First off, I would like to introduce myself. Names Brent in FL. I've done little work on Neons(basic ****, starter, alt, etc...) as I drive an RX7 and thats enough to keep me busy....

Lately my gf's car(97 Highline) as been acting up. Runs like ****, eating gas and rough idle when at a stop(w/ brakes pressed).

I did some reading up on this forum(which I must say has been the most useful Neon forum yet) and did some error code checking and came with this:

42-Fuel pump relay control ckt, Auto shutdown relay control ckt, No ASD relay output voltage at PCM, Fuel level sending unit volts out of range, Fuel level unit No change over miles

43-Multiple/single cylinder misfire(Which I should say is quite obvious; no brainer)

(Now, keep in mind, I dont work on these things...)

The Question: Error Code 42; What exactly does it mean? ASD & PCM(meaning)? What the hell do I need to fix this machine?


Thanks-

Brent

 

More info please, could be lots of stuff. Any noises, burnt circuts, check all of your relays, they're under the hood next to the fuses. Should be some black cubes cost about $9. See if any of the prongs are burnt, especially the first two on the top from the left. Could be the fuel pump, which would suck for you. Or her...?

 

No real noises, except when the A/C is running, its a faint high pitched noise(you cant hear it unless the radio is off) when the A/C is kickin on and off. No burnt circuts, all the relays seem to be good. What could be wrong with the fuel pump? ...I might have to change it, huh?........damn.

 

Oh yeah, itll be her problem. I told her if this thing causes anymore problems, it gone.

 

If you check out modern performanc you can get the FP cheaper than at a parts store- I think it was less than $120. The high pitched keening could be the computer cooling itself off. You could need a new ECU- engine control unit. That'll run you from $200-$500, but is easier to swap than a fuel pump. To swap the pump drop the tank, pull the pump, put in the new one and re-install. Sounds easier than it is. But get a few more oppinions b/f you do anything.

 

Sounds to me like you need yourself a tune up my friend.

The code 42 is in almost direct correlation to the code 43 (multiple/single cylinder misfire).

I'd start with the basic things first. Change the spark plugs, wires, reset the PCM (Power Control Module or Computer) and see how she runs.

The 42 could be because of the misfire or it could be that the pump is actually bad. I'd change the plugs before you delve into forking out he cash for the pump.

 

Nope...I have done 3 tune-ups on this thing after it started doing this(About a month & a half ago). How do I reset the PCM? Now, If the fuel pump was bad, wouldnt it not even run? Or is it just putting out the wrong signals, hence the misfireing/rough idle? Thanks guys, appreciate the help.

-brent

 

Disconnect the negative battery cable for 30 minutes to 2 hours. That'll discharge the PCM and reset the codes.

If the pump was actually bad it would have a real tough time starting and running but since you can start it and it does run then its got to be something else. The pump is still a possibility but you are better off starting witht he easiest things first and eliminating what it isn't.

 

could defineately be the pump. We had a '95 come in with driveability issues (low power, poor mileage, some hard starts). It threw similar codes and when we did a fuel pressure test it was running 19psi out of the specified 48psi. Swapped the pump and the car now runs like a champ. Two things to note; first this car had a severely rusted filler neck which likely contributed to the failure in a case like this I wouldn't bother swapping the pump if your not gonna fix the filler neck to prevent contaminating the new pump. Second, a lot of places will tell you you have to change the entire sending unit, not true. If you look hard enough you can find the pump seperate and it's pretty easy to swap the pump out of the sending unit.

 

Not to insult yu guys, but have you tryed changing the fuel filter?

Your problem sounds just like a filter. Rough running, slow pick up, gas milage goes, will eventually stall a lot.

Cheap and easy, and not a bad idea just to seewhat happens.

When the fuel is intermittent, that can cuase the pump readings to go whako, and to cause the computer to constantly make adjustments, which makes things worse.

If you are always buying cheap gas, you should change the fuel filter between 15,000 and 20,000 mile, no matter what you drive.