Back to the engine not wanting to rev up and the Tech 2 displaying an idle speed of around 5200 RPMs….. I also forgot to mention it was dropping crank sensor codes. To make a short story very long, the code and erroneous RPMs had me instantly suspect sometangwong with the tune given I installed a 24x reluctor wheel for the sake of running an 0411 ECM. So, the next morning I get on the horn with Troy at Howell and he quickly blames the crank sensor as defective, blah blah blah. I gave it a thought and started researching part numbers for a 4x L29 crank sensor vs a medium duty L21 with a 24x reluctor and sure enough they are indeed different part numbers (Connectors too, of course) so an order with placed with Rockauto. All I can do now is wait..
A week goes by and the much more robust L21 crank sensor arrives (mostly brass bodied opposed to plastic style used on the L29). I back probed the terminals out of the L29 crank sensor connector and move them to the L21 style connector…luckily, they were the same pins just a different connector body. Hook up the battery, fire up the Tech 2 and lite it up with the EXACT same issue so I get Troy back on the phone and he starts looking at the tune. I reminded him again for the 832nd time that I am running a distributor on this engine, not coil near plug like a L21 then we had to have a whole long unnecessary conversation about a distributor vs. cam sensor definitions and which do I actually have. Yes, I understand that GM stupidly calls a distributor a “Cam Sensor” in the 96+ L21s, L29s and 4.3s, but they also call the coil near plug L21 oddball looking cam sensor that goes in the dizzy hole a “Cam Sensor” as well. I’m like look dude, it’s a dizzy with a cap, rotor, and wires sticking out of it just like an L29 and just like I told you I planned to run since day one. Actually, he and I began this L29 0411 ECM discussion a few years prior when I did the L29 in the SuperSportside (in the post above) when I regretted running it on a black box ECM due to less than sterling tuning abilities. He said he would research my current issue on his end and call me back the following week meanwhile; I started doing more research on my own, which I should have done from the beginning rather than rely solely on his guidance on this whole 0411 conversation for the past few years.
So, over the weekend I did my research and called him back on Monday morning and asked why we needed a 24x reluctor with an 0411 ECM when the 2002 Chevrolet Express ran an L31 350 with a dizzy and 0411 ECM on a 4x reluctor (a one-year animal). After some silence he pretty much agreed we did not need a 24x reluctor when using a dizzy and said he didn’t realize I planned to use a dizzy. This pissed me off because that has been the genesis of our conversation for a couple years… I WANT TO RUN A DIZZY! This isn’t the first time I’ve had firm conversations with Troy over the past decade or so. He is really a great guy and I totally understand he hops from one freak of nature tune job to the next job and its easy to get his wires crossed (pun intended) nor is it possible to know every single thing.
Now at this point, it starting to look like either scrap the dizzy and start procuring 8 coils, coil harness, oddball L21 crank sensor and chase down a pair of extinct L21 valve covers to mount the coils on or yank off the 24x and go back to a 4x reluctor. I didn’t want any part of going on a L21 parts and pieces scavenger hunt plus coil near plus engines like LS, 8.1s and L21s are flat out ugly with the coils plastered all over the valve covers. The L29 is an awesome looking engine because it is so clean looking even if it does have an archaic dizzy along with long plug wires strung about. I’m also well aware what a pile of crap the 96-02 dizzys are and will definitely be carrying a spare with me. But, I’d be carrying a spare cam sensor with an L21 set up anyway just like I do with the 8.1.
In the end, I wound up pulling the front of the engine off to replace the 24x back to original 4x. I wasn’t very happy about that as I had the engine sealed so nice and once you peel the timing cover back off they never seem to seal quite right to the oil pan again afterword's.
Meanwhile, he burnt a new ECM using the 2002 L31/0411 with L29 calibrations. The next week it fired up and ran pretty decent and even revved up. The Tech 2 even broadcasts the correct RPM now too boot. Then it sat for several weeks while I did other projects and went on work travel and the next time I fired it up to move it out of the garage is when I found it pouring gas out of the exhaust manifolds while shooting flames everywhere! Even the drips of fuel on ground were on fire
. It is losing fuel pressure pretty quickly when the engine is turned off, like it has a leaky injector and I don’t recall replacing them before so it seems like a solid place to start but I won’t rule out an issue with his tune either. My exhaust guy is also my local tuning guy so once it gets a windshield and doors, I’ll tow it to his place so he can run the exhaust and see about the tune. His lift for doing exhaust is outside and why I want a windshield and doors before I take it to him plus I know it will sit there outside for a week or so while he does his thing.
These are the pictures from the day I drove it in and out of the garage into the sunlight when it almost burnt Pueblo County to the ground. I almost forgot to mention that I had our local driveline shop build me a front driveshaft out of 2 others I had laying around so it’s a front digger at the moment. I actually rebuilt the CV myself, which wasn’t too bad. I always farmed out CV rebuilds because I heard they were totally PITA. It went so much easier than expected and saved me a ton of money by doing it myself. I’m going to wait on the rear shaft until after I get the rear suspension settled and the load of the interior buildout all done.
