Here's a video for you Dave. Shows Automatic trans behavior.
Location: FL
Posts: 948
My VIN: Early
Here's a video for you Dave. Shows Automatic trans behavior.
Early 81 5spd conversion- DMCH Ground Effects, Double Din, Custom Instrument Cluster, QA1 Suspension, 3.0 PRV with MS3
Location: Leonardtown, MD
Posts: 9,006
My VIN: 03572
Thanks. Right now my ECU software does not do anything above 1300 RPM (it just holds the idle motor at normal idle RPM position). All my work is when it drops below 1300 RPM. The software has to not drop that idle motor setting until it gets to normal idle RPM. What I found works good was try to hold 1100 RPM which was working good until my Kjet was doing random things.Originally Posted by 81dmc
Location: Leonardtown, MD
Posts: 9,006
My VIN: 03572
Well I tested with all 6 injectors in jars and the fuel pump running and all looks good. With no air plate pushed I just get a few drops from each injector. Pressing the air plate all injectors spray nicely. I even put the CSV in a jar and powered it and it sprays great.
So now I'm going to start checking ignition. I see the tach bounce 0 to 500 RPM when cranking but not sure if that is normal because my engine always starts fast. From past experience I would see a more consistent 700 RPM when cranking.
Location: Northern NJ
Posts: 8,581
My VIN: 10757 1st place Concourse 1998
From this experience you can see that you must engineer this so that it will work in spite of the condition of the motor and it's systems. What I mean is many of the cars I see do not run perfectly. Between vacuum leaks, bad spray patterns, etc, they do not idle well. No amount of software is going to compensate for the mechanical defects that usually exist in the fleet. Some will buy your device hoping it can compensate or correct for all of the other problems they have and will be disappointed when it doesn't and can't.
David Teitelbaum
Location: Leonardtown, MD
Posts: 9,006
My VIN: 03572
Well it's getting spark. I put the timing light on a couple plug wires and it fires when cranking. I can't think of what could cause it to never fire. I tried some starter fluid and still not even the hint of a fire. I'm wondering if an intake valve is stuck open. I guess I could put a vacuum gauge on the intake and see if it pulls any vacuum. I've never tried checking vacuum when cranking.
Location: FL
Posts: 948
My VIN: Early
Try ether.
You won't get a lot of vacuum when cranking. The only way to check valve sealing is differential compression. Though if it was a stuck valve, it would fire on other cylinders.
Early 81 5spd conversion- DMCH Ground Effects, Double Din, Custom Instrument Cluster, QA1 Suspension, 3.0 PRV with MS3
Location: North GA
Posts: 6,177
Club(s): (SEDOC) (DCUK)
I agree, a stuck valve would probably make it back fire on its cylinder and the rest should still hit.
(Still sounds like fuel fouled plugs... ;-)
Location: Leonardtown, MD
Posts: 9,006
My VIN: 03572
I was thinking an intake valve stuck open would not let it pull any vacuum (fuel and air). Well I checked vacuum and it just makes the gauge oscillate between 0 and 1 inch when cranking.
Spark and fuel should fire if it pull into the cylinder. I need to get a compression gauge. That would show any bad cylinder.
Location: FL
Posts: 948
My VIN: Early
I recommend OTC 5609
https://www.amazon.com/dp/B0030EVL60
It has PSI on both sides. I use that on aircraft.
If a valve is leaking bad, pulling valve cover and hitting it with a hammer under pressure will likely unstick it.
Anyways, I highly doubt that?s your issue.
Early 81 5spd conversion- DMCH Ground Effects, Double Din, Custom Instrument Cluster, QA1 Suspension, 3.0 PRV with MS3
Location: Leonardtown, MD
Posts: 9,006
My VIN: 03572
Thanks. Yes, why would something act up so suddenly. But I'm open to any other suggestions. Google says 3 to 5 inches during cranking but is that for K-jet.
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