My 98 Mitsubishi Eclipse is Acting Weird. Code P1500

by A Warren
(Indiana)

When I accelerate it goes fine but when I try to really give it some gas (not hotroding it but just speeding up say to get on the highway) it starts feeling sluggish and putters then evens out but if I continue to accelerate it does it. I have a couple of questions. 1) Where should I start looking to find the problem. 2) It didnt stat doing this until I used k&N air filter cleaner on my air filter. It is also reading a p1500 trouble code. If anyone has any ideas about this I would apreiciate it.



Steve Says,

Thanks for using my website. I'll do my best to help you with your obd code problem given the information that I have.

Let's start with what we know for sure. The trouble code p1500 is for the alternator circuit. This means that either the alternator is bad or the wiring or computer is bad. The best thing to do is have the alternator "load tested" at either an auto parts store or a repair shop. Be sure that it is load tested. Some places test them, but they don't test them with a "load" on them (like when you are driving using lots of electrical components). This can sometimes cause the alternator to test good when really it is bad when it is put under a load.

If it tests bad then you need to replace it, if it does not test bad then you need to very carefully inspect the wiring going to the alternator. You need to pay special attention to the connection that goes into the alternator. Sometimes these can come loose or corrode and cause a bad connection.

If your alternator is faulty and is not putting out enough amperage to run your electronics and electrical accessories on your car then it could cause the problems you are having when you are driving. The alternator is the first thing to check for this symptom too.

If the alternator tests fine, then you need to check the fuel pressure. If it is low then it can cause the same problem that you are having. You can get a fuel pressure gauge to fit your car from any good auto parts store. While you are there you can ask them what your fuel pressure should be. Then just hook it up and start your car and read the pressure. If it is low then you need to start by replacing the fuel filter. It can cause low pressure if it is clogged. If that does not fix the low fuel pressure problem then the next most likely thing to cause it would be the fuel pump and/or fuel pressure regulator.

Please leave me a comment if you need more help and when you get this problem figured out. I hope this has helped.