Thread: N/A Gas Mileage Help

I was smelling fuel in the ****pit as well and couldn't figure out where it was from, until one day when I parked on a hill with a full tank of gas. One new gas tank later and my mpgs are back in the 30's! It had rusted out around the breather hose that goes up to the fuel filler cap. As your car is in Texas, I doubt you'll have as big of a rust issue, but who knows, so I'll mention it. Keep us posted if you find the source.

i agree with ben alot of fuel or dumping fuel and fuel smell can be atributed to the CTS going out, when they are bad they dont have a leanier reading so it always thinks the engine is cold which results in the car constantly being in closed loop for warm up which is where the car runs slightly richer for warm up, or its bad and reading a hotter temp and the car is dumping fuel to compinsate for the cts reading thinking the car is overheating. 1 of the 2 but maybe neiter

I think you guys are right on the money. The other day I was jumping my gf's dead battery, and the coolant began to overflow a bit after about 2 min of constantly revving at about 3k rpm. I shut the car off and let it cool for about 5 min, and didn't have any issues from there. Now I just have to figure out where it is. I'll keep you posted.

If that doesn't fix it, I'll check the O2 sensor next.

Just a quick update. First gas tank after alignment ran just above 28 mpg doing the same driving as when I got 22 mpg last week, only with a bit more bias towards highway this time. I'm almost halfway through the next tank, I'll update my findings then, in case it's a fluke or I did something wrong. I re-cleaned my MAF and the gas smell in-cabin has gone down considerably. However, I will still replace the ECTS and check the O2 sensor on Wednesday.

Okay, I checked the O2 sensor via the ECU, and it's blinking more than 5 times (actually about 9-10 times) every ten seconds at 2000 rpms under no load. Damn. FSM says that means it's bad, if I'm not mistaken. I also changed out the Crank Angle Sensor and that CEL is gone now. I still have the 35 one (Exhaust Gas Temp Sensor), but I've been on the lookout for a 100k or 68k ohm resistor to put that to rest. At any rate, I bought a new ECTS and am waiting for a day off to have the car completely cold before I try to replace it, for fear that I'll scald myself. The O2 sensor will have to wait till the checks from the new job start coming in.

Also, I discovered a small leak from the clamp holding on the rubber hose between the fuel filter and the hard fuel lines running back to the tank. I tightened the clamp and that fixed that. I think this obviously contributed to the raw fuel smell but not entirely, as, even after I fixed the leak, the idle is not as rock solid as it could be. The quest continues. The car bogs wicked bad in second. I pull out the clutch at 1800 RPM, the RPMs drop to about 800, and pedal to the floor it will still ever so slowly climb in engine speed. It doesn't do this in first.

Jumped the gun and got the O2 sensor and replaced it. Car's got a lot more get up and go now, but I still haven't replaced the ECTS as it's in an annoyingly difficult spot to get a wrench to it, being that it's next to the oil filter, under the arc of the #1 highport intake runner, and next to another sensor or other on the other side of it. I'm thinking I'll try to get it when I change the oil, as I think I'm a little overdue for it. Any tips would be great.

Still getting the smell inside the cabin, no leaks yet from the fuel hose I tightened the clamp on. I'm hoping changing the ECTS will fix this. I STILL haven't had a chance to freaking solder that reground (apartment life sucks), so I suspect that my crappy MAF still has something to do with it. If the ECTS and MAF reground don't work, then I'll try replacing the MAF, and if that doesn't work, then I'll check those injector rings.

Still have a CEL, neither the 100k nor the 68-ohm resistors did...anything. I'll recheck the codes when I get more time. Right now brakes are giving me hell.

Gas smell did go away after all. Never did reground the MAF. Still have that CEL.

Finally fixed the brakes, but the gas smell came back. I also finally replaced the ECTS. Discovered the gas smell is from either the return or feed line by the gas tank, I'm replacing both. Hopefully with that all put together, the gas smell will be gone for good. I'm still running rich as sin though. Is there a way to adjust the a/f mixture mechanically? My old '88 Chevy had a screw I could play with on the TB to do this.

I have been having problems with a gas smell as well. I have replaced both return and feed lines, as well as inspecting the two tubes going to the gas cap. But still, when I have the driver's side window or sunroof open, I get the smell. I'm 95% sure it is that the o-ring under the plate for the fuel pump is on incorrectly. They are about $10 from GregV, it might be worth your time to order one and swap it. No idea about how to mechanically adjust the a/f, sorry.

I'm sure about the lines, I had the mechanic put it on a lift, and poking at them one of them spat out fuel through a small crack, but when I went to the dealer, I wasn't sure which was which, so I ordered both. It might not be a bad idea to order that o-ring while I'm at it, though. I wonder if it'll get here before Thanksgiving.