2011-06-01	384	10.333	$3.789	37.16	"This is the first tank of fuel I used. All tires inflated to 40psi (44psi sidewall max, door placard specifies 30psi-front/29psi-rear). I drive with headlights on. I also travel with 85-90 pounds of gear in the trunk (I need it for work)."
2011-06-10	343	10.16	$3.719	33.76	"The car spent the day at the shop for service (including repairing/recharging the AC and replacing leaking fuel lines), so who knows how much fuel was lost?"
2011-06-20	363.2	8.821	$3.719	41.17	"I dropped max highway speed from 66mph to 57mph. I now set the cruise control to maintain a minimum of 55mph uphill. At 55-57mph, it's fast enough to not get totally run over in the slow lane. It's also a decent speed to allow cars to merge onto the highway with little bother."
2011-06-27	393.7	9.267	$3.679	42.48	"Tires were inflated to 44psi. It doesn't ride as nicely as it did before, but it seems to have better fuel efficiency."
2011-07-19	413.2	9.84	$3.739	41.99	"This tank had an upper grille block in place."
2011-07-25	429.4	9.644	$3.739	44.53	"This tank had no power steering. Also, I removed the upper grille block after a few hundred miles because the temp gauge was skyrocketing with the hot weather (it didn't seem to be helpful, anyway)."
2011-08-01	474.6	10.589	$3.739	44.82	"I've converted the front signal lights to daytime running lights, and I now use them instead of running with headlights on during the day."
2011-08-05	391.9	9.18	$3.699	42.69	"I couldn't use my customary pump to fill up. According to my ScanGauge, this pump filled more than the other would have filled."
2011-08-15	404.9	9.3	$3.639	43.54	"Back to my usual pump. ScanGauge confirmed that it fills less than the pump I used last time. Rain has had a negative impact on my mileage. I'm still hoping to hit 45 mpg before my new carbon fiber hood arrives."
2011-08-22	418.6	9.23	$3.599	45.35	"I finally hit 45 mpg!"
2011-08-30	446.7	10.355	$3.599	43.14	""
2011-09-01	409.8	9.141	$3.659	44.83	"I've got a carbon fiber hood now. It's lightened the steering noticeably. Hopefully, we'll see a consistent increase in fuel efficiency."
2011-09-14	443.9	10.717	$3.639	41.42	"At 61.5% of this tank's mileage, I installed LEDs to replace the front signal lights (which have been converted to DRLs). I replaced the flasher relay with one designed for LEDs. I expect mpg to rebound with the next fill-up since ScanGaugeII indicated that I filled up with more fuel than what was expected."
2011-09-21	294.6	7.004	$3.599	42.06	""
2011-09-29	436.9	10.042	$3.559	43.51	""
2011-10-06	419.7	10.373	$3.519	40.46	"Rain and cold weather have been taking their toll..."
2011-10-19	395.5	10.484	$3.479	37.72	"Here's confirmation that speed kills mpg. I made two trips with a max speed of 65mph (instead of 57mph), and my fuel efficiency dropped to a near-record low."
2011-10-27	379.2	9.407	$4.439	40.31	"I've replaced now the third brake light, the brake/tail lights, and the plate lights with LEDs. The only non-LED external lights are the headlights and the reverse lights. I've disconnected the DRLs as they stopped functioning as soon as I replaced the tail lights. Cold and rain continue to drain fuel efficiency. Unfortunately, I don't expect it will improve again until spring. Top speed down to 57mph again..."
2011-11-02	307.2	8.034	$3.419	38.24	"Holy crazy October weather, Batman!"
2011-11-04	350.9	8.408	$3.419	41.73	""
2011-11-08	300.8	7.895	$3.399	38.1	""
2011-11-11	443.5	10.392	$3.399	42.68	""
2011-11-15	429.8	10.562	$3.399	40.69	""
2011-11-21	407	9.994	$3.399	40.72	""
2011-12-02	439.2	10.869	$3.359	40.41	""
2011-12-07	308.8	7.829	$3.339	39.44	"Tried (unsuccessfully) to jump start the Monte Carlo..."
2011-12-08	413.7	10.188	$3.319	40.61	""
2011-12-15	429.1	10.828	$3.299	39.63	""
2012-01-02	355.6	10.088	$3.239	35.25	"Cold weather stinks. Gotta check tire pressures more frequently."
