nosebleedZ Posted January 27, 2007 Share Posted January 27, 2007 Garrett, I had a similar problem about two years ago. I think your ignition pulse is erractic. I don't post much here (I like to read mostly), but I've seen this a few times in my ten years of owning, building, & bleeding Z's. If you are running a stock configuration ECU (ECCS or EFI), the ignition fires the mixture on every 3rd injection pulse (ie., half of cylinder fuel-intake stroke (one injection), second half of cylinder fuel -power stroke (two injections), spark ignition & cylinder saturation (cooling during explosion). If the incorrect injection pulse to ignition ratio is upset, for instance fires the mixture too early or too late, then the car will smell flooded from the stray 3rd injection or the beginning of the next injection cycle. Basically, power will suffer either way. It will pull like a banshee and flatten by 4K from cylinder starvation (early) or will be sluggish from idle and hit it's stride @ 4K & pull to redline from the overrich fuel. Unfortunately this is difficult to troubleshoot & it usually ends up being a bad ECU or distributor. But the FSM has a voltmeter test to determine which one. I can probably find it for you. Mine ended up being the ECU. The engine sensors & negative wire from the coil (tachometer signal) triggers injector pulse through the ECU. I hope this helps some. These cars will drive you nuts with analog EFI gremlins! I've been there many, many, times. Link to comment Share on other sites More sharing options...
dr_hunt Posted January 27, 2007 Share Posted January 27, 2007 You know this is the second time the same person has revived years old posts. Seriously, do you have a problem reading, if not, then pick topics that haven't yet been resolved. Link to comment Share on other sites More sharing options...
twoeightythreez Posted January 28, 2007 Share Posted January 28, 2007 [len:Because when I bought the car I had to repair the windshield due to previous owner wiggled while driving and his foot was still on the accelerator slap:] Wow, so this guy not only did the wiggle thing while foot was on gas, but he was in REVERSE too....and his head's really hard... Or am I missing the details of a Z rearending another car? ( Link to comment Share on other sites More sharing options...
nosebleedZ Posted January 28, 2007 Share Posted January 28, 2007 I second Vashon's diagnosis, this happened to me a few years back. It's either ECCS/ ECU fault or distributor. This is an ignition problem, not a fuel problem even though they correlate for injection timing. Stock Z EFI ignites the mixture every third injection in the cylinder. If the ignition signal (input from tach negative signal wire) is erractic, distributor optical plate is bad (dirty), or the coil/ module is bad, it will cause injections to be to early (a whipped pup to 4K & the pull hard past this from an overrich condition) or too late (pull like a banshee till 4K & then hit a wall). Both of these scenarios will cause a bad fuel odor, as well as give suspect plug readings. This is difficult to troubleshoot without a factory shop manual/ disc or ECCS/ EFI analyzer. My problem was a bad input from the MSD box, but I have seen this with the factory ignition module as well. I hope this help! Been here, it sucks. Z electronic gremlins are an acquired taste....LOL! Link to comment Share on other sites More sharing options...
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