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I have a rebuilt 1998 Chevy Tahoe with the 5.7 Vortec Vin R (L31) rebuilt into a 383 in a 2 door sport model.
Without the Air intake on and the MAF unplugged everything is good. With it on…I get random misfires.
i see 2.5 amps of AC current on the fuse box battery feed line via my Klein ac/dc clamp meter…which seems odd to me.
Anyone have thoughts? I don’t have a scope yet…so thought I’d ask the experts if I have a noise issue from AC current (that I think is from my Fuel pump)…though pressure is great.
Sounds like a cool truck.
I've never tried measuring AC current on a car. My first thought is I don't trust the amp clamp.
They're pretty cool, and accurate enough most of the time, but...
If you believe there is excessive AC voltage present, I prefer to check for volts AC (or with the scope AC coupled) at the battery terminal on the alternator.
There's some Scanner Danner videos regarding checking for AC ripple, which is caused by failing alternator diodes. Let me see if I can link one in here....
Thank you Noah! I have a cheap scope coming today. Any chance I can convince you to look at my post from a few days ago? It has more details on the mystery. Truck runs fine until the computer and sensors take over…it’s driving me crazy!!!!
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