Thread: AFR goes up and down 10-14 after turbo install. Need help tune going to sht

HOORAY!

It finally fixed itself!!. It's running at 15.1-14.7 on idle and I did it all by myself LOL

I fixed it by actually driving the car for 20+ minutes, revving it a little and fully warming it up. Oil pressure gauge reads correctly now too.

on a sidenote what speed will I be at 4th gear 6k?

^ about 95mph

Originally Posted by Splash45

^ about 95mph

That's about killa LOL so i did it 3rd.

Here is my log


For some reason I am running lean at 3k-3.5k I think turbo kicks in hard so I need to add fuel write?
i'm running 255pump n 527 injectors already and didn't think I need to add
Also

To prevent drift tune, I was told to reset the ecu/reset the fuel trim BUT I already did a tune before I reset it. after I did the reset the previous tune ran a little lean.
Is it suppose to change my tune if I reset the fuel trim?

Bring it down to 11.0 to be on the safe side since u dont have a reflash

Add 6 at 3008
Add 3 at 3449

And add 2 til redline. That should put u at 10.8- 11.0

To make the graph more easier to read just have the afr rpm and tps on screen.

Thanks a lot Splash45, I just did a retune and most point are running at 10.9-11.0. Time to look for a dyno day . I hope i hit at least 230 on 5 psi

n.p now you should do the low throttle

Originally Posted by Splash45

n.p now you should do the low throttle

I thought low throttle was auto tuned by the ecu?


Anyways while driving home from the highway my tune went to shit and I did not even notice until I did a lot of pulls. it was at 12.1. After i resetted the ECU it was doing 13.2 full throttle and didn't push it anymore.

Then I saw smoking from the engine bay and popped it open to see coolant everywhere????....

Why is my tune going to hell? The only thing I can think of is the 6oz of fuel system cleaner I dumped in yesterday. Could 6oz mixed with 10 gallon really change my tunes?

You can tune low throttle to zero out fuel trims and prevent tune drift.

Any idea where the coolant came from?

Originally Posted by MisterNuts

You can tune low throttle to zero out fuel trims and prevent tune drift.

Any idea where the coolant came from?

I think the low throttle fuel trim drift is fking me up. Especially 6th gear half throttle when it stays on 14.

Coolant came from my coolant cap and it went everywhere.

BUT even when I resetted my ECU my AFR was still lean.

How do I tune low throttle? head is messed up right now.

Just afraid that i might of messed up my engine because of the lean pulls especially when coolant start exploding.

yeah, i probably wouldn't be boosting that thing.

there's obviously a problem somewhere. tuning via safc, right? are there any exhaust or vacuum leaks? 5psi shouldn't make you pop a headgasket, but it sounds like you've either boosted the headgasket into oblivion, or you're getting mad amounts of coolant blowby. hopefully you've been letting the car warm up until operating temp, and then making sure your oil is at least within the correct heat range for boosting (think it's about 185 degrees or so).

quite a bit of misinformation in this thread. you can't tune your low throttle settings unless you unplug your primary and secondary o2 sensor. if not, the ecu will just correct the changes you've made via the o2 sensor, and still try to retain stoich 14.7 at idle and low throttle. any changes you make can negatively effect that unless you run without o2 sensors (running in open loop all the time), which is also not great for your engine and will cause stupid problems with lean/rich spikes and overall pitiful drivability.

you shouldn't have to pull that much fuel, even with 527's. with 440's on a 57 trim, i was only pulling 5-7 points across the WOT range, and slightly more from 3k-4.5k, putting me right at 11.5 @wot.

also, the reason why you're staying at 14 in sixth at half throttle, is because the ecu doesn't know what's going on. it still thinks you're driving an n/a car, so it's trying to keep you at stoich while cruising and idling. unless you do the boost hack mod, you'll never be able to roll into boost part throttle with an safc or similar product. it's just the way it is, because it can't read anything other than rpm points and fueling. so trying to part throttle boost is going to fuck your shit up with the safc.

i dn't think the low throttle fuel trims are your problem. i drove my car for 8 months and never touched the tune on it, and every time i rolled into boost, it was a consistent 11.5, and when the tune would drift, it would only drift either high 11's, or high 10's, never back to stoich or in the 13's like you're saying. and you wouldn't have to reset fuel trims every time you drive it, so there is definitely something else wrong.

if you've pushed enough coolant to fuck the head up, you've already done enough damage to your shit.

what year is this car, how many miles, other mods done? tuning via safc/safcII/neo/bucket of dicks? how new are the o2 sensors, mainly primary? still on stock maf?

02 85k with I/H/E, colder sparks, light weight pulley. It's tuned on a SAFC2 with the help of a wideband.
I have no exhaust leaks and it doesnt seem like I have a vac leak. It idles fine and such but once full throttle the AFR numbers go weird.

The 2nd o2 sensor is stock but the primary is a new bosch. Still on the stock MAF.
If partial throttle boost will fuck your sht up how do people drive on the highway in 6th gear going 60-70s? Or when you downshift from 6th to 4th?

That's the only thing that came in mind when I saw coolant everywhere

I nope i didn't fk up my HG but I didn't get to check on it when I got home. I'll break open and check the plugs and lines.
Tune wise, I'm only pulling 2-4 fuel points from 4k-6k.

I make sure to warm it up before I drive but I don't know If it gets to 185 degrees.

lol

cruising in 6th gear at 60-70 wll be nowhere near boost. you'd have to. going way faster than 60-70mph to build boost, that's like half-3/4th throttle in sixth to hit boost. you should be pulling anywhere between 9-15inHg vacuum at 60-70 in 6th gear, not boost.

lmao, ok I see so that might not be going into boost. Steady it's at 20 so I thought if it's 9-15 it would go into a little boost.

fearing the worst LOL

Ok, head gasket is leaking pressurizing my coolant sytem. Coolant flowed out of radiator with the cap off when I started up the car.

Honestly I knew it was going to blow being a 02. It was having H/G symptoms days after I bought the car.


NOW what I want to know is will a leaking head gasket/ exahust gases flowing into the coolant cause my engine to run lean? hopefully it's this

or did running 13afr lean pop my head gasket? if so why did my tune climb so high.