2012-01-05	424.8	10.958	$3.359	38.77	""
2012-01-10	369.2	9.052	$3.339	40.79	""
2012-01-17	416	11.115	$3.339	37.43	""
2012-01-18	357.9	8.848	$3.439	40.45	""
2012-02-01	448.4	11.202	$3.519	40.03	""
2012-02-08	427.1	11.326	$3.539	37.71	""
2012-02-15	415.4	10.246	$3.559	40.54	""
2012-02-27	424.3	10.528	$3.639	40.3	""
2012-03-02	428.2	10.852	$3.699	39.46	""
2012-03-06	334.4	8.215	$3.659	40.71	""
2012-03-09	435.9	10.439	$3.649	41.76	""
2012-03-15	370.2	9.037	$3.739	40.96	"I've installed another upper grille block. My cooling issue was elsewhere."
2012-03-21	447	10.71	$3.799	41.74	""
2012-03-29	441	10.711	$3.759	41.17	""
2012-04-03	342.3	8.472	$3.765	40.4	""
2012-04-09	429.2	10.319	$3.839	41.59	""
2012-04-12	447.4	10.72	$3.839	41.74	""
2012-04-20	433.6	10.385	$3.839	41.75	"Another unsuccessful attempt to jump start the Monte Carlo..."
2012-04-25	421.6	10.172	$3.839	41.45	""
2012-05-03	377.3	9.187	$3.839	41.07	""
2012-05-14	414.4	9.854	$3.799	42.05	""
2012-05-18	365.8	8.49	$3.749	43.09	""
2012-05-23	328.8	7.7	$3.749	42.7	""
2012-05-31	380.5	8.472	$3.629	44.91	"Gotta love warmer weather!"
2012-06-07	466	11.059	$3.619	42.14	""
2012-06-20	453.7	10.457	$3.539	43.39	""
2012-07-18	471.8	11.009	$3.499	42.86	""
2012-07-26	450.2	9.595	$3.539	46.92	"I decided to try using NEUTRAL on certain downhill highway stretches. This tank set a new MPG record for this car. My travel included city driving and getting stuck in stop-and-go construction traffic on the highway, so I expect to see better numbers in the future."
2012-08-03	397.9	8.583	$3.489	46.36	"More evidence that my FE gains last tank were no fluke. Once again, I've been getting stuck in stop-and-go construction traffic, yet I've averaged better than 46 MPG for the tank!"
2012-08-07	395.7	8.282	$3.619	47.78	"Another record tank--despite more stop-and-go highway travel. No doubt about using neutral on the highway..."
2012-08-21	382	8.419	$3.699	45.37	"Tire pressure was down about 5psi all around. I have a sneaking suspicion it happened when I had my oil changed recently (they try to be helpful), and I didn't really notice until I got it on the highway."
2012-08-29	458	9.836	$3.759	46.56	""
2012-09-06	401.9	9.076	$3.759	44.28	""
2012-09-14	441.4	9.728	$3.959	45.37	""
2012-09-21	365.6	8.127	$3.899	44.99	""
2012-10-03	380.8	9.017	$3.899	42.23	""
2012-10-11	475.1	11.015	$3.859	43.13	""
2012-10-22	447.4	10.241	$3.799	43.69	""
2012-10-31	385.7	8.851	$3.719	43.58	"Installed 85% lower grille block before starting this tank. Warm-ups seem faster, and coasting seems easier... but it could be a placebo effect."
2012-11-05	417.4	10.278	$3.659	40.61	"More and more cold-weather driving..."
2012-11-09	299.9	7.453	$3.619	40.24	""
2012-11-13	311.3	7.314	$3.599	42.56	""
2012-11-19	373.7	9.375	$3.599	39.86	"Cold weather absolutely kills fuel efficiency."
2012-11-27	458.8	10.989	$3.539	41.75	""
2012-12-05	402.9	10.388	$3.539	38.79	""
2012-12-07	373	8.932	$3.539	41.76	""
2012-12-13	324.9	8.232	$3.499	39.47	"I picked up a tire leak toward the end of the tank..."
2012-12-18	296.4	7.656	$3.419	38.71	"Fixed tire problem..."
2012-12-20	439.7	10.416	$3.419	42.21	""
2013-01-07	337.9	9.229	$3.399	36.61	"Driving in near-zero temps stinks!"
