P0300 code....I'm running out of things to do

**boola1341** · 05-17-2009, 03:12 PM

This problem recently started and I'm running out of things to try. This is what I've done so far: Changed o2's, replaced plugs and wires, swapped sides with the ignition coils, replaced header gaskets with the gm gaskets and fixed small leaks in the exhaust. May I add that it's only running super lean on the passenger side, like 15 to 25 ltft's and up to 50 on the stft's on bank 2. Does anyone have any idea of what I should look at next.....fuel injectors on that side maybe????

**JoshieDoom** · 05-17-2009, 03:47 PM

Fuel injectors for sure. Find someone to log it.

**boola1341** · 05-17-2009, 04:58 PM

I visited gearchatter.com and that's the only thing I think it could be now.....damn fuel injectors. I even switched the driver and passenger side o2 just to see what happens.......stayed way lean on passenger side. I did noticed that the passenger o2 was really black compared to the driver side o2. Can I buy just 4 injectors or would it be a good idea to do all 4. And if I did all 8 should I keep stock ones or upgrade??

**JoshieDoom** · 05-17-2009, 05:06 PM

Originally Posted by boola1341

I visited gearchatter.com and that's the only thing I think it could be now.....damn fuel injectors. I even switched the driver and passenger side o2 just to see what happens.......stayed way lean on passenger side. I did noticed that the passenger o2 was really black compared to the driver side o2. Can I buy just 4 injectors or would it be a good idea to do all 4. And if I did all 8 should I keep stock ones or upgrade??

Depends where you want to go with the car. I would buy 8 used ones and have them flow matched at like new era performance IMO

**Frost** · 05-18-2009, 07:13 AM

Seems like I replied to this but maybe on a different board.... It's NOT O2s.

Why buy 4 new injectors? Why not swap the ones you have from left to right and see if the problem moves?

**DrMilhouse** · 05-18-2009, 09:24 AM

I pulled my MAF and cleaned it, it was FILTHY covered in black all over all of the sensors in it. After I did that, I have driven about 100 miles and haven't seen a P0300... this was just done a couple of days ago, but I was throwing P0300 every 10 to 15 miles.

**thepollock** · 05-18-2009, 09:27 AM

Have you checked for vac. Leaks? If you fined out its is a inj. Problem I would do all 8.

**boola1341** · 05-18-2009, 04:06 PM

My problem has been solved. A member on ls1tech told me to check the fuel injector connections for corrosion. So I pulled the four off on the passenger side then cleaned them and now it runs the way it should. I can get some sleep now. Thanks

**Frost** · 05-18-2009, 06:28 PM

Nice, glad to hear that you found it!

**Stephen Griner** · 05-20-2009, 01:22 PM

Originally Posted by Frost

Nice, glad to hear that you found it!

Frost is of most help! I still appreciate that info you gave me on the rpm wall I was hitting after my cam swap!! I have been having trouble with p0300 as well I may try and clean the wires to see if that helps, otherwise I will have to check the injectors themselves. Everything is great with the tune and the normal p0300 problem from a cam is tunned out and it still comes and goes. Weird.