Rough idle and misfire
tahoedriver
01-12-2018, 08:32 PM
Got a 97 Tahoe with 280k miles on it and its running and idling rough. I've changed the plugs, cap, and rotor two days ago. My suspicions are a dirty MAF and/or ignition coil (which is stock). Any suggestions or thoughts would be appreciated. Thanks.
Tech II
01-12-2018, 09:01 PM
Well, when you replaced your plugs, did they all look the same, or were some more fouled than others? Did you change the plug wires too? Use OEM plugs?
Well, I would put a spark tester on the end of each wire, one at a time, just make sure you have a healthy spark to each plug.....
Other possibilities are compression problems in a cylinder(s), bad bearing in the distributor, bad injector, vac leak, etc.
Have you scanned for codes?
Well, I would put a spark tester on the end of each wire, one at a time, just make sure you have a healthy spark to each plug.....
Other possibilities are compression problems in a cylinder(s), bad bearing in the distributor, bad injector, vac leak, etc.
Have you scanned for codes?
j cAT
01-14-2018, 07:49 AM
[quote=tahoedriver;7207158]Got a 97 Tahoe with 280k miles on it and its running and idling rough. I've changed the plugs, cap, and rotor two days ago. My suspicions are a dirty MAF and/or ignition coil (which is stock). Any suggestions or thoughts would be appreciated. Thanks.[quote]
ZZZZZZZZZZZZ
maf does not cause rough idle . causes a delayed power of engine. fuel pressures should be checked. distributor rotor will wobble on these if over 175K miles. if plugs looked good a light color then compression should be good .. the injectors are a problem on these at this age also rough idle . pcv and all the vacuum lines should be replaced with any defects ..
ZZZZZZZZZZZZ
maf does not cause rough idle . causes a delayed power of engine. fuel pressures should be checked. distributor rotor will wobble on these if over 175K miles. if plugs looked good a light color then compression should be good .. the injectors are a problem on these at this age also rough idle . pcv and all the vacuum lines should be replaced with any defects ..
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