Thread: Two Questions..

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One. I have a 96 Chevy Blazer with 91,000 miles on it. 4.3 V6. It has something that is making the battery drain after I turn it off. I can let the truck sit over night, and it barly starts, or just clicks. I bought a new Interstate battery. Still the same thing. I checked for lights on in the glove box, and under the hood. I brought the battery back and had it checked for a load. The battery is fine.. Will one of those testers that plugs into the computer tell me what might be on to cause that drain??, or how do I find whatever is draining.. I wouldn't think it all could be drained down from just the radio memory..

Two. A Lady where I work has a 2010 Toyota Tacoma. It was getting 23mpg. Now it seems weekly to go down to 21mpg, and her lowest has been 18mpg. She went to her dealer. He said that the injectors needed cleaning.. She already did that, but that didn't help.. Any thoughts on this as well?? Thanks.. Al

One way to check a drain on the battery is to disconnect the ground cable interrupting the battery's circuit and then hook up a test light between the ground cable to a chassis ground.If the light lights up you have a hot to ground issue.You then go to the fuse box and narrow down which circuit is shorted out by pull fuses one at a time until the test light goes out.

Thanks. I will try that..

Gary's suggestion will get you started, however; most cars will light a test lamp as they draw current all the time to run the clock, security system, OBD, etc.. They don't draw a lot, but they will cause a test lamp to glow. You've got something drawing substantial current and you'd be better served with a multi-meter that measures current (amps). You can then pull fuses and find the circuit that is drawing a lot of current and work backwards from there. A likely culprit is a stuck switch (or relay).

As to the Tacoma - might just be the crappy oxygenated gas that's mandated in the winter months..

Good luck and let us know what you find..
Glenn

I was thinking last night that a couple of years ago I put on a trailer hitch. I used a u-haul harness on it. I followed the instructions, but I better double check those connections first.

As far as the tacoma goes.. would a octaine booster help??

Originally Posted by slantback37

I was thinking last night that a couple of years ago I put on a trailer hitch. I used a u-haul harness on it. I followed the instructions, but I better double check those connections first.

As far as the tacoma goes.. would a octaine booster help??

If you did the wiring harness two years ago I doubt it's the source of a new problem, but then again you cannot rule it out. Like Glenn says, use a meter to really hone in on current draw. Most of the newer fuses have two tiny holes on top testpoints.jpg to check them in place. For your problem you can check the amps across the fuse, looking for one that kicks up the reading above a few milliamps. You can also check for blown fuses, positive on each point in turn, negative on a good ground - when you lose 12V on one side you've found the open fuse.

On the tacoma, don't waste money on octane booster. Higher octane slows the burn across the cylinder to prevent "ping" and detonation and will actually hurt mileage on a vehicle that doesn't need the slower burn. The fuel injector cleaning that the dealer is talking about is pulling the injectors and cleaning them out with a precision probe, sized for the injector bore. The liquid cleaners are going to take more time to show improvement, if any. I'd tell her to add injector cleaner to every tank of gas for a couple of months and see if it helps. If not, the injectors could indeed need mechanical cleaning.

She had the injectors cleaned at the dealer..

Originally Posted by slantback37

She had the injectors cleaned at the dealer..

If that did not help then I'd agree with Glenn - around here it's not unusual to see a 10-15% reduction in mileage as they switch to winter blended fuels. Maybe it will improve as the season changes?

Originally Posted by 1gary

One way to check a drain on the battery is to disconnect the ground cable interrupting the battery's circuit and then hook up a test light between the ground cable to a chassis ground.If the light lights up you have a hot to ground issue.You then go to the fuse box and narrow down which circuit is shorted out by pull fuses one at a time until the test light goes out.

Put the light or meter between the terminal (cable) end that you just removed and the BATTERY POST! If it lights or the meter moves, then a circuit is drawing.

If you connect the light between the cable end and the chassis, nothing will happen.

Rspears. Would it be the same if she used preimium gas??

Originally Posted by slantback37

Rspears. Would it be the same if she used preimium gas??

Yessir. Your engine gets the most power and best efficiency with the lowest octane fuel that it can run without detonation, indicated by "ping" under heavy load. If it's a stick, put it in high gear at a moderate low speed, floor it and if it does not clatter on regular gas then any higer octane rating is just being wasted, and will actually run less efficiently.

Ask her if she switched gas stations/companies because some brands are pushing higher etanol % than others--as rule of thumb--milage wile vary about linear with the percentages of etenol---ie---go from 10% to 15 % milage will drop 5%---on 20 mpgallon = 1 mile

Just between one Holiday station, to another on the other side of town.

Maybe the station pumps are off on the gallons--I have been known to take 5 gallon cans and check them---

Don't know. She left work for the day.