2013-01-10	371.9	9.111	$3.439	40.82	""
2013-01-22	330.9	8.579	$3.399	38.57	""
2013-01-24	369.1	9.786	$3.399	37.72	""
2013-02-01	340	8.686	$3.599	39.14	""
2013-02-05	366.3	8.9	$3.559	41.16	""
2013-02-11	350.9	9.205	$3.599	38.12	""
2013-02-14	411.2	10.087	$3.659	40.77	""
2013-02-26	285.6	7.227	$3.739	39.52	""
2013-03-06	358.4	9.279	$3.659	38.62	""
2013-03-13	346.9	8.862	$3.639	39.14	""
2013-03-18	416.2	10.698	$3.619	38.9	""
2013-03-25	321.9	8.134	$3.619	39.57	""
2013-03-27	416.7	9.934	$3.619	41.95	""
2013-04-03	394	10.491	$3.599	37.56	""
2013-04-09	407.8	9.733	$3.559	41.9	""
2013-04-16	466.2	10.766	$3.439	43.3	""
2013-04-22	445.8	10.557	$3.419	42.23	""
2013-04-26	466.8	11.012	$3.419	42.39	""
2013-05-01	441.2	10.068	$3.419	43.82	""
2013-05-08	365.6	8.623	$3.39	42.4	"New spark plugs."
2013-05-13	422.9	9.396	$3.419	45.01	"Having problems with left-rear tire..."
2013-05-16	363.4	8.856	$3.459	41.03	"More problems with left-rear tire. Swapped to donut spare."
2013-05-21	338	7.569	$3.499	44.66	"Replaced all tires with Michelin Defenders (inflated to 44 psi)."
2013-05-24	394.7	9.304	$3.479	42.42	"Got my MA state inspection. The guy had my car running the entire time."
2013-05-31	447.8	10.663	$3.459	42	""
2013-06-11	419.3	10.463	$3.499	40.07	""
2013-06-13	420	9.714	$3.499	43.24	"The new tires don't roll as well as the old ones (but they do feel a lot better)."
2013-06-19	417.6	9.452	$3.479	44.18	""
2013-06-25	372.6	8.862	$3.459	42.04	"Both rear corners had struts and springs replaced."
2013-06-27	411.4	9.188	$3.459	44.78	""
2013-07-17	447.4	10.032	$3.699	44.6	""
2013-07-24	453	10.495	$3.759	43.16	"Replaced failed alternator."
2013-07-30	340.1	7.945	$3.759	42.81	""
2013-08-01	431.8	9.507	$3.759	45.42	""
2013-08-08	441.4	9.911	$3.739	44.54	""
2013-08-14	423.9	9.53	$3.739	44.48	""
2013-08-21	341.6	7.941	$3.744	43.02	""
2013-09-04	356.7	8.023	$3.739	44.46	""
2013-09-06	368.9	8.176	$3.739	45.12	""
2013-09-11	429.6	9.615	$3.739	44.68	""
2013-09-17	337	7.613	$3.659	44.27	""
2013-09-20	382.2	8.818	$3.639	43.34	""
2013-09-26	476.4	10.911	$3.579	43.66	""
2013-10-01	422.1	9.417	$3.579	44.82	""
2013-10-07	449.5	10.692	$3.559	42.04	""
2013-10-16	456.6	11.023	$3.499	41.42	""
2013-10-24	441.3	10.413	$3.459	42.38	""
2013-11-06	332.5	8.356	$3.399	39.79	""
2013-11-14	379.7	9.323	$3.349	40.73	""
2013-11-21	336.6	8.432	$3.339	39.92	""
2013-12-10	270.9	7.015	$3.439	38.62	""
2013-12-12	333.6	8.881	$3.439	37.56	""
2014-01-06	330.1	9.264	$3.459	35.63	"Cold weather stinks!"
2014-01-20	342.5	9.832	$3.459	34.84	""
2014-01-28	366.1	9.834	$3.459	37.23	""
2014-02-07	352.4	9.525	$3.459	37	""
2014-02-19	289	8.244	$3.479	35.06	""
2014-02-21	369.4	9.018	$3.479	40.96	""
2014-03-04	339.1	9.017	$3.479	37.61	""
2014-03-13	353.5	9.325	$3.479	37.91	""
2014-03-26	378.4	10.44	$3.479	36.25	""
2014-04-19	384.6	10.286	$3.559	37.39	""
2014-05-06	390.7	10.145	$3.699	38.51	"Filled up in the morning. Stranded with cracked head in the afternoon."
