New thread on an 02 with a 3191

Yeah, I know, dummy code, but that's the only one TorquePro pulls. This is the car I got in Minnesota, drove to TX, then CA, then back to TX. First day, I drove a couple hundred miles, no problem. Next morning, in the 20s overnight, it throws a 1437. Knowing MN cars get some rust, I assumed the exhaust vent was stuck open. Car seemed to run fine, and we headed south.

Drove fine all those 5k miles until 10 miles from home and all went to heck. Was throwing misfire codes for all cylinders and P0440, P0441, and P0446 codes. We came back with a trailer and got it home. I ordered a new cat, ox sensor, and vacuum reservoir intending to swap out the OEM cat and hack the vacuum line.

While I'm waiting for the parts, occurs to me that the OEM may already be gone. I check and sure enough, it's already been replaced by an aftermarket cat. However, they didn't hack the vacuum line. It's just hanging open under the car. So, I've assumed that's the reason for the original 1437 code. My parts came in and I was hoping that simply hacking the vacuum line would restore equilibrium and the ECM would start firing the ICE correctly. I did that today.

I cleared all the codes, installed the vacuum reservoir, and restarted. Inverter kicks just fine, but the ICE did nothing the first try. Engine died, Ready went out, and the triangle and exclamation point car, and CEL lit up. Over a few more tries, the ICE would start, but stumble badly and die in 5-10 seconds. Deal is, all I get is the 3191.

Of course, 3191 can be many things. Hoping someone has some ideas, based on that history, that might narrow the diagnosis. For example, could driving all those miles with the 1437 have blown out the ox sensor or that cheap aftermarket cat? I'm not getting those P04XX codes now - did the vacuum hack fix that, or maybe just because the ICE hasn't started/run long enough to set them? Anything about those 4xx codes that might suggest an issue?

I doubt the worst case scenarios - engine isn't locked up, out of oil, inverter pump not working, etc. I'm assuming that getting misfire codes on all 4 cylinders suggests the problem isn't with plugs/coils/injectors, that it's more likely an ECM issue not telling the injectors to fire/fuel/etc. So which sensor could be guiding the ECM to assume issues and defuel?

 

Hmm, lost you a bit there, TB. The crankshaft is turning complete revolutions. The service manual gives a fairly finite list of possible causes when there's only a 3191 and no other codes - fuel pressure, MAF sensor, air induction issues, crank/cam sensors, the ECM. Pretty high-level stuff that typically doesn't fail while driving 60mph down the highway.

I just hesitate going down that path - none of the suggestions seem like the obvious answer, or an answer at all, IMHO, except maybe fuel pressure. But, I don't really trust TorquePro to pull all the codes or, again, maybe it's not run long enough to throw some codes?

 

OK, reset. User error.

First thing I did today was to try starting it and then shifting to N. It stumbled a little bit longer, and threw the 3190 code instead of the 3191, but otherwise no better. I pulled a spark plug and it looked normal. I loosened the fuel rail and lifted it up, put didn't pull any injectors out of the rail - I had such an issue getting those o-rings back in last time that I didn't want to mess with them. Still, there was no signs of fuel. I turned the key on to make the fuel pump run and nothing happened. I thought the fuel pressure might push an injector out of the rail, but it was all dry.

But maybe not thinking correctly, I assumed that meant I wasn't getting fuel pressure. Now I'm thinking I needed to pull an injector from the rail, then I would hear the escaping fuel pressure and see fuel come out. And, with the key on a few seconds, fuel would come out the rail. I understand that seeing fuel wouldn't mean I have enough pressure, it's not an accurate measurement, but if nothing comes out, I would know the problem. If I had fuel pressure, would that be enough at key on to push an injector out of the rail?

Anyway, went back to my manual and started from scratch, with those 044X codes, and quickly figured out that they are about emissions from the gas tank, not the exhaust. Stupid me. My assumption that those were the result of driving so many miles with the 1437 (unplugged exhaust vacuum line) was wrong. The diagnostic process for those codes stresses checking the gas cap and lines for leaks and obstructions, which I hadn't done, but I did recall that the cap felt kind of funky when I'd filled up. So, I checked the car, and the fill neck is funky. Moves all around within its rubber grommet I thought it was completely broken loose from the filler neck, until checking my other car. Now, I'm thinking the metal part the cap screws into isn't attached to the metal fill neck at all. It's just suspended inside the rubber grommet. The grommet is the sealing surface and physical connection between the body and the filler neck. Still, the cap moves around so much more in this car, that it seems like it should be a problem.

I can't see how to take the filler neck apart, or if it does come apart. My bootleg manual has the pages all out of order and I haven't found anything about removal/install of the filler neck/grommet.

For y'all: First, I'm not sure I have no fuel pressure, but could a leaky fuel neck grommet, bad enough to throw 044x codes, prevent the fuel pump from pressurizing/whatever the tank and make the engine lose fuel pressure? Could that be the cause of my no-starts and misfiring?

Second, anyone ever replace that neck grommet? Is it even broke? Is it more likely that its the grommet leaking and not the gas cap in its floating filler neck?

The last possibility I can come up with is water - either in the gas or in the spark plugs or fuse box. This problem happened after driving in rain for 50-100 miles on the interstate. I had never even opened the hood on this car before driving it thousands of miles. When I got it home and did, the fuse box covers were all lose, and the smaller center relay box's cover wasn't even on it. So, maybe water came in the cowl and got in there? So, I need to check my fuel pump relays to make sure the pump is even getting juice.

