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2000 Plymouth Neon
Dash reads 130,000
car has rebuilt jasper motor which has actual of 95,000

recently replaced ignition wires. car just returned from 8 hour drive.

I was driving when I felt the car studder so I pulled the car over. I shut off the ignition and restarted the vehicle. The rpms revved up to about 3k then dropped back down to 1.5k with a constant up and down hesitation. The brake pedal is very stiff and when the car is put into drive, because the rpms are at 1.5k, the vehicle moves forward without me giving gas and not being on a hill. When the car is shut off, theirs a violent shake before ignition dies. I did the key to ON position 3 times to read trouble codes but it just flashes FUSE constantly. Checked under hood fuse block as well as driver side panel and none as I visually see are blown. I've heard of fuses being behind the instrument panel but when I removed it I didnt see any, only some screw in type pieces which I couldnt remove. any ideas of what could be the culprit to my problem?

Sounds like a bad vacuum leak. I'd bet my lunch money on it.


Listen under the hood for a light hissing sound. You can spray brake clean or ether around the engine bay and see if the engine speed increases. That will help isolate the leak by essentially adding unmetered fuel into the intake stream, causing an increase in revs. Obviously, a thorough visual inspection is the absolute first thing you should do.

Never heard of "FUSE" coming up on the dash. There's really no way the PCM would be able to tell that a fuse blew. It can sense voltage and/or an open circuit, but not a popped fuse. Very interesting, maybe someone who's come across this can chime in.

The stiff brake pedal/ surging rpms would mean the large vacuum line going to the brake booster is a likely culprit, or the booster diaphram has failed. But it doesn't hurt to check in other places. This just would be the first place, other than the bellows, I would check.

The fuse part, I have seen other threads on.

viewtopic.php?t=36070

viewtopic.php?t=27953

Hope it helps.

as for your fuse issue you may have a light a switch or something still on. thats what mine was. my fuse was the interior. your sounds like it could be your ignition if you are having a hard time starting the car. if the car dies the easiest way to find out which one it is, you need to test and see which fuse is being over loaded

This fuse problem has been around for the past 5 months. I never noticed anything left on and always had full battery life so I didnt jump to fix the problem. I do not keep a dome light bulb in my car but the problem started before removing the bulb sometime ago.

If the idle is still surging then remove your IAC, clean it with brake clean (avoid carb cleaner), let it dry a bit (a couple of minutes), and re-install.

You should be good to go

In addition to what Dante said, if the idle is till going up and down, swap in a (known) good TPS - when those go bad, it can cause the surging.

Personally, I think occ-dem is correct, but we'll see whan the OP gives us an update.

Danteneon wrote:If the idle is still surging then remove your IAC, clean it with brake clean (avoid carb cleaner), let it dry a bit (a couple of minutes), and re-install.

You should be good to go