Llifter tick and misfire on 4/6/8 only in gear..any ideas?
09-01-2011, 03:21 PM
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Llifter tick and misfire on 4/6/8 only in gear..any ideas? Ok so my 99 TA has developed a lifter tick so i realize gonna have to pull the top end but what else is bothering me is it idles perfect in park yet in gear MAJOR misfire issues on #'s 4/6/8. Plugs and wires are good. Car is stock other than pacesetters and texas speed y pipe and street tune. I know i have to replace the lifters but the misfire issue is bothering me. What would cause this and only on that one side? By the way im using an aeroforce interceptor gauge to track the misfires. Any input would be GREATLY appreciated guys.
09-01-2011, 08:37 PM
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Ok no SES light but has stored code for EGR even though its been deleted but tuner said thats normal. After little more playing it doesnt misfire much if i just put it in gear but if i foot brake it to put a load on the motor holy ****...misfires galore on those 3 cylinders. Seems kinda strange that i develop a lifter tick and then this all at once though.
09-01-2011, 08:56 PM
#5
In the absence of a SES light the most likely source is ignition - wiring harness, coils, wires, and plugs. Since you have the problem on more than one cylinder that suggests wiring harness, including the grounds. I would check the grounds starting with the negative battery strap and the grounds on the back of the cylinder heads.
Although less likely given the multiple cylinder problem you could recheck the plug wires with an ohm meter - they should show between 397 and 1,484 ohms of resistance. With respect to the plugs, if they are gapped too wide with a little age on them they can become misfire prone. GM's gap spec is 0.040 inch.
When a fuel injector goes bad, it can cause problems on the entire bank of injectors, which is consistent with your multi-cylinder symptoms. Although, a faulty injector usually throws a code (eg. lean code) you might check the fuel injectors as has already been suggested.
You can swap injectors, and coils for that matter, from side to side to see if the misfires follow specific parts.
Although less likely given the multiple cylinder problem you could recheck the plug wires with an ohm meter - they should show between 397 and 1,484 ohms of resistance. With respect to the plugs, if they are gapped too wide with a little age on them they can become misfire prone. GM's gap spec is 0.040 inch.
When a fuel injector goes bad, it can cause problems on the entire bank of injectors, which is consistent with your multi-cylinder symptoms. Although, a faulty injector usually throws a code (eg. lean code) you might check the fuel injectors as has already been suggested.
You can swap injectors, and coils for that matter, from side to side to see if the misfires follow specific parts.
