I don't know much about cars, or the symptoms of anything faulty, so I'm hoping someone with more expertise can take all the info and give me a step in the right direction before I take it to a mechanic:

My issue started about a month ago. Basically, when I start the car, it starts fine, but when I put it in reverse it putters a little as I back out of my driveway. When I put it in drive and press on the accelerator, it starts to go but then stops moving. The car doesn't die, but just doesn't accelerate even tho my foot is pressing on the accelerator. There is no sound like revving as this happens. It happens for a couple seconds and suddenly starts going again and drives fine the rest of the ride, no hesitation of any kind after stopping at a light or anything. The problem doesn't happen every time I start the car, but I'd say a good 95% of the time. After the initial 10-15 seconds upon start up, I have no issues with hesitation or anything. When it first happened, I put some Seafoam in the gas tank when it was close to empty, changed the fuel filter, and then put some Lucas fuel system cleaner in it before my next fill up. Up until two days ago, the check engine light wasn't even on. It came on, and as soon as it did I took it to Advanced and got a P1635 code reading. Did a little research and saw that the code has to do with about 4 or 5 things, which I'm sure the pros are familiar with. The light has since gone off, so now I'm not even seeing the check engine light. With the description of how my car is riding along with the error code, can anybody possibly narrow down what it is? I'd really appreciate any kind of answer. Thank you.

When searching i saw your posts on other forum, the info is good you just have to go out with a meter and check it, no one is going to be able to narrow it down further over the internet.

Code P1635 is a problem in the 5 volt reference circuit.

The PCM uses the 5 Volt Reference A circuit as a sensor feed to the following sensors:
TPS,MAP, EGR, FTP.

you will have to check for the reference voltage on all these

Thank you. Could you tell me what kind of meter to use?

A multi meter that reads volts, amps and ohms. They are pretty inexpensive.

there are write ups on a 3.8, but should be similar, you are looking for the pin that has the 5v on it
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