Possibly running rich, backfire but pulls hard

[Brunoboy]

Mods again are:
fuel lab fpr
evo viii injectors
evo ix fuel pump
evo fmic kit by jon vr4

head:
rebuilt with bc valvesprings and retainers

block:
bse
mls hg
arp headstuds


bolt ons:
dsm gt high flow manifold
mhi b16g
2g o2 housing
2.5-3" straight pipe
hks evc boost controller
2g maf with hard intake pipe

electronics:
boost gauge
egt gauge
oil pressure gauge
keydiver chip

well before my timing was off so i had it redone, the knocking still happened and was running pig rich, just recently changed the coolqnt temp sensor because it read -4 degrees , now im boosting 16 psi with 6 counts of knock and 19 psi with none, he sop i took it too ran it on the dyno before i chaned the temp sensor and it was 9.x afrs all day. Now it seems normal just wondring if backfire was normal.
-shane



dsm gt high flow manifold

 

[Brunoboy]

Bump

 

What do your plugs look like?

What heat range plugs are you running?

What gap are you running your plugs at?

Take a picture of the plugs close up and post it on here for me to look at. I am leaning towards them being bad, but running that rich probably has something to do with it. Just want to check the basics first.

 

[Brunoboy]

They are brand new,
bpr7es gapped to .026 bwcause .028 was misfiring like crazy, we tried new plugs and new coils and new transistor as well, nothing helped the situation.

 

Sounds like you need to tune your car. If you are in the 9.x AFR range then you need to lean that car out. I would dail in the afrs and see if that cleans up the backfire and the knock.

Post up a log of what is going on.

 

[Tre3zy]

i have a logger and all, just dont know how to post it. and what should I log?, my AFPR is turned lower than what the chip was supposed to be at, only boost leak, found was at the TB shaft seals, but it shouldnt affect it that much. I am getting to the point where I might as well buy Link to try and fix the issue.
-shane

 

[AnotherNewb]

Quoting brunoboy:
Mods again are:
now im boosting 16 psi with 6 counts of knock and 19 psi with none, he sop i took it too ran it on the dyno before i chaned the temp sensor and it was 9.x afrs all day. Now it seems normal just wondring if backfire was normal.



And now its normal with no back fires and normal AFR's after the temp sensor change?

 

I'm not a big fan of AFC's but do you know someone that has one laying around that you can throw in and lean it out with that. It should fix your problem, but you should get something that's build for turbo cars for a permanent solution.

 

[Rausch]

Quote:
well before my timing was off so i had it redone, the knocking still happened and was running pig rich, just recently changed the coolqnt temp sensor because it read -4 degrees , now im boosting 16 psi with 6 counts of knock and 19 psi with none, he sop i took it too ran it on the dyno before i chaned the temp sensor and it was 9.x afrs all day. Now it seems normal just wondring if backfire was normal.

Temp sensor thought it was -4 and was loading it up with fuel?

 

[Brunoboy]

Temp sensor is new and runs better, but still rich as heck. I have no idea

 

If you have no way to lean it out, I would try a little hotter plug.

 

[Tre3zy]

hey shane wait dont you have oversize valves on that thing? is that gonna make a difference?

 

[Brunoboy]

I have no idea what size valves are in it, I dropped it to tony and called it a day......lol, And a Hotter plug as in?

 

[AnotherNewb]

What are your fuel trims? Fouled O2 sensor from running so rich?

 

[Tre3zy]

yea i thought about the o2 sensor as well.... might wanna change that

 

[Rausch]

Quoting brunoboy:
I have no idea what size valves are in it, I dropped it to tony and called it a day......lol, And a Hotter plug as in?

One number less on the NGK plugs= 1 heat range hotter. 6's= stock, 7's= std upgrade, good for boost pressure over stock. 8's= Big boost. The 'colder' the plug, the easier it is to foul.

 

[Brunoboy]

The o2 sensor has less than 1000 miles on it, and yea i had standard plugs that missed even worse.