Any other ideas appreciated.

 

Thank you, sir. I'm not good at searching, apparently, lol. I've seen you mention a post that details repairing/cleaning the PS torque sensors, and haven't found it. Another time you mention a vid on getting those darn injector o-rings into the fuel rail. Dang, wish I knew that trick before wasting $80 on o-rings/grommets. Haven't found it either, lol. And I searched around for info about the fuel neck and haven't found much, but you say it's there, and I believe you.

Know any good keywords? NP, you've motivated me to keep searching.

 

UPDATE, although no resolution. Pretty sure my problems with this car involve the gas tank neck. On further inspection, the filler neck is completely rusted through on the bottom side. Have to think that would cause sealing issues for the gas cap and throw those 044x codes, but I'm also thinking I got a water in the tank - the car ran fine for 5000 miles across America, and then started misfiring after driving in rain for an hour.

The bootleg service manual I got is missing pages, or I haven't found them, on how to remove/replace the filler tube. Right now, the part that the cap screws into is loose and moves all around. Looking down the hole, I can see the tube staying in place while I move the top. Somehow they've separated or maybe rusted in two? The dealer showed a parts breakdown that has the filler tube as two separate PNs, one for the tube, but can't tell if the second is just the cap, or just the section that the cap screws into, that maybe includes the rubber grommet that goes all around the body rim.

Anyway, hard to describe, but hoping someone has taken this apart, or has pages from a good service manual, anything that tells me what I'm trying to replace and how to get it off. From the trunk, it's all behind sheet metal. Not sure it the tank has to come off to bet to it from the bottom.

I bought another parts car and have a good tank, but maybe I only need the replace the tube. IDK.

 

OK, y'all made me do it. All you had to do is post PDFs with pics and detailed instructions on how to replace this filler neck. But nooooo. I'd already tried to see how to do it from the trunk, and through the filler hole, but could see nothing. Now, because none of you would do it for me, I had to bend over - at my age! I had to reach my hand up under the wheel well and feel around. Everything is right there for any idiot to see, and yet, y'all expected me to find it. I think I can handle it from here.

 

I haven't done it yet. Trying to decide which car to part out.

 

I put this one aside for a bit but it's now top of the queue. I've tried water-removers in the gas tank, and swapped in a good filler neck, it still didn't start. Since I had spare gas tanks, I'm going to swap one in, along with known-good injectors, plugs and coils, then clean the MAF and throttle body and give it another try.

It's easy to replace the filler neck, and to drain the gas tank. The filler neck ends in a typical rubber hose attached to the tank with just a hose clamp. Just pull it off and stick a siphon hose down into the tank.

The tank is easy to remove as well - as long as you can get the car high enough in the air to pull it out from underneath. Just four main bolts and a handful of small hoses and connectors to detach. Easily taken off in an hour. My next step is to install the replacement, so I'll let y'all know if that fixes the problem.

And, yeah, everything Chap says about the 3191.

I do have another spare gas tank if anyone needs one, although I've not taken it off the car yet.

 

Dang, installing the gas tank is a whole lot harder than taking it out. Just because of the weight, and because I'm lying on the ground, and because I'm obviously a weak, lame kinda guy. Not enough arm strength at this angle, but if I could get under it, to lift with my back/legs, no problem. Coming out, that weight works for you to make it fall down. If the car was up on a lift, much easier.

Could do it with a helper, but don't have anyone. Now, it looks like I'm going to have to remove the entire exhaust pipe, from the exhaust manifold back, because that's the part you have to finangle the tank around to get it back up to the frame. It'll be a straight lift without the exhaust in the way.

 

Well, I managed without taking the pipe off, but a real PITA. I had the pipe tied up out of the way, trying to get either the front or back sides (with the bolts) up first. Either couldn't then get the pipe back down or the tank past the rear axle. Finally, tied the pipe back and DOWN, then came in with the tank from the passenger side. Back lip over the pipe, then tank turned to get the driver-side back lip over the axle, then straighten out and work the passenger side over the axle. I didn't take pics, and you wouldn't want to see them if I did. I recommend that you find a lift for the car or take the exhaust down.

The flange bolts at the rear were rusted, so I just cut them. I have another muffler pipe. I also cut the rubber hangers. Those at the resonator are standard auto parts store compatible. One at the muffler has a 90d turn. I didn't destroy it - cut mostly through the top hole and then broke the rest. I think I'm going to try to glue it back together. Reddit suggested the black glue tire shops use. Anyone every glue rubber to rubber?

 

Otherwise, today's the big day. I've replaced the tank and swapped in known-good plugs, coils, and injectors. Recall, it would start and sputter for several seconds before dying, even after replacing the rusted fuel neck. Before the rain, it ran great. Got my fingers crossed.

 

Woohoo! Success. I put some gas in it, let the fuel pump cycle at key ON three times, and it started up. Sputtered for about 5 seconds, then smoothed and idled to WOT and a full battery charge. I swapped over a door and fender to this car of a different color or it'd be ready to go. I think, instead, I'm going to take a door/fender off another silver car I have. That car has a dented quarter panel and bad clear coat on the roof/hood/trunk lid, so it needs to be painted anyway.