D15, D16, D17 and Mini-Me swaps
By BrentVX92
#323118 So, I'll try my best to describe what's going on with my d15z1.
Simply put, the car will start and run fine till operating temp. is reached. At this point i get a terrible miss that i believe is caused by a fuel issue. It seems to drop off a cylinder(s) then its hardly drivable. No CEL. Barely idles when at operating temp. javascript:emoticon(':x') i read similar topics on here just not one covering my specific issues.

Items recently replaced: plugs, wires, dizzy, fuel filter.
Planning on replacing the injectors this weekend with used units. What are some other cars that would have the same ones or ones that will work? ive read that OBDI injectors with work with whatever? Any help will be apprieciated.
Thanks,
Brent from TN In a Camo EG
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By teal_dx
#323146 If it were the injectors, the idle problem would happen all the time I would think...

If the problem is happening when the engine is warm, that makes me wonder if it is something coolant related. I'd check out the FITV, IACV. Often they get gunked up from old coolant and need to be cleaned out after a while.
By BrentVX92
#323179 After driving my 45 mile round trip to work and back today i have determined that lean burn isn't engaging at all. i can keep the throttle in its "sweet spot" and drive the car kinda like normal, but when there is a load applied(say going up a hill) the miss happens. If I back out of the throttle and maybe change to 4th, i can keep the throttle in the sweet spot. In town its way worse because of the load factor at low speeds. again i have to stay in the sweet spot at lower rpms. it still sputters when in Neutral.

What is the FITV? idle air control is the other acronym if im not mistaken.
Thank you teal_dx for your hypothesis!

Im headed to a mechanic friend of mine and he's going to drive it and see what he thinks.[/b]
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By suspendedHatch
#323203 The VX is very prone to major symptoms from minor issues. I had a minor vacuum leak on mine and it caused serious bucking.

When your car is warming up, it's running in open loop - ignoring all sensors and using look-up tables to determine fueling, ignition etc. Once it's at OT it switches to closed loop. You need to TEST your sensors. I suggest starting with the O2 sensor.
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By FlopUrDonk
#350187 is the IACV located in the same spot as a fitv? Also. Will cleaning and re tightening solve my idle surge as bleeding the radiator didn't? I know this is a repeated question but I've read the d15z1 has an IACV and not a FITV. Just wanted to know before I Dive in to solve the prob. :? Or is there a diy for the d15z1 anywhere?

New to d series :)
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By brandoff88
#350189 they should both be on the throttle body or abouts there, and surging idle could be coolant needs to be bleed of air, iacv, or fitv id check each one and clean then readjust as necessary like teal said, lots of good stuff on the forum and interwebs, just google your questions, search for a few min and then get a second opinion.