420A 2gNT Running rich, Loss of power

[Pozobyt]

my 99 stock 420a eclipse has been running rich and missing for awhile now and I can't figure it out. every time I get the codes read, it just says Rich, misfire on bank 1. I've tried gutting my Cat, didn't help. I have some new injectors to throw in there and see if that fixes it.

along with the rich condition, it's sputters when accelerating sometimes, and it sometimes stalls in reverse, and it has barely any low end power at all. it's hard to pull onto the interstate or anything because it has lost so much.

What can I try? and what would cause all of this?

thanks

 

[TotalEclipse21]

Have you had a tune-up recently?(plugs, wires, etc.)

 

[97ClipseGSX]

yea, wires and plugs can make a big difference with your car. Mine was starting to have the same problem as yours. It didnt feel like i was getting the power i was supposed to be getting, so i changed my spark plugs to NGK Iridium. It helped out alot. Make sure your spark plugs are gapped correctly as well.

 

[Pozobyt]

I changed the plugs when I got the car in july, but I haven't done the wires yet. I actually took the MSD ignition coil I had on there off, and put a stock one on just for the hell of it, and it helped alot. I'll try changing the wires and see if that helps any more!

Thanks guys!

 

[NeMiZiS]

First off why did you gut the cat?
That isn't going to help anything as far as your miss firing.
I would change the wires and check the gap on your plugs.
How many miles is on the motor?
It might need to be seafoamed it can work wonders.

 

[Pozobyt]

I gutted the cat to see if that would help my power loss and rich condition.

Thanks, the gap is good, so I'll try changing the plug wires.

Oh, and it's got 150k Miles on the motor. I did seafoam it. didn't seem to help, but I can try doing it again.

 

[97ClipseGSX]

Yea, The wires would be the only thing i could think of. If thats not it, then im out of ideas.

Sorry if that doesnt help and good luck.

 

[Pozobyt]

I'll replace them tomorrow and post results

 

[Fotowntalon]

1) gutting a cat actually loses power in itself
2) did you change the oil and plugs after seafoam? cause it down foul the plugs and goop the oil.
3) the MSD coils are good, but they are known for going bad early, so that makes sense for your stocker improver things.
4) How are your 02 sensors, they have a lot to do with A/F Ratio and with that being of alone could cause misfires

 

[Pozobyt]

The power issue didn't really improve, or get worse after gutting the cat.

I haven't changed the plugs after the seafoam, but they look good.

I replaced the plug wires today, and it seemed to help even my idle out, still not like it should be.

I'm going to try changing the 02 sensors, I don't know if they're bad or not because it's only throwing a rich code, so I'll change them anyway, and see what that does.

I'm going to try to get a video up in a bit to show everyone what's going on

 

[Black'95]

Do the 420a engines have mass air sensors? If it does, maybe check that. I'd also check your vacuum lines for leaks and stuff. +1 for the O2 sensors as well.

 

[smrogers5771]

front or upstream 02 sensor....... upstream will control amount of fuel and works along with the map sensor. So im laying my money on upstream 02

 

[Pozobyt]

front or upstream 02 sensor....... upstream will control amount of fuel and works along with the map sensor. So im laying my money on upstream 02

Awesome, thanks. I didn't know which one was which, so I was just going to replace both, you just saved me money

 

[Fotowntalon]

Do the 420a engines have mass air sensors? If it does, maybe check that. I'd also check your vacuum lines for leaks and stuff. +1 for the O2 sensors as well.

negative we have a MAP sensor

 

[Pozobyt]

DSM Forums - IMG 0027

Here's a video of what it's doing on startup, I didn't miss too bad but it doesn't start up like it should

 

[smrogers5771]

yeah man no problem im glad i can help save some cash haha i had a similiar problem once ... my down pipe cracked off after the turbo and well needless to say the O2 sensor wasnt picking up any exhaust gases and therefor could not tell the ECU how much fuel to add... so the car missed a bit, also bucked and just didnt run right at all.... so got the new down pipe and there ya go... if the down stream O2 goes out it will rich up the fuel mixture but not a whole lot like the upstream or front O2 sensor would....

 

[Pozobyt]

yeah man no problem im glad i can help save some cash haha i had a similiar problem once ... my down pipe cracked off after the turbo and well needless to say the O2 sensor wasnt picking up any exhaust gases and therefor could not tell the ECU how much fuel to add... so the car missed a bit, also bucked and just didnt run right at all.... so got the new down pipe and there ya go... if the down stream O2 goes out it will rich up the fuel mixture but not a whole lot like the upstream or front O2 sensor would....

Oh wow, yeah I'm not sure if it was making much of a difference, but there were a bunch of holes towards the end of my exhaust where the muffler bolts on at the back of the car, I guess from where the previous owner tried to weld on an exhaust tip.

So I took that off and bolted on a stock muffler. I'm not sure if it helped though, or if I just can't tell as much because the car is quieter.

I haven't gotten a chance to change that o2 sensor yet because I'm in the middle painting the car, and i'm trying to get all of the primer sanded so I can finish it, plus it was raining all day today, but I'll update as soon as I get it on there.

 

[Fotowntalon]

holes drilled in a muffler are a poor mans way of tuning. All it really does is make it loud as hell.

 

[Pozobyt]

holes drilled in a muffler are a poor mans way of tuning. All it really does is make it loud as hell.

Yeah, It sounded pretty horrible haha, especially since I gutted the cat.

It sounds better with the stock muffler on it.