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I went out to the garage, not wanting to give up, and removed spark plug one. I got the piston #1 to TDC... I did it extremely slowly, and sure enough the harmonic balancer indicator was dead on 0.
I immediately oriented the distributor, marked where spark plug 1 (post) would be, and then hassled for like 10 minutes to get the rotor to point directly on it and got it perfectly lined up.
Hooked everything back up, and guess what... there is absolutely NO fuel coming out of the injectors. In the videos above, you can kind of see the injectors pulsing, like... stopping and starting. I don't know what's going on, but I'm making the assumption that either my fuel pump is clogged, or the fuel filter is... both of which I've already changed. I do hear the click and I hear something humming for 5 seconds just as I turn the key.
Ok... just went back outside again and tested a couple of things. I turned the key and quickly went around and put a 9v on the injector (tested both of them) and I get a SUBSTANTIAL spray.
So, I have a noid light, so I just hooked that up to the injector cable, and I get NOTHING when cranking... nothing at all. ECM still says the same two codes, 34 and 42.
I'm thinking my ECM may be bad? Thoughts?
Ok, I am a tard. I really am... I've been working on this thing all day and I'm exhausted. I went back outside because it occurred to me that I may not have plugged back in the distributor coil and power harness. Yup... nothing was plugged into it, so the ECM wasn't getting a reference. I plugged it back in, and the car started right up. Here's the problem... it now starts immediately, plenty of fuel, lots of spark, runs very smooth... but it dies after about 8 seconds of running. It tries to keep it going, but it just doesn't do it... it chokes out. I start it again, and does the same thing... runs for about 6-8, and then dies.
You need to look at live data. Look at the coolant temp sensor at start up. Might be showing -40f. Like I said earlier those early coolant temp sensor were a bad design. When I did my first intake swap I unplugged it and it would never run right, even with a new (old) style sensor. Chevy released a TSB on that problem too.
I went out to the garage, not wanting to give up, and removed spark plug one. I got the piston #1 to TDC... I did it extremely slowly, and sure enough the harmonic balancer indicator was dead on 0.
I immediately oriented the distributor, marked where spark plug 1 (post) would be, and then hassled for like 10 minutes to get the rotor to point directly on it and got it perfectly lined up.
Hooked everything back up, and guess what... there is absolutely NO fuel coming out of the injectors. In the videos above, you can kind of see the injectors pulsing, like... stopping and starting. I don't know what's going on, but I'm making the assumption that either my fuel pump is clogged, or the fuel filter is... both of which I've already changed. I do hear the click and I hear something humming for 5 seconds just as I turn the key.
Ok... just went back outside again and tested a couple of things. I turned the key and quickly went around and put a 9v on the injector (tested both of them) and I get a SUBSTANTIAL spray.
So, I have a noid light, so I just hooked that up to the injector cable, and I get NOTHING when cranking... nothing at all. ECM still says the same two codes, 34 and 42.
I'm thinking my ECM may be bad? Thoughts?
Ok, I am a tard. I really am... I've been working on this thing all day and I'm exhausted. I went back outside because it occurred to me that I may not have plugged back in the distributor coil and power harness. Yup... nothing was plugged into it, so the ECM wasn't getting a reference. I plugged it back in, and the car started right up. Here's the problem... it now starts immediately, plenty of fuel, lots of spark, runs very smooth... but it dies after about 8 seconds of running. It tries to keep it going, but it just doesn't do it... it chokes out. I start it again, and does the same thing... runs for about 6-8, and then dies.
Kind of at a loss at this point.
is car running off of the initial fuel pressure only.
+1 on the coolant temperature sensor. On my car, you can actually hear the injectors clicking at idle, and you can easily see the distinct spray cones with your own eyes. Judging by your video, your injectors are just straight-up dumping fuel. The ECM probably thinks it's -40°F outside. Definitely double-check the temperature sensor and its connector.
Conversion kits, no affiliation!👍 Older style, notice plug connector style. This would be my preferred choice because the connector type is more period correct AND I'd rather have a sensor produced in the past than today!!! New kit, again, notice the modern connector of the pigtail...it's cheaper, but will also have shipping costs.
Last edited by '78CorvetteS.A.; Yesterday at 05:28 AM.
You need to look at live data. Look at the coolant temp sensor at start up. Might be showing -40f. Like I said earlier those early coolant temp sensor were a bad design. When I did my first intake swap I unplugged it and it would never run right, even with a new (old) style sensor. Chevy released a TSB on that problem too.
Do you happen to have the TSB? I would love to read that just to see what it says. I'll buy a replacement sensor... might as well. It comes with a separate ground anyway... just not thrilled about this.
Originally Posted by mike1111
is car running off of the initial fuel pressure only.
I don't know... I don't think so. The one thing that concerns me is that I cannot get the fuel pump to run by providing power to the lead on the ALDL connector. I don't know why that is... it's possible the wiring was messed with, but I'm just not sure.
Originally Posted by Volodaka
+1 on the coolant temperature sensor. On my car, you can actually hear the injectors clicking at idle, and you can easily see the distinct spray cones with your own eyes. Judging by your video, your injectors are just straight-up dumping fuel. The ECM probably thinks it's -40°F outside. Definitely double-check the temperature sensor and its connector.
Ok, I'll check.
Originally Posted by '78CorvetteS.A.
Conversion kits, no affiliation!👍
Older style, notice plug connector style. This would be my preferred choice because the connector type is more period correct AND I'd rather have a sensor produced in the past than today!!!
New kit, again, notice the modern connector of the pigtail...it's cheaper, but will also have shipping costs.
I had a similar problem with my daughter's 85 Fiero 2m4. It actually uses the newer CTS sensor (that you're telling me to install here). We had to go through like 3 different sensors before we found one that actually measured the correct temperature... they were all saying it was insanely cold outside, even when it was like 80 degrees outside. I think it's part of why GM went to an IAT sensor.
I can swap this out easy... I might as well buy a new one. I know the extra lead is ground, just hope this is really the problem. Thanks!
Ok, I just ordered one from NTK that comes with the new harness. I suppose regardless, it now has a dedicated ground, so I don't have to worry about false readings from pipe sealer.
I'm not convinced this is my problem though as I am not getting that error it says in the TSB. But I'll try anything at this point.
Also... my flywheel has some teeth missing, and I can hear it as it's spinning and grinding in one place. Looks like I'll have to drop the transmission at some point to put in a new flywheel. Hopefully removing the transmission isn't too much of a pain in the *** on this thing. Not a big deal, but definitely something I'll need to do long term.
Designer Imagines A Corvette That Looks More Like a Corvette Than the Corvette
Slideshow: A Jaguar designer's personal project imagines what a modern front-engined Corvette might look like if Chevrolet revisited the golden age of the Stingray.
