Engine Running Badly - Please Help!!

[V10Venom]

Well it's my girlfriend's car but it's been to three places for diagnosis and no one can figure it out. We've heard everything from the catalytic converter to the fuel injectors to the spark plugs. Hopefully someone on here has had a similar problem that can help us out. After taking the hypertech tuning off a code came up that was this:

Code # PO 440
E-Vap Code
Evaporative/Emissioni
Control System Malfunction

Here's what I've noticed after driving it. It drives perfectly fine when first driving. It drives fine when you get on it. But under normal driving conditions it starts to feel as though it's missing. You can hit the gas and it will feel like it's stuttering almost. But not badly. If you listen to the exhaust you can hear a popping noise that occurs at every 8 seconds and it happens again 4 seconds after that. Then it happens again in 8 seconds and again 4 seconds after that. And continues on that way. It feels slower but not dramatically except once in a while it will bogg.

After being in the shop for a week they thought it was fuel injectors so they flushed them and now it's running slightly better. You can still hear the noise coming from the exhaust but it's not as bad and doesn't happen as often. They are saying it's the fuel injectors but would that explain everything that is happening?? I don't feel like dropping $500 on something that may or may not be the solution. Can anyone give some friendly advice?? Thanks!!

[s.reef]

Just to be safe I would change the plugs and wires...my old car ran really rough and it needed new plugs and wires....worth a try.

[00firebird]

do the plugs/wires yourself its like 50$ for the parts, see if that fixes it, if not i guess u can go with the injectors.. if it is a fuel spraying issue i guess it could be making noise every 8/4 seconds. i have a bad cat and theres rattling in low rpms and popping/backfiring if i back off the gas in the upper rpms.

[WMCCjames]

A poping noise in the exhaust generally is a spark related problem. It's unburnt fuel lighting off downstream. I cracked a plug on my LS1 and it did that very same thing...you could almost time the pop noise it was so consistant....but the PCM also gave me a cylinder misfire code which it sounds like you haven't experienced that.

[JoeliusZ28]

try unplugging your EGR valve. if the problem disappears, youve found the culprit.

*edit* it might not be as simple as just 'unplugging it,' im not familiar with LS1 emission equipment. my truck had a 1500 rpm sputter and i just yanked the EGR vacuum tube and the problem was solved.

[WMCC Gary]

do the plugs/wires yourself its like 50$ for the parts, see if that fixes it, if not i guess u can go with the injectors.. if it is a fuel spraying issue i guess it could be making noise every 8/4 seconds. i have a bad cat and theres rattling in low rpms and popping/backfiring if i back off the gas in the upper rpms.

If you can buy good Plugs and Wires for a LS1 for $50, I want to know where. The Cheap crap is $75 at the zone.

[meissen]

I can bet that it's the EGR valve. That sounds 100% exactly what was going on with my car when my car started acting up. It started with random bogs, random popping noises, car just wouldn't feel as fast. Then all of the sudden BAM the egr valve got stuck entirely and it SUCKED ASS for idle and driving at all.

I had the EGR valve removed all together. I notice that my car's SES light doesn't come on until after the car has warmed up AND when driving normal. It doesn't come on when I first start it, and it doesn't come on until I lay off and "cruise."

I bet its the EGR.

[lozanoa11]

get rid of the egr and evap system.

[archemedes]

evap is the canister, you may have a bad or leaky solinoid. There is no reason to pull the emissions stuff off, especially egr and evap, neither one takes away power (egr doesn't work at wot) when you get a code, start with the system the code points to, egr has it's own codes

[greenmachine]

I can bet that it's the EGR valve. That sounds 100% exactly what was going on with my car when my car started acting up. It started with random bogs, random popping noises, car just wouldn't feel as fast. Then all of the sudden BAM the egr valve got stuck entirely and it SUCKED ASS for idle and driving at all.

I had the EGR valve removed all together. I notice that my car's SES light doesn't come on until after the car has warmed up AND when driving normal. It doesn't come on when I first start it, and it doesn't come on until I lay off and "cruise."

I bet its the EGR.

speaking about that brian, shoot me a pm sometime when you got time on the process of removing the egr... mine has been throwing a code, not messing up yet but if it does i would like to know how to get rid of it..

[V10Venom]

Well it's definetely the injectors from the walmart special gasoline. Can anyone give me some information on where to get good fuel injectors?? They're going to charge her $1,000. Is that about right?? Any tips to do this for cheaper??

[WMCC Gary]

Well it's definetely the injectors from the walmart special gasoline. Can anyone give me some information on where to get good fuel injectors?? They're going to charge her $1,000. Is that about right?? Any tips to do this for cheaper??

Change them yourself.

[Lucky SOB]

Try some "Lucas Oil" fuel injector cleaner first, its only $5, might help and its a lot cheaper than new injectors.

[V10Venom]

Try some "Lucas Oil" fuel injector cleaner first, its only $5, might help and its a lot cheaper than new injectors.

They've been flushed and were still bad. Now they're taking them apart and cleaning them by hand. Here's the thing...Nicole owns the car, makes the payments, etc. but here dad won't let me touch the car. Anything that gets done to it has to be professionally done. If they have to be replaced I'm hoping I can find her a used set on here or ebay. There's a set on ebay right now for under $100 with the rail.

[greenmachine]

theres a couple of people on here that are certified if i remember right...

or... what daddy doesn't know wont hurt him