Ok, I just installed a 50-trim kit along with 750cc injectors. I am having a problem with the car dying when i disengage the clutch. The RPM's will drop to < 500 and will sometimes stall out completely.

I also cannot seem to make any changes to my fuel trims. I am changing injector scaling and latency and my STFT does not budge from 50%. I believe this is having something to do with the stalling. I am also idling around 16:1 - 17:1 on my wideband, but WOT pulls are not lean. The car drives and idles fine, its just the transition from gear to neutral make the car bug out.

I have attached a log of this happening. You can also see my fuel trims. Scroll down to row 240 to see the transition from 1st to neutral. You can see the RPM's and Voltage drop significantly. Any ideas?

 

please help...i need to address this issue today

 

Well, without looking at your log and just going by your comments and some experiences that I have had, I can try to help a little.

1. Was this a BB turbo by any chance?

The only reason I ask is because years ago when these BB turbos were new on the scene, everyone was upgrading to them, including myself on my old Eclipse. A lot of people with a Mitsu Karman MAF were having the stalling issues that you are explaining here, including myself. DSMLink gave us the ability to adjust and scale the airflow tables, which seemed to help with some people. My solution was to go to a GM MAF in blowthrough, which completely solved the problem. Basically, I think it has to do with the BB turbos spinning so freely, even at idle, or when getting on the gas and then off, that it creates a higher than normal airflow at that time, which needs a lot of fuel adjustment. If this truly is the problem (may only be part of yours...I truly think that you may some air metering issues or injectors scaling problems), then there won't be a lot that you can do with ECUFlash at this time. The best you could do is scale your injectors and latency values until your idle and stalling issues are overcome and then adjust the rest of the map accordingly.


2. You stated above that your STFT is pegged at 50%.

Well, that right there is basically showing you your problem. There is too much airflow, or too little fuel, for your fuel trims to compensate for. So, either your injectors are scaled way too small, or you aren't measuring all of the airflow.

You don't have a VTA BOV do you? Are you sure your BOV isn't leaking and you don't have any boost leaks, etc? What did you scale your injectos to and what latencies did you use for the different voltages? What did you try to scale to in order to fix the issue?


So, these are the steps that I would recommend, from easiest to hardest:

1. Are you running a VTA BOV? If so, recirculate it or put the stock one back on.
2. Is you BOV leaking or adjusted improperly? If so, fix it or replace it.
3. Do you have any boost leaks? If so, fix them.
4. What are your injectors scaled to? If scaled to stock, scale larger and adjust latencies until you see some results with your fuel trims. You need to give the ECU the maximum adjustment range that it can use, just in case point #1 at the top of this post is coming into play. Keep in mind that if you make progress at idle, any scaling adjustments must be accounted for in the rest of the fuel map. So, the rest of the map will have to be adjusted, too.


Basically, one or a combination of those reasons is causing your issue. The way to see if you are making progress is by your fuel trims. Always log them and once they start changing for the better, you know what you just did made some progress.



Eric

 

Neutral only? Some settings are set there, like cold idle

 

I will try adjusting cold idle and see if that helps

The turbo is ball bearing. I am recirculating my BOV. I removed it and my MAF pipe and reinstalled them to try to ensure that there were no leaks and everything was in there properly. That didnt seem to help. I dont have a way of testing for boost leaks, but I am going to put together a boost leak tester ASAP.

I did accomplish one thing on Sunday, I got my STFT to log at 100% after a full day of driving. The injectors I had ordered were labelled PTE on the site I ordered from, so I thought I was running PTE's. I had tried scaling anywhere from 620 - 715. I got down to the point where I was going to reinstall my stock injectors and go from there. When I went to the car to take out the larger injectors, they were engraved with "FIC". So, I searched the forum a little and founf guys that were running FIC injectors had them scaled to the actual injector sizes. So I tried a scaling of 750 and that has yielded me my 100% STFT, but has not remedied my stalling

So, as of now my long term and short term fuel trims are both at 100%. But my middle trim reads 68%. Not really sure why or how that would effect this stall issue.

I will play with this some more and mess with the cold idle settings to see if that works.

Also another thing to note, when I had my XEDE, Shiv told me to adjust my idler screw after I had installed my cams to bring back some vacuum. Now I am reading that adjusting that screw can mess up your fuel trims. I feel that might hae something to do with this issue as well.

 

promblem resolved...

After I got my fuel trims worked out and was still having the same problem, I made some changes to my ISCV tables. This seemed to have solved the problem almost completely. I still have a little fine tuning I can do to make it perfect, but I am glad to have the issue worked out

Thanks for the help guys.

 

Good work. It's nice to see that changes in the ISCV settings can resolve this problem. I think that's good news for others that may be experiencing similar problems and couldn't fix it another way.

Perhaps you can share your settings for others.


Eric

 

sure...here is my intial table with AC off in Drive from -32C to 87C respectively

255
174
144
132
111
93
34
18

here are my new settings...basically I just bumped the entire table up a tad

255
177
147
135
114
96
37
21

Here is the same table in Neutral...OLD:

162
148
139
130
112
85
30
24

NEW:

165
151
142
133
115
88
33
27

I also bumped my idle up about 100 rpm, but I think the ISCV tables are what really remedied the problem

 

Good data, thanks.

I think bumping up the idle helped more than you think, though. An interesting test would be to put the idle back with the changed ISCV settings.


Eric

 

i will have to give that a shot when i am trying to dial it in better

the only reason i say that is b/c I had my idle up to almost 1200rpm at one point and still was having problems...i moved it back down to 93x, but now have it around 1020

 

What is ISCV btw? The numbers I have in mine are way different then that on the 9. Even coming off stock JDM flash's. Kinda weird.

 

ISCV is Idle Speed Control Valve..

Actually if they open up too much, or too little when idling, it will swing back and forth in your afr's before the trims can get a chance to compensate in closed loop.. I get this pretty frequently since the stepper sometimes resets to a new position according to these settings..

Its pretty obvious when you turn on your A/C, you'd see if momentarily swing lean until the trims catch up.. if you get the settings down, it won't do it as dramatically.