You won't be able to log fuel pressure, you'll need to hook up a gauge for that.

 

Sorry, didn't see the last two replies until now... Strange no email alert...

Well, I'm hoping to attach a log of my nearly 1 hour ride home, again at 5 second intervals. And yes, no logging of pressure without a gauge.

Of note, at about the 40 to 45 minute mark of my commute (not sure), I lost much power on the freeway, the car would not go above 3200 or so RPM, and would not accelerate fast. Had to get in the far right lane. I suppose this is limp mode, but I don't know...

I dreaded going into the canyon, but I put my flashers on, and soon had a couple of cars behind me, including a Miata that I usually play with. Drat. After coasting down, I pulled-over, turned-off the car, and restarted it and I was able to lay some rubber down. Oh, the EML had come-on, but was off after the restart...

After downloading the info when I got home, I see two codes:

P0172, and a new one for me, P2138, which has to do with throttle/pedal position sensor/switch 'D' / 'E' voltage correlation...

Looks like I can't attach Excel Word it is...

 

You may want to check out the Helix site. You sell OEM Bosche Injectors with the stock dual cone spray pattern that are MUCH more reasonable. I think they're around 240...

 

Thanks Nick. Just checked Helix, and they are 260 bucks. For 35 more, they sell JCW's... I think I saw JCW's for 225 somewhere... I'd like to make sure this is the problem though before I part with a 200+ dollars... I'm going to unplug my UNIChip for a while and see what that elicits... Thank you.

 

.

 

It is definitely trying to lean out your mixture.

 

I'll take your word on that, as I can only guess how you deciphered that...

Tonight I decided to clear the code, and disco the UNIChip. I went for about a 20 minute drive, and came back code free. I will do another hour or so, and if the code does not return, then the UNChip tune is most likely the culprit.

I am logging also, so I will pull that data at a later time, if need be. Thanks for your input!

 

and you're not running an ECU flash, then you will shift the "untrimmed" operation point to the rich side. it's just a guess how far you can go without codes being thrown. But the window for operation is surely narrowed.

I'd throw the stockers on, and not use the UniChip, untill you really go for an optimal tune.

Matt

 

The stock injectors were "traded-in" a good 3+ months after the 400 install. Again, I had no such code until well after the install of these injectors. This surfaced shortly after my ceramic-coated header install... which is also when I twisted the O2 sensor wires more than they should have been... I'm not saying it's not the injectors, but just odd as to why I didn't see this code much sooner; unless an injector went bad...

The UNIChip has an A and B "map" which is to be used with race gas. I had always had it on the B map as I was told to do so if it didn't throw a code...

Any idea if the A or B map option would be a factor here in this too rich code?

 

Every case i've seen with this code has been with 400+ CC injectors and lightly modded cars (IE No headwork, or only moderate headwork). I'd swap those injectors out, but that's just me.

FWIW I spoke to Helix recently and the JCW Injectors went up in price by a LOT (150-200) they're pretty much comparable in price to Outmotoring, etc. The Bosche Injectors are just as good, with the OEM dual cone spray pattern rather than redrilled stockers

 

If you'd been running larger injectors, is it possible you "aged" the O2 sensors quicker? They don't like running rich at all. They degrade gradually over time. Rich greatly accelerates that. Maybe you reached a threshold with them? They might not be throwing a code themselves, but might be off enough that it shifted things so that where you're operating on the map shifted or something?

If it were me, I'd swap the injectors and also the O2 sensors.

 

changes flow through the head and all that other stuff. Remember, all this stuff interacts. But Tony, you're getting farther and farther from stock. Expect this if you don't get a tune. I live with a recurring lean code on freeway driving, the Stahl and a custom tune are what I hope makes that all go away.

I guess we're just lucky.

Matt