Whats up with my A/F - PART 2

[SilverBullet00]

So, I am running lean. NOT as lean as my good for nothing wideband says I am, but lean. The tune with no modifications wasn't able to make a full run on the dyno. (14-15AFR)

I finally put the car on the dyno to check the AF like many of you recommended. Turns out we had to add 10% fuel just to pull one run. Finally @ 14% fuel added the car was safe. FULL THREAD HERE W/ DYNO SHEET

I finally got a response back from Tim. He said he has sent out over 1000 mongoose tunes, and has never had a problem with the tune. He thinks something wasn't installed correctly or their is a hardware failure. He is going to send me a new tune with fuel added....but I don't know what I could have installed wrong or what could have failed..

The ONLY thing I can think of, is I extend my MAF wires my 6-8" with crimp on connectors to make the MAF harness reach into the fenderwell better. Is there any problem with this?

I know I am needing to upgrade the fuel pump, but what other things could I have installed wrong or failed? Any suggestions would be greatly appreciated!!!



As far as the Wideband is concerned, I am going to try and get a senors this week from the VW dealership or autozone if they can get it here faster.. If that doesn't work I am getting something different..

 

[the98stang]

I know I am needing to upgrade the fuel pump...

Please tell me you aren't running the stock fuel pump...

If you are, that thing is mostly working at 100% duty cycle, creating the lean conditions.

 

[SilverBullet00]

No, I have the SVT fuel pump that comes with the mongoose kit.

I am thinking I am now going to try and run the Ford GT pump with the wiring upgrade to see if that helps.


Any other suggestions or tips??

 

[the98stang]

Well if you crimped the MAF wiring correctly that wouldn't cause the problem. The focus pump might be the main cause of the problem, but you never know with out data logging. This is why I don't trust canned tunes. I know Tim is a good tuner, but every car is different, and you can't make one tune work for every mustang with out some adjustment. Bottom line is, you need to datalog that car.

 

[SilverBullet00]

I am sure the MAF wires are all right, I just wasnt sure if them being extended would cause some sort of latency and mess the readings up. I have datalogs, but the all seem alright?

Tim said something about the MAF being installed in the right direction... is there a certain way you have to rotate it? Or was he being a wise guy and meaning backwards?

 

[twogts4us]

What kind of MAF? It's pretty hard to get an OEM MAF backwards, but some aftermarket ones will look more or less the same, frontwards or backwards. It would definately cause an issue if it were in backwards.
I'd redo your MAF extensions just to ensure that is not the issue. Solder and heat shrink each connection. (My theory here is that the MAF doesn't operate as an ON/OFF switch, but with variable amounts of voltage. If there is shoddy wiring or connections that are causing incorrect readings, then your AFR could very well be off. There may not be an issue, but you can eliminate this as a possibility by redo-ing it to be sure.)
DO you have a FP gauge? What's your FP when you go lean? Have you datalogged while on the street (as opposed to on the dyno)?

 

[SilverBullet00]

Yes, I have street datalogs. Its really hard to look at all the gauges at once and drive, but the FP I believe is 55-60psi @ WOT.

I have the lightning MAF, I think its impossible to install backwards, but I was wondering if there was a certain way to rotate it..

Tomorrow I am going down and getting a new wideband sensor. Right now, the gauge will dip down to the low 11's during WOT, but around 3500rpm's it just pegs the gauge lean.

 

[SilverBullet00]

Frickin Autozone wanted $ 90 for the bosch sensor... I called Advance Autoparts and it was only $ 51 there!

My guage is deff wrong, when I was driving to work this morning most of the drive it was telling me I was @ 16-17AFR.....

Anything else I need to check out hardware wise????

 

[SilverBullet00]

BUMP?

I put my wideband in lambda mode. During WOT it goes down to .75-.77-.88, then pegs the guage @ 3500rpm or so. This did not happen on the dyno, is there any reason why the AF would be different on the dyno VS the street? Besides my crappy wideband that is...

 

[the98stang]

BUMP?

I put my wideband in lambda mode. During WOT it goes down to .75-.77-.88, then pegs the guage @ 3500rpm or so. This did not happen on the dyno, is there any reason why the AF would be different on the dyno VS the street? Besides my crappy wideband that is...

You need to log fuel pump duty cycle, load, MAF ad counts, RPM, etc

 

[SilverBullet00]

Well, I have it logged. It looks like my MAF is not being pegged and my FP duty cycle is at .9999 @ 5200RPMs. I MIGHT have a cobra tank and pumps bought, I am not sure. If I do, I will be very happy.

Does the cobra tank and pumps require any kind of a retune?





ALSO

I am doing the wire mod tomorrow... BUT like an idiot I filled my tank full this morning.. I wasnt thinking... can I hook everything up but the one piece of 10ga wire going to the fuel hat... Will this work?

Next weekend I hope to have my GT pump OR my cobra setup and I will finish the wiring then. I just want to see results ASAP!!

Also, will this relay work?

 

[SilverBullet00]

UPDATE:

So here is what I did today-

I did the wire mod ...everything but running the 10ga wire from the FPDM to the fuel pump (and this was because the tank was FULL). It seemed to help a little bit, but the AFR was still MESSED UP on the wide band.

After a test drive I decided to let the car cool down, and was going to change the wideband sensor. I rerouted the bypass valve and boost gauge vacuum lines to the line coming off the back of the plenum, instead of the line coming on of the FPRS. I did this just to make it look cleaner... Once the car was cool I replace the sensor with a Bosch sensor from a turbo VW, which I read was the same sensor.. It wasnt a direct swap, I had to use zip ties to keep the connector connected, and then wrap the assembly in electrical tape.

After that I looked at my MAF extension wires. I thought they were around 6-8in long.. turns out they were 12-14in long!!! so I trimmed them down to 5in or so and wired them back up. I was hoping the longer wires were causing a delay of some sort.

I was testing one thing at a time and taking if for a test drive to see the results, but I just started to run out of time. I did the wideband sensor and MAF at the same time, and after that under WOT I dont read over .83 lambda, which was what the dyno was showing!!!!!!!! I was so happy!

So, i dont know what fixed it, but I am good to go now. I hope to get the 04 cobra tank and pumps next weekend, hopefully that will make me max out my AFR @ .80 !