Resolved 2GNT No start after O2 replacement

[Eclip97gs]

Hello everyone, I am new to DSMs but have a family in the automotive business all my life, so I can stumble myself around my new 97 Eclipse GS when it comes to pretty much anything that needs to be done. I ran into a issue I can't figure out.

I just picked up this Eclipse from a older gentleman that has had it since new. It was very well maintained but still has little issues here and there I'm trying to tackle one at a time. The original owner has used a little mom and pop shop since the car was new to do any work or repairs. I can tell the shop he has had things apart here and there just by noticing misc wires tapped into (headlights run on new plugs) and factory harness plugs not plugged in etc. It also appears the whole fuse box under the hood has been replaced as well as the ECM. Confirmed the ECM is new by original owner but he doesn't know much about what all has been done, he just let them do whatever it needed and paid the bill.

I say all of this because it makes it harder for me to work on because I'm pretty sure some parts have been replaced with different year Eclipse parts etc... I haven't contacted the shop to see if they will tell me just what all they have done over the years.

Ok, now the new issue I'm having. The car would start right up and run great but sometimes right when it heats up, like when it goes into closed loop it would die. Starts right back up but then runs a little rough after. It doesn't seem like it's really missing bad just a slight bit rough. I have been getting horrible gas mileage since day one, I recently have also began to smell raw fuel here and there. The exhaust system was just replaced from the header back. The downstream O2 sensor looks brand new but the one that's in the header looks old. Cheap and easy enough, I just ordered a new one from Bosch and put it in. Now the car won't start. Cranks fine, I smell fuel under the hood when I try and start it. Checked fuses and don't see anything blown. I put the old o2 back on just to see and nothing. No start. Haven't really messed with it yet but did order a new starter relay, it was cheap so I'm starting there. Drove the car yesterday and ran like it always does, just fine.....

Do you think this is just a coincidence that right after I replaced the O2 I have this issue? I didn't think it would even matter if the O2 was plugged in at all for it to not start?

I didn't disconnect the battery when I changed it, would that matter?

Where should I start to look for my problem here?

Sorry for the life story, I'm just new to 420a motors so I thought it would help to have some back story.
Any suggestions appreciated, thanks!!!

 

[BLACK'98DSM]

It obviously has been running too rich. I'm currently wondering if the engine has flooded or if there is a fuel leak. Check the injector o-rings and the supply line to make sure no fuel is leaking. Even if the cylinders were flooding, you wouldn't necessarily smell fuel from the engine bay.

 

[Eclip97gs]

It obviously has been running too rich. I'm currently wondering if the engine has flooded or if there is a fuel leak. Check the injector o-rings and the supply line to make sure no fuel is leaking. Even if the cylinders were flooding, you wouldn't necessarily smell fuel from the engine bay.

Ok, I'm going to check, when I smelled fuel in the past I got under it a couple times and checked the lines but didn't see anything leaking, I will again today. How would I know if the cylinders are flooded? Pull a plug?

 

[1990TSIAWDTALON]

If you can, take out the O2 sensor, wait, hell, take out a random sparkplug, and post a picture. We all like "visuals" to help as best we can. A lot of us can tell you "something" about it with a sparkplug picture or all 4. Just a thought.

 

[Eclip97gs]

If you can, take out the O2 sensor, wait, hell, take out a random sparkplug, and post a picture. We all like "visuals" to help as best we can. A lot of us can tell you "something" about it with a sparkplug picture or all 4. Just a thought.

Ok, will do. I thought I would be home today at some point but it's looking like tomorrow when I get a chance to actually work on this thing. Thats for the advice so far.

 

[Eclip97gs]

Solved! It was just a coincidence, the fuel pump relay was bad and it just happened to be the exact same time I replaced the O2. Threw in a new relay and it's back running again! Thanks for everyone's help.

 

[BLACK'98DSM]

It's good that you were able to diagnose and fix the issue. If you played the game of guesswork, that would have been far down the list.

That still doesn't resolve the smell of fuel though.

 

[Eclip97gs]

It's good that you were able to diagnose and fix the issue. If you played the game of guesswork, that would have been far down the list.

That still doesn't resolve the smell of fuel though.

Right! I'm going to get under it to do the fuel filter within the next few days. The guy had a new one in the glove box when I bought it so I'm guessing it needs it. After the new o2 it runs better but still rich I believe, still getting not so great gas mileage. I also have some new ngk copper plugs and a new pcv valve I'm doing today just to do. It still dies sometimes just once right when I cold start it, dies, fires back up and runs... I do need to track down this raw fuel smell tho.