Car spontaneously getting Lean/Rich...

[The Rock]

I'm having to re-tuning my car, long story short had a shop tune it and the tune was awful knock throughout the rpm range, surging idle to continuous stalling.

So needless to say I never used HPtuners and I am diving in head first and trying (note trying) to tune my car myself and rectify what was going on. I have finished getting rid of the majority of knock and got my idle where it wont die anymore or surge.

Well to get back to my main issue, the car usually reads 14-15 AFR on just cruising and normal driving. WOT the car gets RICH so rich to the point I can smell gas at times and my wide-band doesn't go that low (10.0 and lower). Also if I gradually roll into my throttle the car bucks and suppers as it reads immediately rich. Just driving along it will run fine but then go as lean as 20.0 AFR.

So my request is can someone look at this tune and maybe point me in the right direction as to what I need to do to rectify these issues (ie rich, lean conditions).

Any input woud be greatly appreciated and all mods are in my sig.

"Christina" 2006 SRM (1 of 369/A4 & 1 of 1/A4 w/418ci)

Performance/Misc:
TSP 418, Trickflow Heads, FTI Cam Package, JB Catch Can, FTI P/P FAST 90, FAST FRs, (Modified)HARDCORE CAI, KOOKS Stepped LT, Yank 4k, Transmission Physician Tranny, Borla CB, LPE Oil Pump, 45# Inj., SLP Pulley, LPE Fuel Pump, Drag Bags, King Springs, PLX WB,

[The Rock]

Anyone?

[flea]

Several questions (I haven't looked at the posted files).
Are you running the car in open loop only?

Speed density tune or MAF?

For WOT AFR tuning with a WB try setting the IVT gain table from 147F up and 85 kPa up to 0.100 (like in the attached table). This will eliminate one more moving target for the fueling as the ECM will use the richest value for the conditions (PE or open loop)

[flea]

After a quick look at the tune ......

Also disble the the master post O2 test and put all the DTC/SES settings back to stock for the O2s and catalyst. Based on my experience I suspect there is a lot going on with emissions related items we are not directly aware of that have strange effects on the fueling.

[flea]

Change the PE enable MAP setting back to the OEM (15 kPa) value as well.

If you are using the MAF, put the values back to stock and start over as they are totally screwed up. They should still resemble the smooth, linear stock OEM line (only vary in scale based on the AFR). The MAF table could account for MOST of craziness you are seeing.

Bottom line, it looks like you might be better off starting over (the VE table is suspect as well at this point) as you are trying to troubleshoot far too many variables here.

[The Rock]

Thanks Flea I appreciate it. As far as emissions I don't have cats anymore and my rear O2 should have been deleted, so I will put the settings back to stock as you recommended.

I am currently using my MAF now you say put them back to stock and start over. Well here is where I am stuck, I was looking at the VE table and MAF tables but my question is how do these tables get populated? As I am not sure how or what to enter (if any) type of settings in there.

So would I just load the stock MAF table up then what?

Sorry for the basic question/s but I literally just started using HP tuners yesterday.

[RWTD]

I'm working on building you a tune. But I have a question: Who makes the injectors you have? Can you please get me the part #s and where you got them from?

Also, I'm not trying to be hard on you when I say this, and quite possibly a lot of this "hacking" in your tune came from the previous wannabe tuner shop, but your spark tables and PE table absolutely scared me, as well as many other things in the tune. We really need to start over here.

[The Rock]

I'm working on building you a tune. But I have a question: Who makes the injectors you have? Can you please get me the part #s and where you got them from?

Also, I'm not trying to be hard on you when I say this, and quite possibly a lot of this "hacking" in your tune came from the previous wannabe tuner shop, but your spark tables and PE table absolutely scared me, as well as many other things in the tune. We really need to start over here.

Thank you I really appreciate it. And yeah that tuner/tune is totally screwed.

As far as the injectors they are 45# Siemens I dont have a part number for them (unfortunately).


Once again thank you for your help I really appreciate it.

[FraggerCrue]

I'm working on building you a tune. But I have a question: Who makes the injectors you have? Can you please get me the part #s and where you got them from?