2014-08-27	347.6	9.482	$3.539	36.66	"Cracked head put the car out of commission from May 6 to August 15. Hopefully fuel efficiency numbers will recover starting with the next fill-up."
2014-09-10	334.8	8.906	$3.459	37.59	"Timing is definitely way off since the timing belt change, etc."
2014-09-17	374.7	9.459	$3.419	39.61	"Advanced timing by 10 degrees about half-way through the tank..."
2014-09-22	374.2	8.661	$3.399	43.21	"That's more like it..."
2014-10-02	325.1	8.209	$3.359	39.6	"New front brakes. The car now rolls noticeably less efficiently."
2014-10-23	353.9	9.549	$3.179	37.06	""
2014-11-03	376.3	10.591	$3.019	35.53	""
2014-11-17	245.4	6.476	$2.879	37.89	""
2014-11-19	369.4	10.441	$2.899	35.38	""
2014-12-08	308.2	8.354	$2.819	36.89	""
2015-01-13	614.8	17.8	$2.371	34.54	"It has been way, wicked cold out here! Driving in 10-degree temperatures is absolutely killing my mileage. I accidentally topped off the first tank of the year, so I combined it with the second tank. Since I'm not doing nearly as much long-distance travel these days, I've removed the full-size spare from the trunk (I've still got the donut spare in there). I've noticed an improvement in acceleration. Hopefully, I will notice better fuel efficiency in the city."
2015-01-29	315.6	9.786	$2.099	32.25	"Increased city driving combined with snow storms and sub-zero temps has lead to my worst tank since I've owned the car. About two-thirds through the last tank, I switched to a full-synthetic motor oil."
2015-02-06	240.3	7.318	$2.149	32.84	""
2015-02-18	327	9.7	$2.199	33.71	""
2015-02-25	377.6	11.181	$2.359	33.77	""
2015-03-09	295.8	8.738	$2.459	33.85	""
2015-03-12	343.2	8.947	$2.499	38.36	""
2015-04-08	351.4	10.272	$2.339	34.21	""
2015-04-16	330.5	9	$2.459	36.72	""
2015-05-29	361.9	9.91	$2.699	36.52	""
2015-06-09	326.7	8.067	$2.739	40.5	""
2015-06-24	340.4	8.063	$2.779	42.22	""
2015-07-15	353.2	8.437	$2.739	41.86	""
2015-07-23	502.2	11.064	$2.719	45.39	""
2015-08-25	418.8	10.165	$2.579	41.2	""
2015-09-11	336.1	8.167	$2.359	41.15	"I got the AC working, and I've been using it."
2015-09-24	433	10.507	$2.239	41.21	""
2015-10-08	293.4	7.234	$2.159	40.56	""
2015-10-16	379.9	8.952	$2.119	42.44	""
2015-10-29	321.9	8.078	$2.079	39.85	""
2015-10-29	395.6	9.779	$2.039	40.45	""
2015-11-03	363.7	8.684	$2.059	41.88	""
2015-11-17	411.9	10.413	$2.119	39.56	"Left-front wheel bearing needed replacing."
