if that is the term -- plug?) which is wet with fuel. It is dry until I start the car and then I can see seepage around it and it's fuel. The seepage continues after the car is turned off (for how long I do not know).

Attached a pic so you can see where it is...you can't actually see the bolt but it's at the opposite end and underneath the hose that is directly above/next to the lettering "CAM 32". Sticks up about 1.5 Inches. It's wet, and a small pipe/hose leading off the bolt (less than 1/2" in diameter) is also wet from fuel seepage.

You can see spattering in the pic below...it's is on the slats towards the right under the pipe/hose that is above "cam 32".

dicer

Can't tell could be a fuel line to injector. Just don't be driving it like that. With it cold run it for a minute or so and look for the leak. Have a water hose handy. You don't want to spray dry chemical in there it will be impossible to clean out and will corrode everything you can't clean it off of.

PlotPoint

I had it towed.

On a cold start up (this morning) it was not gushing by any means, but a rapid drip all the same. The top part that is sticking out (vertically) is about 1.5" high and it's round. It's possible the fuel was shooting up and hitting the pipe directly above it and dropping back down too (making it look like a drip). I just don't know.

Once I realized that it was fuel that was leaking, I turned it off ASAP, wiped off the bolt/post? and watched what happened. Fuel continued to seep over the top of it even after the car was turned off. Emphasis on a slow seep. However, nothing was coming from the line/pipe directly above it. I know the seepage eventually stops because this morning when I looked at it before I started the car, that bolt/part was dry.

I did a Chevron Techron treatment the tank before last and followed their instructions exactly...adding the bottle to a near empty tank and then filling it up with max of 12 gallons (this was a small bottle). Now wondering if that caused this. It may have just exacerbated an ongoing problem, because I remember that off and on during the summer I would smell fuel, and had some concerns about that (even posted about it one of the forums).

This is the first time (after smelling fuel) that I looked into it myself -- it was immediately obvious what area was involved, if not the exact part. Just curious why any one of the crack mechanics who have looked at my car in the past few months didn't raise the issue.

An interesting side note -- my smog tests have gotten progressively worse on the last two smog checks, whereas the readings were always well within limits before. It's to the point where the car is just barely passing due to high NO2. Just read that even at 8 to 10 percent restriction in a fuel injector can result in a lean fuel mixture (which is one of the causes of high NO2). Would be great if replacing that fixes both issues!

Koping against hope that it's relatively inexpensive to fix.

dicer

What year car? If its a hose replace all of them. And give the rest of us a heads up on what it was, old hoses get crusty.

PlotPoint

'94. It was the fuel pressure regulator. It's being replaced tomorrow. Oh, and they said it isn't likely that replacing that part will help with the high NOX smog readings.

I am paying $207 (?) for the part (assuming it's OEM) and about an hour's worth of labor. After getting their estimate, I immediately called another Lexus shop that has an online parts business (where I have gotten good prices before) to see what they were asking for the same part. It was almost identical to the shop's quote, so I approved the work. Later on in the day, I googled the part, and the first one that popped up cost $32 on partsgeek. Am assuming it's not OEM. I know OEM parts are always a good idea, but given how old this car is, I really question whether it's worth it to use OEM. Not like I have a choice (I doubt the shop would install anything else -- they are Lexus indie specialists). Anyway, yes, the part is available at a wide range of prices.

dicer

Just because its oem doesn't always mean its made at a good place. Simple parts like that I wouldn't hesitate to go to Oreillys or NAPA for it. And its a simple DIY deal too. If rail pressure is way down along with egr problems that could cause the high Nox. It would have been better to spend the $32, and do the install and have the shop deal with the emissions related problem. So do you get a service waver in that state? Here its $150 I think.

djamps

Fuel pressure regulator is key to emissions. Any change in pressure will affect the air fuel mixture. I'm surprised they told you a failing fuel pressure regulator is an unlikely cause. If it were me I'd hook up a scan tool and look at the short and long term trims. But with a pre-ODBII car it might not be so simple.

UNCNOR

iTrader: (1)

What is a service waiver?

dicer

Here if your car fails emissions, you have to spend at least 150 or it may now be 200 to fix it by a certified emissions tech to get a waiver, you need that if it doesn't pass the emissions test after the work. So even if its been worked on and still doesn't pass you can pay to have it pass. If you spend 1000 doing it yourself that does not count towards the waiver, unless you are an emissions certified tech.

PlotPoint

All, thanks for all the responses -- very helpful. My car is back and "fixed" with a new fuel damper regulator (not the same as a fuel pressure regulator which turned out not to be the problem) and it now has a very noticeable knocking sound in the engine bay. And ideas? And when I cranked it over to drive it out of the shop it ran really rough. Didn't last long (and I was told it was because it was cold --, I have started my car many times cold and never heard that. Could an aftermarket fuel dampener cause this? It appears to be a good quality aftermarket part. It was NOT doing this when I took it into the shop. Can provide more detail if you need to help figure out how I went from a normal sounding engine to this in a matter of two days. Tx. Also is it typical to do a 100% markup is on a part? I think I know the answer to that, since I paid double what it sells for online.

PlotPoint

The guy I spoke with was a service writer, not a mechanic. He wasn't sure. Turns out it was the fuel damper regulator that they needed to replace. Will that also impact emissions? If so I might get a pre-check smog test to see whether fixing that made an improvements in the NOX reading.

PlotPoint

Yet another update! I am not sure if this is worse news or just what. Apparently I drove home from the mechanic's shop in super heavy traffic some ten miles with the gas cap off and the tank lid open. Do I think I "accidentally" popped the gas cap off? No. Even if I had accidentally pulled the lever to pop the gas tank lid, the gas cap would not have popped off on its own. No way. Miraculously, it was wedged somehow in the lid and had not fallen off. At fill-up, when I replace the gas cap, I turn it to the right at least three clicks. After I put the cap back on the engine knocking noise dropped dramatically, but it's still there. I will see if it sounds better tomorrow I hope I did not do any damage by driving it like that. I am assuming some air got in there.

dicer

Engine knocking noise and fuel cap. Nothing with the fuel cap is going to cause the engine to knock or not knock. Fuel grade can cause it though. So is the knock combustion or a mechanical noise?

Yamae

As long as the knock sensors and the ECU are working OK, you seldom have a knocking problem even you use the regular gas.

I'd check the signal from knock sensors and the ECU first.

PlotPoint

It sounds mechanical to me, but I cannot say for sure. The knocking noise dropped by at least a third (and maybe even by half) when I replaced the fuel cap, but the noise is still very noticeable. I read that the cap is important because it pressurizes the fuel system. That's why you hear that hissing sound when you remove it. I may be on to something. I googled "replacing fuel dampener" and "engine knocking' (or something like that), and found a thread where others driving different make/model of car had experienced that. One guy said the culprit was a brittle cracked fuel line leading off the fuel dampener. It definitely is related because my car's engine was not knocking like this when I took it in for repair. I should check the oil too.