Also, I'm not trying to be hard on you when I say this, and quite possibly a lot of this "hacking" in your tune came from the previous wannabe tuner shop, but your spark tables and PE table absolutely scared me, as well as many other things in the tune. We really need to start over here.

RWTD, I've been trying to help clean up this mess. We went up to Tony Gonyon's shop over the weekend after I gave up. I kept finding things that made me say WTF??? I'm not a tuner, not by any stretch, but I know enough to be able to look at a tune and see obvious problems. The tune you saw, I believe, was after we cleaned up portions of the spark tables so that he wasn't getting constant knock. We did not touch PE, VE, or MAF tables. We did make some minor changes to an idle table.

We had the car on the dyno for several hours. Tony is a Ford guy, first and foremost, but he has tuned a few LSx cars. He cleaned up the MAF tables. The Rock and I had already pulled a lot of timing out, so we didn't really have any problems with knock. Unfortunately, cleaning up the PE table and the MAF tables only made matters worse on the street, because the VE table was so bad. You should have seen the A/F bouncing back and forth from 10.0 to 20.0 just trying to cruise down the road. If we'd had more time Tony could have worked on driveability, but by 7:30 at night they had already ticked off both of their wives.

I saw things in the tune which I didn't even understand why they were changed. If I were to try to work on the existing tune, I would want to go through very carefully comparing it to a stock tune, just for the purpose of checking things that normally wouldn't need to be addressed.

If it helps, The Rock can send you the tune from Saturday when we left the shop. The Rock's wideband agreed with Tony's wideband, so you can trust that data. As for WOT, the car runs like a scalded goat(?). I would want to tweak the MAF tables and maybe the PE at the track, but that tune was pretty much on the money for WOT.

Just so everyone is clear, I didn't tune this car and Tony Gonyon did not tune this car. Trying to observe etiquette, the tuner has not been named, nor will he be, I believe. Thanks to everyone that is helping out (Flea, RWTD, Tony, etc.).

dk

[FraggerCrue]

I was looking at a Daytona Controllers dual wideband installation instructions and they had some interesting information. Here is quote:

Excessive exhaust back pressure. Wide-band
sensors are affected by back pressure. Excessive back
pressure causes exaggerated AFR indications under
rich and lean conditions, but has little effect at 14.7
AFR (stoichiometric). Race vehicle exhaust systems
are free flowing and problems with exhaust back
pressure are not likely.
Exhaust reversion. Reversion is the term for a
negative pressure wave that can suck ambient air back
into the exhaust and cause an erroneous lean AFR
indication. Open “drag pipes” usually suffer from
reversion effects and may not be suitable for use with
the WEGO IIID except at or near wide open throttle.
Reversion effects will be most noticeable at idle, part
throttle low RPM, and decel.
Excessive scavenging. Tuned exhausts in
combination with a high overlap camshaft profile can
pull unburned air and fuel mixture through the cylinder
into the exhaust and cause an erroneous rich AFR
indication. The same effect can occur with high boost
turbo/supercharger applications.
Misfiring. If the AFR is so rich that the engine
misfires, high levels of oxygen will remain in the
exhaust gas and result in an erroneous lean indication.

I think that super lean condition we were seeing on the dyno at initial WOT was a true lean condition, however, because adding fuel corrected the problem. Just interesting things to keep in mind. Especially the bit about cats and the bit about cam overlap. The overlap issue is why, in race applications, it is often better to look at exhaust gas temp.

[RWTD]

Guys, I'm out of town right now, and I'm getting internet to my laptop via my jailbroken iPhone on a non-3G network, so it's crapshoot at best.

For now, you should completely disable the VE calculation, and tune in and run solely off the MAF. We can work on the VE later, if you wish to use it, and once we get the rest of the tune perfected, but the VE re-enable is not necessary at all. To do this, go to Engine, Airflow, Dynamic Airflow, and set the High RPM Disable to 100, and the High RPM Re-enable to 0.

As for the exhaust and widebands and narrowbands, you're right, it's basically impossible to get an accurate reading on a system that has the cutout or open end too close to the O2 sensors and/or wideband.