Running Lean.

[intimdatr]

Alright some of you all that follow the Facebook groups have been some background on the issue, but as I know most aren't I'll start from the beginning with a hope of getting everything in one place to help simplify some of this.

Background on the car: PnP ntake and heads, BBBs, UDP, 80mm MAF, LPM, X2J, +20 cams, 160k on the motor. (Couple people asked already about a CAI, NO. Stock Box)

Car is idling and driving at 16-17:1 and sometimes even as high as 18:1 AFR. The typical response is going to a vac. leak, I can not find one at all with start fluid, I have checked where the intake connects to the heads, all the joints and hoses, nothing. I have pulled off the hoses and caped the ******* on the intake with no change.

I changed back to a stock 55mm maf, made zero change in the AFR. Unplug the MAF and the car runs super rich but does idle at the 14.x:1.

I pulled a plug and it is white as can be, so the wideban is correct and has been calibrated twice.

Car has good fuel pressure checked by a gauge.

Car will richen up the higher the RPM is, 13:1 at WOT 5500 rpm+ so the problem is likely sensor based as many are not used during WOT.

Changed Map sensors, no change.

Has a new-ish cam and crank sensor in it.

Has a 10-20k O2s (Bosch)
pulled the IAT sensor, no change but it does throw a CEL.

Car has no CEL at all even though its running at 16-17:1, which should be enough to throw a full rich mixture code, which is odd.


So thoughts? I cant hook up my tweecer and data-log due to having issues with something going wrong when trying to upload my 80mm MAF file to the tweecer, if someone can help with that, I can then data-log and have more knowledge.


I'm pretty much at the end of my knowledge on this. Thoughts?

 

[jimtash]

Change out the coolant temp sensor. Buildup on the sensor probe will wreak havoc on the fuel trim tables.

 

[intimdatr]

Is that the one that is on the back side of the silly coolant split thing on the driver side of the motor? (like a 4 lug connector?)

 

[jimtash]

Yep, beneath the throttle body. Not expensive either but very crucial to engine operation.

 

[intimdatr]

Yep, beneath the throttle body. Not expensive either but very crucial to engine operation.

Shall check that put tomorrow, 6 degrees outside right now.

 

[intimdatr]

Well changed out the ECT with no change. Looks like all the easy stuff is done. Time to start back pining stuff.

 

[sperold]

Install another Intake Air Temperature sensor, all the symptoms point to something wrong with your air diagnosis. Since it is cold outside, the A/F mixture should be rich, at least in the very beginning. There is usually as code when it is out of range, but who knows. The only time I had problems with one is when I "cleaned" it, big mistake.

 

[intimdatr]

Changed iat as well with change. On cold start up (open loop) its rich but anytime it's in closed loop it is lean

 

[shomethe$$$]

so any luck on figuring this out? a few more questions, don't both the LPM and tweecer use the EEC J3 port? I'm going to assume that you do have the tweecer connected to the J3 port and your not using the LPM. My first question would be is the tweecer able to read the EEC? are you able to write a tune even if its the base X2J one?

Stepping back a bit. You do know in tweecer, I use the Calcon program that it came with, you can't write exact values, you have to use the arrows in the value box, so it will get the next value allowed. Like you can't write .43 volts @ 12.5 kg/hr, the program will only write it as .42993 volts and 12.259 kg/hr. Also you should use the standard 30 point transfer function.

I would sort out the tweecer issue and then start with a base X2J tune. When you say 80mm MAF, which one exactly, they have half a dozen. I know I've use the Lincoln Mark VIII one before and its different from certain years 94-95 & 96-up, I posted that several years ago. I wouldn't load any of those just use them as a reference, start with the 55mm SHO stock MAF one and richen it where you need it.

About running lean, I would do a compression test and hope that you don't have a leaking valve. As for using starting fluid, sometimes you can't get under the hoses, so I just put my hand on before the MAF, if it stalls right away then you shouldn't have a leak. If it tries to stay running you have a leak. I haven't cammed a SHO but have a honda before, and no matter what idle quality is going to be lean since those were designed to run over a certain rpm. So you may want to contact Shonut and ask him if the idle needs to be enriched.

A few other tests, check your idle charging voltage with everything running, and make sure the UD pullies are not under charging. I would also take out the wideband until you sort out the other issues, unless its the only way to get your readings. It will ruin it. It would be better to get the tweecer running right. Make sure your secondaries are closed at idle. And don't run WOT until you sort out all the other issues. Just a thought.

Also post a link to the facebook groups.

 

[intimdatr]

Haven't had a whole lot of time to mess with it since having to go back to school.

I havent messed with tunning the car at all yet, I juts got my wideband hooked up saw it was running super lean have been testing ever since, until I left for school and she is sitting at home. The tweecer reads and write everything fine but the MAF stuff is being weird. Ive been using calcon as well since i havent got the coin for BE currently.

Im running the LPM currently due to when I'm using the Tweecer and input the MAF curve from SHOnuts website for the 80mm Mark MAF. I load it and then I will read the tweeecer again and it will show some SUPER weird curve that isnt really a curve and has weird spikes all over the place. Im using a 80mm Mark 8 maf from a 96-98 car with the OB2 stlye plug with a solder on pig tail to convert it. I may try the tweaking the base MAF curve then, I like that idea much better.

The Idle charging voltage is good,low 14s to high 13s for voltage depending on what all is turned on, the idle is bumped up so so it negates that enough that it doesnt effect much.


Edit: Im going to be swapping out O2s this weekend in last ditch effort to double check just raw sensor failure.

 

[shomethe$$$]

Oh I've had that issue before with the spikey read, I can't remember how I fixed it, if I recall I went from the 30 point X2j to match the Lincolns Mark VIII function, but I'm assuming something is not consistent with the loaded MAF and the X2J stock one. Or I selected the wrong strategy. Or maybe I forgot to uncheck "Update". So its just easier to use the X2J and save it as a new name once you changed all the values. Unless your using the Lincoln injectors I don't see any point in using it, only as a reference and starting point. Report back.

 

[sperold]

I has some bad luck with a Bosch O2 sensor, but mine would turn on the CEL light when my RPM dropped below 2K, so that may not be it. I think sometimes they get dropped in shipping or mishandled during installation, and act up.

 

[intimdatr]

Good to know its solve able, I'll look more this weekend.


Yeah they are Bosch O2s but they have like 20k miles on them so IDK, i had a wiring harness fail on me and I wonder if it took them with it. I have a pair of NGK OEs laying around so they will be going in as a JIC.