some testing results, still problematic
Well, over the weekend I did several experiments with the new CAI. Trying to figure out what the heck is going on. The MAF is clean with no clogging on the resistor/sensors. The ACT (Air Charge Temperature sensor???) I don’t believe I have one do I?? The IAT (Intake Air Temperature sensor has been deleted via a set resistor long ago. There are no vacuum leaks and other than a larger diameter intake tube, all is/was the same as before with the old CAI. Here are the results of my tinkering
1) I reinstalled my crappy homemade CAI and the car runs just as it did. Smooth idle, no hesitation off the line under all pedal positions, no power loss or bogging at all rpm ranges and normal transmission final gear lock up is good. MAF sensor is plugged in.
2) I put the new CAI back on, car idles smooth, no hesitation off the line and smooth acceleration under all pedal positions BUT… At any speed and in any gear WOT above 2500rpm causes bogs and surges. If I had to describe it, it’s almost as if I was pulling my boat, the engine is trying but seems to be starving of gas and surges as if sometimes it gets enough fuel. The trans shifts into final lockup and the MAF is plugged in.
3) With the new CAI on and the MAF unplugged I get a little hesitation off the line unless I floor it and keep floored or floor it real quick and back off to any other accelerator position. Idle is smooth and acceleration is great in all gears or rpm ranges, in fact pretty damn good. The trans will not shift into final lockup with MAF unplugged.
4) With the new CAI installed, MAF plugged in and duct tape around 75% of the outer portion of the filter, all is well with no hesitation, excellent acceleration at all positions and at all rpm ranges. Trans shifts normally into final lockup.
Now for the heavy load test—Da Boat
Scenario 1, 3, 4) With my boat hooked up, (1,470 pounds loaded) all results were the same as above with the exception of obvious loss of power due to the tow load.
Scenario 2) I have almost zero power at WOT and I mean almost zero, all other pedal positions are ok, but not WOT.
Conclusion as far as I can tell—Since the CAI isn’t forced or ram air and the engine will only “suck in” as much as it can take in, there is a fuel shortage with the MAF connected using the new CAI. Now here’s the kicker. How do I get more fuel in there? Can I trick the computer, or are we looking at bigger injectors, new higher flow MAF, stronger fuel pump? I’ve read on other threads about swapping a Cobra MAF and injectors for the turbo upgrade but those weren’t for the DIS dual plug engines like mine and may be too much for a N/A engine and will they even work on the DP DIS???
I could live with the MAF being disconnected and do the quick floor it from a stop to prevent the slight bogging, but I’d like the trans to lockup.
This really has me stumped and I’m sure there are geniuses out there that can help.
Here’s my engine stats for more info.
2.3 DIS Dual Plug EEC-IV
Custom header with full flow exhaust (not dual yet)
Thrush Turbo muffler
Accel supercoils
Capped off EGR
IAT resistor
CAI
I usually use mid grade 89 octane and Shell gas only.
Thanks you in advance for your help guys-Jeff
287K and rising