Hey guys, I've been a little Ape reading my eyes out for the past week and figured I may as well join to write a few questions.

So, I've got a 2001 Neon 2.0 SOHC 5sp. When I got the car a week ago, it ran like absolute crap. I changed my valve cover gasket and all the little seals that go with it, along with a new set of NGK plugs. I had to re-install one plug cylinder thingy... I got all the oil cleaned out, cleaned up the wires with brake clean and put everything back together. The car now runs awesome when cold, but as soon as its at """normal operating temperature""" it starts to hesitate. Its almost a sputter, feels like a TPS messing up... I checked the catalytic when I got home after a hard run but being winter, little bit hard to check if it got red... Yes the plug wires are new also

So, where do I start? When I prime the pump, it sounds "solid" Would a came angle sensor cause any of these issues?

 

Just used my scanner, I've got a P0420 catalytic 1/1 efficiency error. I guess that could be a o2 or a plugged cat. The cat is in such a pita location its going to be hard for me to cut it out and weld some pipe in there. I have yet to jack this car up... does the cat just unbolt? If so, I can unbolt it and make a "test pipe"

edit: just read factory manual... so there is two cats. Which one is faulty?

 

There is only one cat on the 2gn sohc neon. There are 2 types of cat's.

One is the normal cat, one is a LEV cat that is found mostly on CA cars like mine, it's just larger and costs more.

A simple cat delete will require a pipe and an 02 bung plus a spark plug defouler or your still going to get a cat code but "rich".

Just google neon downpipe, they can be had for 40 with a flexpipe and 02 bung welded in, some cheap headers include them.

It's quite possible this is not your issue though and your possibly skipping or one of your other sensors is out of wack causing the cat to nail a code.

As far as cam sensor goes usually it will just fire non sequentially if it fails.....so loss of power but not total loss of power.

I would check the map sensor and inside intake for starters to see if oil is pooling there, the pcv system is not great on this particular car and can cause numerous drivability issues including improper map sensor values.

 

I decided to ditch the aftermarket wires and I purchased a set of OEM wires. I changed the cam sensor also. So far so good, but no insurance so going to be hard to test it. I am now reading a IAT sensor code, but the thing is plugged in. My alternator light is also on now, but I didnt touch anything regarding the alt.

 

Ahh, that I might be able to help with.

First check the radiator support.

Look on either side of radiator see those ground straps. I'd check the one on drivers side, then I'd check the one on pass side strut mount.

There's another from trans to battery tray and then one more from battery to front right side of fuse box.

 

so after changing cam sensor and throttle positon sensor, it feels as if nothing was changed. The engine definitely hesitates and responds to where my foot is on the throttle, so it is for sure a throttle issue.

 

Did you manage to fix the alternator light issue?

Cam sensor is only going to fire injectors sequentially.

Throttle position sensor is simple to check technically.

If you unplug it and snap the throttle it will bog real hard, if it doesn't I would suspect faulty wires to tps.

Really need to go back to basics for this, cars need 3 things, air, fuel, spark and to run optimal they need the right amount of each.

Poor throttle response could be numerous things.

low fuel pressure

weak spark or no spark on a coil will do it to causing a skip.

map sensors get clogged due to a flaky pcv system casuing drivability issues.

clogged cat

timing

Thats just to name a few.