” My 2002 Infiniti I30 won’t start. The fuel pump won’t work, but it will start if I hot wire the fuel pump. Then it runs fine. I traced the problem to the main computer, which is burned inside. My question is this–what can I check BEFORE I buy a new expensive computer to ensure it won’t burn out again?”
Well, you’re certainly being smart not just buying the computer and hoping that will fix the problem. You’d want to check the wiring going to the fuel pump for any type of short, and check the fuel pump to see if it’s using too many amps and is wearing out itself. BUT, also realize that the computer itself receives unfused power from MANY different sensors. So check them all, especially the idle air control sensor, because I’ve seen water intrude into the IAC sensor on those Infinitis, which shorts the sensor out. Then this feedbacks to the computer and shorts it out. I fixed one last year with the same problem as yours, and it was a leaking IAC valve that shorted out the fuel pump driver in the computer. Aren’t modern complex cars fun to work on?
” Thanks for saving me a ton. I cleaned out the MAF sensor and the throttle plate with mass airflow sensor cleaner. Just like you’ve said in other posts, I got a can of MAF cleaner that CRC makes at Auto Zone. Now I know how to keep my VW running smoothly. But how often should I do this cleaning?”
Oh, you could clean it out a couple times a year if you want, since it’s such an easy job on your VW to get to those parts. But it probably won’t be necessary to do it that often (unless it starts running poorly again.) Once a year is generally fine in most circumstances.
“Hi , I was told that an old car not able to pass State Inspection can be stopped and given a voucher for $3500 for purchasing a new car. I have a 23 years old car that may not pass next month. What do I need to do in order to get that voucher? Thanks for your helpful a prompt answers. Regards, Peter”
Well, different states have different laws, so check the laws in your area. Here in Texas it’s a deal that you get a certain amount of money to be credited for buying another car if your personal income is below a certain specified amount. If you contact the DPS through phone or their www.txdps.state.tx.us/ website. The rules are always changing, so check BEFORE you take a leap. And realize that whoever accepts these vouchers is probably going to hit you pretty heavy on the price they charge for another car (these deals often negate any bargaining over price, so Be Wary.)
” I want your professional advice. The temperature gauge on my 2001 Chevy Venture acts wildly. It goes from half to three quarters to even higher. But I don’t lose any coolant and it runs fine otherwise. I even had the dash unit replaced with a GM rebuilt unit and the temperature sending unit on the engine changed also. BUT, it still does the same thing. What should I do now?”
Well, make absolutely sure you’re not losing coolant and that the head gasket on the engine isn’t starting to blow, but I assume the other mechanic has already checked this stuff out. If so, I’d personally live with it. I’ve seen many of those Ventures just act that way. Something in the dash unit and the software just does that in many of them as they age. I have personal customers who’ve lived with those “nutty” gauges for years, and it gets REALLY hot here in Texas. They’ve had no cooling system problems otherwise, so they just live with it.
” Hi , can you please tell me how to know which wire is the ignition wire when wiring the stereo and can i use a normal light tester probe to find the ignition wire. Also if i want to wire couple of things to the ignition wire, do i use the same wire to connect all the products or is there another way of doing this.”
Personally, I would never wire anything off the ignition wire, it can mess things up (there are actually more than one wire which get power when you turn the ignition on.) If you do want to find one to use just for that little ignition wire on a modern fancy radio system, just take the plastic off the steering column to access the wires, and when you turn the key on, check them with a test light and when the light comes on, that’s got power. BUT, you really should wire other accessories directly off the battery positive post, using the correct gauge wire and correct fuse for whatever application you’re using. That way you won’t mess up the electrical system by hooking up something where it shouldn’t be (it can really open up a can of worms that you won’t like the results of.)
” My 2001 CRV is idling poorly. There are no trouble codes, and I read your advice here, so I cleaned out the throttle valve and the whole throttle body. It was full of carbon, but it still idles poorly. What should I try next?”
Well, those little Honda engines often get carbon build up on the valves inside the engine also. I’d advise having the engine carbon cleaned by a mechanic with a power flush machine. And while you’re at it, AFTER having the valves cleaned of carbon, have the valve adjustments checked. I’d seen quite a few Hondas with valves that are badly out of adjustment cause severe idling problems. And your Honda does have adjustable valves on it (many cars don’t these days, they use hydraulic lifters that are non adjustable.)
Cons Santos’s question:
” Just recently my AC evaporator has a leak and has been replaced by a technician with a new evaporator. However, during engine idle(RPM 1000), cooling is poor while during high RPM 1500 and Up, cooling improved significantly. I hope you have a suggestion on what to do next. Thanks.”
It could be a few things doing that. One, he just might not have put the correct amount of refrigerant in. Two, he may not have changed out the AC drier, in which case the system wouldn’t flow right at low speeds ( ALWAYS change the drier when the system is opened up.) Three, it could be a cheaper aftermarket evaporator which just won’t work as well because the cooling tubes inside it are too small, I see that a lot with cheaper Chinese made replacement evaporators. These are the three most common mistakes people make when working on an AC system that would cause your exact problem. Good Luck,
Jimmy Alvarez’s question:
” I have a 85 Nissan 300zx and for some reason the reverse light wont turn on when i put the car in reverse and that’s the only thing that wont let me pass the emissions test i already changed the bulbs but no results…what can i do?!?!?”
Well, 99 percent of the time it’s the back up light switch on your transmission that’s gone bad. Generally the only place that sells such a part is the dealer, so go there and they can sell you one and show you on their computer where the switch is on the transmission. If that doesn’t fix it, then either the wiring has a short in it or the piece inside the transmission that turns the switch on when you go into reverse would be broken (rather rare, but I’ve seen it happen.) Normally though, it’s just the switch on the transmission gone bad.
” My 1998 Chevy Malibu makes a clunk when I go over larger bumps. A shop changed out the strut mounts, the torsion bar bushings, and the front struts. But the clunk is still there. I took it back and they said nothing was loose now. Have you ever seen this before?”
Well, as a matter of fact, I was stung by this very same problem last year. It turned out that the outer tie rods were making the clunking noise–even though they had no play in them when pulled on, and physically looked perfectly OK. It’s a rare one, but it happenned to a Malibu I was working on, and it took me a while to figure that out. As tie rod ends are pretty inexpensive, you might try that next.
” My 2002 New Beetle is pinging and has poor acceleration. It has code 17536 for long term fuel trim lean. People are trying to sell me all kinds of stuff for hundreds and hundreds of dollars. What do you think I should do?”
Well, before you spend a bunch of dough, I’d advise changing out the main fuel filter and cleaning the Mass Airflow Sensor (or MAF.) VWs are notorious for getting crud on the MAF sensor and then running lean. And fuel filters do clog up over time and when they do, not enough gas can make it to the injectors, so the engine can run lean. I’ve cleaned lots of VW maf sensors to get them running normal again, it’s a pretty common problem. so try that before spending a bunch on parts you may not need. And if you do need a new MAF sensor because the old one is just plain worn out electronically, you can purchase a quality remanufactured unit instead of the VERY expensive VW OEM new sensor.