2015-11-25	334.2	8.68	$18.39	38.5	""
2015-12-02	432.4	11.127	$2.119	38.86	""
2015-12-15	309.7	7.611	$2.119	40.69	""
2015-12-16	402.4	9.831	$2.079	40.93	""
2015-12-22	382.1	9.467	$1.999	40.36	""
2016-01-05	291.7	8.108	$1.959	35.98	""
2016-01-07	375	9.28	$1.959	40.41	""
2016-01-12	339.7	8.362	$1.939	40.62	""
2016-01-15	376.6	9.738	$1.939	38.67	""
2016-01-21	329.2	8.893	$1.899	37.02	""
2016-01-28	302.4	7.519	$1.839	40.22	""
2016-01-29	409	9.859	$1.839	41.48	""
2016-02-08	320.7	8.377	$1.799	38.28	""
2016-02-12	272.8	6.925	$1.799	39.39	""
2016-02-22	292.5	7.321	$1.719	39.95	""
2016-02-24	363.9	9.541	$1.699	38.14	""
2016-03-08	445.1	10.661	$1.719	41.75	""
2016-03-14	341.7	8.222	$1.859	41.56	""
2016-03-29	409.7	10.608	$2.019	38.62	""
2016-04-13	405.3	10.836	$2.039	37.4	""
2016-04-25	330.1	8.05	$2.139	41.01	""
2016-05-05	347.9	8.495	$2.199	40.95	""
2016-05-09	399.2	9.416	$2.199	42.4	""
2016-05-18	285.8	6.887	$2.199	41.5	""
2016-05-20	388.7	8.802	$2.199	44.16	""
2016-06-01	376.3	8.598	$2.299	43.77	""
2016-06-09	378.1	8.648	$2.299	43.72	""
2016-06-23	353.3	8.606	$2.299	41.05	"Replaced all fuel injectors just before fill-up."
2016-07-19	385.6	9.27	$2.199	41.6	"Replaced fuel filter at 91 miles. Replaced starter and cleaned throttle body at about 250 miles."
2016-07-28	401.3	8.725	$2.099	45.99	"Heat wave required running the AC at times."
2016-08-24	446.1	9.764	$2.599	45.69	""
2016-09-20	309.9	7.199	$2.199	43.05	""
2016-09-29	346.9	8.395	$2.179	41.32	""
2016-10-06	376.4	10.03	$2.349	37.53	""
2016-10-27	306.6	8.247	$2.599	37.18	"Installed new IAC valve, cleaned throttle body, installed new spark plugs, installed new air filter, reset ECU. This was 93 octane fuel."
2016-11-01	361.5	10.049	$2.599	35.97	"93 octane again. I upped my max speed to 65 mph."
2016-11-16	356.3	9.772	$2.599	36.46	"93 octane again."
2016-12-15	360.2	10.446	$2.159	34.48	"Filling up with 87 octane again."
2017-01-24	313.9	9.276	$2.299	33.84	"Installed new cap and rotor at 43 miles in."
2017-01-30	356.3	9.244	$2.259	38.54	"Replaced both O2 sensors at 217 miles in."
2017-02-07	330.5	8.934	$2.259	36.99	""
2017-02-14	310.8	8.078	$2.299	38.47	""
2017-02-21	328.3	8.717	$2.279	37.66	""
2017-02-23	369.3	8.986	$2.239	41.1	""
2017-02-28	409.7	10.152	$2.219	40.36	""
2017-03-09	353.1	9.264	$2.219	38.12	"Gas tank is starting to have issues..."
2017-03-13	359.8	9.495	$2.179	37.89	""
2017-03-16	338.9	9.14	$2.219	37.08	""
2017-03-28	310.1	8.379	$2.199	37.01	""
2017-03-29	413.2	10.121	$2.239	40.83	""
2017-04-20	796.2	20.326	$2.329	39.17	"Haven't been filling up as frequently because the top of the gas tank leaks..."
2017-04-25	369.8	9.601	$2.599	38.52	""
2017-04-27	366.2	9.405	$2.399	38.94	""
2017-05-02	412.2	10.06	$2.399	40.97	""
2017-05-08	422.6	10.834	$2.399	39.01	""
2017-05-09	355.7	8.967	$2.479	39.67	""
2017-05-23	403.7	10.39	$2.379	38.85	""
2017-06-07	392.4	9.56	$2.449	41.05	""
2017-06-29	343.6	9.116	$2.179	37.69	""
2017-07-11	320.4	8.657	$2.239	37.01	""
2017-07-26	337.4	9.187	$2.259	36.73	""
2017-08-04	320.2	8.32	$2.299	38.49	"Cylinder #4 compression measured at 30 (should be 120)."
2017-08-17	338.8	9.153	$20.21	37.02	"I've cut way back on any hypermiling..."
2017-10-18	2142.8	59.882	$2.673	35.78	""
2017-11-01	299.7	9.549	$2.659	31.39	"Record low mpg for this car. It didn't help that the car was almost completely loaded with trade show stuff for the entire tank. I expect a rebound with the next tank."
2017-11-06	305.6	8.787	$2.539	34.78	""
2017-11-07	282.6	8.051	$2.619	35.1	""