Have a '91 4.3 L that backfires after it is started, have installed new plugs, coil, rotor/cap, wires, this is a reman engine with 20,000 miles on it, lifters are ticking real bad on rt. front, I think from the backfiring. whats is going on??
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1991 Chevrolet S10 Question: 1991 S-10 4.3 L 4x4 pu
Answer #1Superbob May 30, 2011, 14:47Master
Because of the lifter noise, I think that you have valve problems which are causing the backfiring. If the camshaft lobes are damaged or the intake valves are not closing properly it could cause backfiring. Check compression and with the valve covers off, check to see that the valves are moving properly.
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Replyjstar, May 31, 2011, 01:49Rookie
The compression is good on that side, at least that's what the last mechanic stated. I think the valve problem came from the backfireing and the machanics (ones I've been to) haven't found the problem yet.
Answer #2Visitor, June 22, 2011, 18:15
probably wiped the lobe off the cam